DECODING

EVAPORATIVE
AIR COOLERS
INSTITUTIONAL
FRAMEWORK

TECHNOLOGY

POLICY

STANDARD

ENERGY
RATING

GAP AND
RECOMMENDATION
REGULATORY
FRAMEWORK
THERMAL
COMFORT

MARKET

Ms Srishti Sharma, Mr Akhil Singhal and Mr Tarun Garg June 2021

Project: Alliance for Sustainable Habitat, Energy Efficiency and Thermal Comfort (SHEETAL)
“The Alliance for Sustainable Habitat, Energy Efficiency and Thermal Comfort (SHEETAL) is a consortium
of Civil society organizations led by The Energy and Resource Institute (TERI) with the Alliance for an
Energy Efficient Economy (AEEE), and the Council on Energy, Environment and Water (CEEW) as partners.
Supported by CIFF, SHEETAL facilitates the roll out of India's sustainable cooling agenda enshrined in
the India Cooling Action Plan. Engaging with national and international stakeholders, the consortium
partners discuss, identify and test integrated approaches best suited to improve the development,
access and use of energy efficient cooling practices and technologies for R&D, space cooling, cold
chain, transport air-conditioning, and the servicing sector. SHEETAL convene different line ministries and
international and domestic cooling policy experts to collaborate and synergise actions to accelerate
sustainable cooling in India”.

Funded by: Children's Investment Fund Foundation (CIFF)

CIFF is a philanthropy organisation working towards the upliftment of children’s quality of life, in
developing countries. There areas of work are inclusive of maternal and child health, adolescent sexual
health, nutrition, education, and deworming, tackling child slavery and exploitation, and supporting smart
ways to slow down and stop climate change. Their prime focus towards quality data and evidence-
based approach to measure the impact.

Prepared by: Alliance for an Energy Efficient Economy (AEEE)

AEEE is a policy advocacy and energy efficiency market enabler with a not-for-profit motive. AEEE
advocates energy efficiency as a resource and collaborates with industry and government to transform
the market for energy-efficient products and services, thereby contributing towards meeting India’s goals
on energy security, clean energy and climate change. AEEE collaborates with diverse stakeholders
such as policymakers, government officials, business and industry, consumers, researchers, and civil
society organisations. We believe that our work speaks for itself and we hold Respect, Integrity and
Synergy as central to our efforts.

Project Team:
Srishti Sharma, AEEE
Akhil Singhal, AEEE
Tarun Garg, AEEE

Peer Reviewers:
National and international experts provided inputs and reviewed preliminary drafts of this report.
Their comments and suggestions were of great value. Therefore, AEEE wants to extend thanks and
acknowledge the following mentioned peer reviewers for providing their valuable contribution to the
report:
Brian Holuj United for Efficiency (U4E)
Nishant Gupta Indian Society of Heating, Refrigerating and Air Conditioning Engineers (ISHRAE)
Ian Butler Eurovent Certita Certification
Prabhat Goel Eurovent Certita Certification
Vanshaj Kaul Eurovent Certita Certification

2 // Decoding Evaporative Air Coolers

Acknowledgement:
Alliance for an Energy Efficient Economy (AEEE) would like to take this opportunity to express its sincere
gratitude to CIFF for providing the grant with which this study was made possible. AEEE extends its
special thanks to all the appliance manufacturers who actively participated in this study and focused
group discussion by sharing their valuable inputs and insights. The interactions with these stakeholders
have immensely contributed to setting the direction of this study and shaping its key recommendations.
AEEE also wants to acknowledge the work driven by the internal core project team, including Tarun
Garg, Akhil Singhal and Srishti Sharma, and the constant guidance and support received from Dr Satish
Kumar, Sandeep Kachhawa and Deepak Tewari.
Many sectoral experts and organisations have directly or indirectly supported the AEEE team in
developing this report. Therefore, AEEE would also like to extend its gratitude and appreciate their
valuable contributions. This report would not have been possible without the support provided
by Dr Prasanna Dontula and Rishabh Matta from A.T.E. Enterprises Pvt. Ltd., Paul Kellet and
Brian Holuj from United for Efficiency (U4E), Prabhat Goel, Ian Butler, Vanshaj Kaul from Eurovent
Certita Certification (ECC), and Nishant Gupta from Indian Society of Heating, Refrigerating and Air
Conditioning Engineers (ISHRAE).

Suggested citation:
Sharma, S., Singhal, A. and Garg, T., 2021. Decoding Evaporative Air Coolers, New Delhi: Alliance for
an Energy Efficient Economy.

Disclaimer:
The views/analyses expressed in this report/document do not necessarily reflect the views of CIFF.
This report is based on a detailed review of the information available in the public domain. Every
attempt has been made to ensure the correctness of data. AEEE and CIFF do not guarantee the
accuracy of any data included in this publication, nor do they accept any responsibility for the
consequences of its use.

Copyright:
© 2021 Alliance for an Energy Efficient Economy (AEEE)

Contact Us:
Srishti Sharma and Akhil Singhal,
Buildings and Communities,
Alliance for an Energy Efficient Economy (AEEE)
37 Link Road, Ground Floor, Lajpat Nagar III, New Delhi 110024
info@aeee.in

Decoding Evaporative Air Coolers // 3

 >+<?

4 // Decoding Evaporative Air Coolers

1

Foreword // 5
Contents List of Abbreviations
and Acronyms

Key Definitions
10

12

Executive Summary 14

1.
Introduction 17
1.1 Background 18
1.2 Objective 21

2.
Understanding 23
Evaporative Air Coolers:
Technology & Market
Assessment
2.1 E vaporative Air Coolers vs. 24
Conventional Air Conditioners
2.2 Evaporative Air Coolers 25
2.2.1 Direct Evaporative Air Coolers 26
2.2.2 Indirect Evaporative Air Coolers 30
2.2.3 Indirect-Direct Evaporative Air 33
Coolers
2.3 Comparison of Evaporative Air Cooling 36
Technologies
2.4 Evaporative Air Cooler Market in India 37
3. 4.
Overview of National 39 Overview of International 55
Institutional, Policy, Institutional, Policy, and
and Regulatory Regulatory Framework on
Framework Evaporative Air Coolers
3.1 I nstitutional Framework for 40 4.1 C
 ountry-Wise Evaporative Air Cooler 56
Appliances Standards
3.2 Policy and Regulatory Framework 43 4.1.1 Australia 56
Governing Evaporative Air Cooler 4.1.2 USA (California) 58
and Appliance Energy Efficiency in 4.1.3 Iran 59
India 4.2 International Testing Standards 61
3.2.1 Indian Standards for 43 4.2.1 ASHRAE Standard 133-2015: DEC 61
Evaporative Air Coolers Testing Method
3.2.2 A  ppliance Energy Efficiency 46 4.2.2 ASHRAE Standard 143-2015: IEC 63
Programmes in India Testing Method
3.3 Gaps and Recommendations for the 52 4.3 I nternational Initiatives 64
National Institutional, Policy, and 4.3.1 Eurovent Certita Certification’s 64
Regulatory Framework Related to Rating Standard for Evaporative
Evaporative Air Cooler Performance Air Coolers

5.
Conclusion & 69 Annexures and 75
Recommendations Bibliography
5.1 National Level Gaps 70 Annexure 1 75
5.1.1 Policy & Regulatory Related 70 Annexure 2 76
5.1.2 Research & Design Related 70 Annexure 3 79
5.2 Recommendations 70 Annexure 4 82
5.2.1 Policy & Regulatory Related 70 Bibliography 83
5.2.2 Research & Design Related 73
Other Possible Interventions 73
Way Forward 74
List of Figures
Figure 1: Global Comparison of Person Cooling Degree Days 19
Figure 2: Climate Zones in India Where Evaporative Air Coolers Work Effectively 20
Figure 3: Types of Evaporative Air Coolers 25
Figure 4: Basic Structure of a DEC 26
Figure 5: Sensible and Latent Heat in Evaporative Air Cooling Process 27
Figure 6: Working of a DEC 27
Figure 7: Psychrometric Chart of a DEC 28
Figure 8: Types of a DEC 29
Figure 9: Applications of a DEC 30
Figure 10: Schematic of an IEC 30
Figure 11: Working of an IEC 31
Figure 12: Psychrometric Chart of an IEC 31
Figure 13: Types of an IEC 32
Figure 14: Applications of an IEC 33
Figure 15: Schematic of an IDEC 33
Figure 16: Psychrometric Chart of an IDEC 34
Figure 17: Applications of an IDEC 35
Figure 18: Indian Institutional Framework for Improving Appliance Energy Efficiency 40
Figure 19: Evolution of the Indian Standard for Evaporative Air Cooler 43
Figure 20: Star Label for Air Conditioners: Comparative Label 47
Figure 21: BEE Endorsement Label 47
Figure 22: S&L Registration Process 49
Figure 23: Typical Cycle for an Appliance Under BEE's S&L Program 50
Figure 24: Institutional Framework for Appliance Efficiency in California 58
Figure 25: Institutional Framework for Appliance Efficiency in Iran 59
Figure 26: Iranian Energy Label 59
Figure 27: Energy Efficiency Thresholds for Iranian Energy Label 60
Figure 28: Key Parameters Under ASHRAE Standard 133-2015 for DECs 61
Figure 29: Key Parameters Under ASHRAE Standard 143-2015 for IEC 63
Figure 30: Acceptance Criteria for DEC Rating 65
Figure 31: Standard RS/9/C/005-2018: IEC Case A 65
Figure 32: Standard RS/9/C/005-2018: IEC Case B 65
Figure 33: Acceptance Criteria for IEC Rating 66
Figure 34: Key Parameters for Evaporative Air Cooler MEPS & Labelling In India 72
Figure 35: A measurement device for air flow: psychrometer with sample tree 76
Figure 36: Component IEC 79
Figure 37: Semi Packaged Secondary IEC with integrated 79
Figure 38: Semipackaged Secondary IEC with nonintegrated 79
Figure 39: Primary IEC 79
Figure 40: Packaged IEC 80

8 // Decoding Evaporative Air Coolers

List of Tables
Table 1: Comparison of Evaporative Air Cooling Technologies 36
Table 2: Role of Organisations in Indian Institutional Framework for Improving Appliance Energy Efficiency 40
Table 3: Key Specifications under IS 3315:2019 for Evaporative Air Coolers 44
Table 4: Water Tank Capacity Based on Minimum Air Capacity 44
Table 5: Power Consumption of Evaporative Air Coolers Based on Air Capacity 45
Table 6: BEE S&L Programme: Mandatory & Voluntary Appliances 48
Table 7: Gaps and Recommendations for the National Policy, Regulatory, and Institutional Framework
Related to Evaporative Air Coolers 52
Table 8: Global Institutional, Policy and Regulatory & Framework for Evaporative Air Coolers 56
Table 9: Rating Temperatures (°C) of the Select Countries 60
Table 10: The Acceptable Temperature and Humidity Test Conditions under ASHRAE Standard 133-2015 62
Table 11: Comparative Summary of Evaporative Air Cooler Performance Parameters* 66
Table 12: Comparison Between Axial and Centrifugal Fans 82

List of Tables // 9
List of Abbreviations and Acronyms
°C: Degree Celsius
ASHRAE: American Society of Heating, Refrigerating and Air-Conditioning Engineers
BEE: Bureau of Energy Efficiency
BIS: Bureau of Indian Standards
BLDC: Brushless Direct Current
BLY: Bachat Lamp Yojana
CAGR: Compound Annual Growth Rate
CEAMA: Consumer Electronics and Appliances Manufacturers Association
CFL: Compact Fluorescent Lamp
CFM: Cubic Feet Per Minute
CNRA: California Natural Resources Agency
CPRI: Central Power Research Institute
CSO: Civil Society Organisation
dBA: A-weighted decibels
DEC: Direct Evaporative Air Cooler
DG: Diesel Generator
DMITRE: Department of Manufacturing, Innovation, Trade, Resources and Energy
E3 Programme: Equipment Energy Efficiency Programme
EC Act: Energy Conservation Act
ECC: Eurovent Certita Certification
ECE: Evaporative Cooling Equipment
ECER: Evaporative Cooler Efficiency Ratio
EEFP: Energy Efficiency Financing Platform
EER: Energy Efficiency Ratio
EESL: Energy Efficiency Services Limited
FEEED: Framework for Energy Efficient Economic Development
GDP: Gross Domestic Product
GEMS: Greenhouse and Energy Minimum Standards
GHG: Greenhouse Gas
GWP: Global Warming Potential
HCFCs: Hydrochlorofluorocarbons
HE: Heat Exchanger
HPMP: Hydrochlorofluorocarbons Phase out Management Plan
HVAC: Heating, Ventilation, and Air Conditioning
Hz: Hertz
IAQ: Indoor Air Quality
IAME: Independent Agency for Monitoring and Evaluation
IBEF: India Brand Equity Foundation
ICAP: India Cooling Action Plan
IDEC: Indirect-Direct Evaporative Air Cooler
INR: Indian Rupee
IS: Indian Standard
ISEER: Indian Seasonal Energy Efficiency Ratio
ISHRAE: Indian Society of Heating, Refrigerating and Air Conditioning Engineers
ISIRI: Institute of Standards and Industrial Research of Iran

10 // Decoding Evaporative Air Coolers

ISO: International Organisation for Standardisation
Kg: kilogramme
kWh: kilowatt-hour
L: litre
LED: Light Emitting Diode
LPG: Liquefied Petroleum Gas
m3: cubic metre
MeitY: Ministry of Electronics & Information Technology
MEPS: Minimum Energy Performance Standard
MFD: Multi-Function Device
mm: millimetre
MoCI: Ministry of Commerce & Industry
MoP: Ministry of Power
MoU: Memorandum of Understanding
MTEE: Market Transformation for Energy Efficiency
MW: Megawatt
NAPCC: National Action Plan on Climate Change
NDC: Nationally Determined Contribution
NIST: National Institute of Standards and Technology
NMEEE: National Mission for Enhanced Energy Efficiency
OEM: Original Equipment Manufacturer
Pa: Pascal
PAT: Perform, Achieve and Trade
PRGFEE: Partial Risk Guarantee Fund for Energy Efficiency
R&D: Research & Development
RH: Relative Humidity
S&L: Standards and Labelling
SATBA: Renewable Energy and Energy Efficiency Organisation
SDAs: State Designated Agencies
SEC: Specific Energy Consumption
SEEP: Super Efficient Equipment Programme
SEER: Seasonal Energy Efficiency Ratio
SERCs: State Electricity Regulatory Commission
SHEETAL: Alliance for Sustainable Habitat, Energy Efficiency and Thermal Comfort for all
SoP: Standard Operating Procedure
SSI: Small Scale Industries
TSC: Total Salt Content
TDS: Total Dissolved Salts
UJALA: Unnat Jyoti by Affordable LEDs for All
VCFEE: Venture Capital Fund for Energy Efficiency
VRF: Variable Refrigerant Flow
W: Watt
WELS: Water Efficiency Labelling and Standards

List of Abbreviations and Acronyms // 11

Key Definitions
1. Psychrometry: The science of understanding air mixture, specifically the dry air, humidity and temperature. It explicitly
deals with the properties of moist air. The psychometric chart is a visualisation tool extensively used in buildings system
design and operations to understand the relation between the physical properties of moist air.1,2,3&4

2. Dry-Bulb Temperature: The temperature of the ambient air (sensible heat). It can be measured with an ordinary
thermometer. The unit is degree Celsius.5

3. Wet-Bulb Temperature: The lowest temperature that can be achieved through evaporation at 100% saturation
effectiveness. After reaching this temperature, air cannot be further cooled through direct evaporative air cooling. The wet-
bulb temperature determines the amount of humidity present in the air. If the humidity is more, the difference between the
wet-bulb temperature & dry-bulb temperature will be less; this denotes that not much evaporation is possible. Generally,
the unit is degree Celsius (°C) or Kelvin.6

4. Enthalpy (kJ/kg): The sum of both sensible and latent heat and measures the total heat content in the air.7

5. Relative Humidity (%): The ratio of the actual mass of water vapour in a given volume of moist air to the mass of water
vapour in the same volume of saturated air at the same temperature and pressure.8 It is measured as the percentage
of moisture present in the air as compared to its full capacity/the maximum moisture it can hold at a given temperature.
With a change in air temperature, the capacity to retain moisture increases or decreases, thus affecting relative humidity.

6. Specific Humidity: The mass of water vapour present in 1 kilogramme (kg) of dry air. It is also called specific humidity
or humidity ratio. Generally, the unit is g/kg of dry air.9

1
Dincer, I. & Rosen, M. A., 2007. Chapter 6 - Exergy Analysis of Psychrometric Processes. EXERGY, Elsevier, pp. 76-90.
2
Govekar, N., Bhosale, A., & Yadav, A., 2015. Modern Evaporative Cooler. International Journal Of Innovations In Engineering Research And Technology [IJIERT], 2(4).
3
Gatley, D. P., 2013. Understanding Psychrometrics, Atlanta: American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE).
4
 eitelbaum, E., Jayathissa, P., Mil, C., & Meggers, F., 2019. Design with Comfort: Expanding the psychrometric chart with radiation and convection dimensions. Energy & Buildings,
T
Elsevier.
5
Gatley, D. P., 2013. Understanding Psychrometrics, Atlanta: American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE).
6
Ibid.
7
REHVA, 2012. Definitions of terms and abbreviations commonly used in REHVA publications and in HVAC practice, s.l.: REHVA.
8
Govekar, N., Bhosale, A., & Yadav, A., 2015. Modern Evaporative Cooler. International Journal Of Innovations In Engineering Research And Technology [IJIERT], 2(4).
9
Ibid.

12 // Decoding Evaporative Air Coolers

Key Definitions // 13
Executive Summary
Achieving thermal comfort is essential to ensure overall wellbeing and
increasing productivity. India is one of the countries with the lowest access
to cooling globally but simultaneously has around 4 trillion person cooling
degree days. Currently, only a small fraction of the total residential population
has access to air conditioners, and a significant share of households will still
not have access to air conditioners over the next 10-20 years, due to lack of
purchasing power, for achieving thermal comfort.
Despite air conditioners’ low penetration, they contribute significantly to
emissions based on their energy use as they use high Global Warming
Potential (GWP) refrigerants, peak demand in metropolitan cities and space
cooling energy consumption which is predicted to rise significantly by 2037-
38. Therefore, India is facing the challenge of providing access to affordable
cooling for all, while simultaneously mitigating climate change.
With India’s tropical climatic conditions and pressing climate need for cooling,
there is a significant opportunity to increase the uptake of evaporative air coolers
in India’s appliance market. Evaporative air coolers could play a significant
role in providing thermal comfort for all while also reducing the demand for
refrigerants with GWP in India. They are a sustainable and affordable cooling Evaporative air coolers
technology alternative, when compared to air conditioners, as they work on the could play a significant role
simple principle of evaporation, where water is used as a natural refrigerant, in providing thermal comfort
and they function well in India’s hot-dry and composite climatic zones. In for all while also reducing
comparison to air conditioners, evaporative air coolers are more affordable, the demand for refrigerants
consume less energy, have low operational and maintenance costs, and are a with GWP in India.
Non-GWP refrigerant based space cooling solution.
In order to facilitate evaporative air cooler market growth, there is a critical
need to promote and facilitate the penetration of standardised and energy-
efficient evaporative air coolers by developing their Minimum Energy
Performance Standards (MEPS). Henceforth, this study focused on the national
and international policy, regulatory, and institutional frameworks related to
evaporative air cooler performance through an extensive literature review.
The study also highlighted the gaps and recommendations for India, based
on the learnings from international evaporative air cooler testing standards,
regulations, and MEPS frameworks.
The study provided detailed information on the different types of evaporative
air coolers—direct evaporative air coolers (DECs), indirect evaporative air
coolers (IECs), and indirect-direct evaporative air cooler (IDECs)—based on
their structure, technology description, working principle, and applications. In
DECs, cooling pads are used as the cooling medium, and the cooled air has
increased humidity. DECs are more efficient than IECs. In this technology, the
dry-bulb temperature decreases, whereas the wet-bulb temperature remains
constant, and there is no change in enthalpy. This type of evaporative air
cooler is best suited to the residential sector and hot-dry climatic zones.
The IECs, in contrast, use heat exchangers as their cooling medium. In this
technology, no humidity is added to the supply air, and there is a reduction
in enthalpy and the dry- and wet-bulb temperatures. This technology is best
suited to both the residential and commercial sectors and is adaptable in
composite/hot-dry climatic zones.
An IDEC combines an IEC, in the first stage, and a DEC, in the second stage. It
is the most efficient technology in comparison to the other two types. Humidity
is added to the supply air, but the increase in humidity is lower than in DECs. In
this technology, there is a reduction in enthalpy and the dry-bulb temperature.
The wet-bulb temperature initially decreases in the first stage and then remains
constant in the second stage.

14 // Decoding Evaporative Air Coolers

This technology is best suited to both the commercial and industrial sectors
and is adaptable in composite/hot-dry climatic zones.
The study also provided a brief overview of the Indian evaporative air cooler
market and institutional framework. Currently, India’s unorganised evaporative
air cooler market has a larger market share than the organised market.
The unorganised sector uses offline market distribution channels and retail
shops, whereas the organised sector employs both offline and online market
India’s unorganised
distribution channels. The evaporative air cooler market is segmented into
evaporative air cooler
residential and commercial, according to the cooler application. Preliminary
market has a larger market
stakeholder consultations indicated that DECs are majorly in demand in the
share than the organised
residential sector, and the demand for IDECs is expected to grow multifold in
market.
the commercial and industrial sector in the near future due to potential IDEC
applications and lower energy consumption in comparison to air conditioners.
The institutional framework for appliances in India is governed by various
ministries, regulatory bodies, state agencies and associations, including the
Ministry of Power (MoP), Ministry of Commerce & Industry (MoCI), Ministry of
Environment, Forest & Climate Change (MoEF&CC), Ministry of Electronics &
Information Technology (MeitY), Ministry of Consumer Affairs, Food, and Public
Distribution, Bureau of Energy Efficiency (BEE), Bureau of Indian Standards
(BIS), India Brand Equity Foundation (IBEF), Central Power Research Institute
(CPRI), State Electricity Regulatory Commissions (SERCs), State Designated
Agencies (SDAs), Indian Society of Heating, Refrigerating and Air Conditioning
Engineers (ISHRAE)and Consumer Electronics and Appliances Manufacturers
Association (CEAMA). These organisations could potentially play a role in the
implementation of MEPS for evaporative air coolers.
Moreover, the study also examined the Indian Standard (IS) for evaporative air
coolers and energy efficiency programmes focused on increasing appliance
efficiency in India. As per the latest IS standard for evaporative air coolers, the
airflow, outer structure material, noise levels, cooling pads, and fan motor and
water pump efficiency are the most critical parameters for evaluating a cooler’s
overall performance. Water consumption is not included as a parameter in this
standard. The study also looked at the national programmes aiming to enhance
appliance efficiency—the BEE Standards and Labelling (S&L) programme and
National Mission for Enhanced Energy Efficiency (NMEEE).
The literature review on India’s policy, regulatory, and institutional framework
revealed significant scope for improvement. Hence, there was a need to look
at international best practices in improving evaporative air cooler energy
efficiency, in order to extract learnings and develop a more robust policy,
regulatory, and institutional framework for evaporative air coolers in India.
For the international review, Iran, USA (California), and Australia were selected, Only Iran has established
and their policies, regulations, testing standards, and MEPS for evaporative MEPS for evaporative air
air coolers were analysed. In addition to this, American Society of Heating, coolers.
Refrigerating and Air-Conditioning Engineers (ASHRAE) testing standards
for both DECs and IECs were also examined, along with Eurovent Certita
Certification (ECC) initiatives for increasing the performance. All the international
standards/regulations cover power consumption, airflow, and cooling/
saturation effectiveness. However, only ASHRAE and ECC have touched upon
parameters related to water efficiency, and only Iran has established MEPS for
evaporative air coolers.
Based on the comprehensive review of national and international institutional,
policy, and regulatory frameworks in regards to improving the performance of
evaporative air cooler, the study identified gaps at the national level in terms
of ‘policy and regulatory’ and ‘research and design’ which are followed by
recommendations to address them in the near future.

Executive Summary // 15
1
Introduction
This chapter provides the context for this study by
highlighting the challenge faced by India to provide
access to sustainable thermal comfort for all and
the need for promoting the use of an alternative
sustainable cooling technology.
1.1 | Background
Access to cooling for attaining thermal comfort is no
longer a luxury, but, rather, a necessity for enhancing
overall quality of life, productivity, and well-being.
Thermal comfort can be defined as a state where an
individual is satisfied with the thermal environment, which
is determined and affected by various factors, such as the
microclimatic conditions—temperature, relative humidity,
airflow, air temperature, dew-point temperature, and
wind speed— and an individual’s clothing insulation & India has one of the lowest levels of
metabolic rate10&11. Achieving and experiencing thermal access to cooling, with per capita space
comfort is essential for an individual’s psychological and cooling energy consumption at

69
physiological well-being.
A country’s cooling demand depends on multiple
variables, the most vital being the country’s per capita
kilowatt-hours (kWh),
Gross Domestic Product (GDP), population, and cooling
degree days. India is one of the largest and fastest- compared to the world average of 272
growing economies in the world, with over 3,000 cooling kWh.
degree days per year12. Despite the growing economy
and pressing climatic need for cooling, according to the
India Cooling Action Plan (ICAP) 2019, India has one of the
lowest levels of access to cooling, with per capita space
cooling energy consumption at 69 kilowatt-hours (kWh),
compared to the world average of 272 kWh.

10 
ASHRAE, 2017. STANDARD 55 – Thermal Environmental Conditions for Human Occupancy. [Online] Available at: https://www.ashrae.org/technical-resources/bookstore/standard-
55-thermal-environmental-conditions-for-human-occupancy
11
Sustainable and Smart Space Cooling Coalition, 2017. Thermal Comfort for All - Sustainable and Smart Space Cooling, New Delhi: Alliance for an Energy Efficient Economy.
12 
Lalit, R. & Kalanki, A., 2019. How India is solving its cooling challenge. [Online] Available at: https://www.weforum.org/agenda/2019/05/india-heat-cooling-challenge-temperature-
air-conditioning/[Accessed 2020].

18 // Decoding Evaporative Air Coolers

 Person cooling degree days (million)
4,500,000

4,000,000

3,500,000

3,000,000

2,500,000

2,000,000

1,500,000

1,000,000

500,000

Japan United Korea China Mexico Brazil Indonesia India Nigeria Egypt
States

Person cooling degree

days

Figure 1: Global Comparison of Person Cooling Degree Days 13

As per a recent study by Rocky Mountain Institute (RMI)14, transition. Therefore, India is currently facing the challenge
India has around 4 trillion ‘person cooling degree days’15, of providing access to affordable cooling for all without
which is significantly higher than that of other countries, exacerbating environmental issues.
as shown in Figure 1. However, only 7-9% of the Indian
In India, interventions such as the Hydrochlorofluoro-
households currently own room air conditioners, and it is
carbons (HCFCs) Phase Out Management Plan (HPMP)
estimated that even in the coming decade, a significant
Phase 1 has been successfully completed for some sub-
share of households will still not have sufficient purchasing
sectors, namely, Variable Refrigerant Flow (VRF) Products,
power to buy room air conditioners, for attaining thermal
Rail Coach Air-Conditioning (AC), Bus AC, and Transport
comfort16. Despite the fact that room air conditioners
Refrigeration under room air conditioner manufacturing
have low penetration in Indian households, they use
industry21. However, it will take significant time to phase
refrigerants, which have high17 global warming potential out the existing products with HCFCs from the Indian
(GWP) accounting for a significant share of emissions room air conditioner market and built environment, which
based on their energy use18. is now being aggressively carried out under HPMP Phase
Furthermore, room air conditioners still account for 2 (2017-2023).
a dominant share of Indian space cooling energy India has five climatic zones consisting of hot-dry, warm
consumption—around 42% in 2017-18, which is expected & humid, temperate, composite, and cold22. Considering
to steadily grow to ~52% in 2037-38—and are currently India’s tropical climatic conditions and the impact of
contributing around 50% of the peak load, specifically room air conditioners on power consumption, along with
in major metropolitan areas of India19&20. At the same the associated greenhouse gas (GHG) emissions, there
time, India has ratified the Kigali Amendment on the use exists a significant opportunity to promote evaporative air
of refrigerants with high GWP, which calls for the pursuit coolers.
of enhanced energy efficiency amidst the refrigerant

13 
Adapted from Lalit, R. & Kalanki, A., 2019. Cooling Demand Versus Current AC Ownership in Different Parts of The World. [image] Available at: https://www.weforum.org/
agenda/2019/05/india-heat-cooling-challenge-temperature-air-conditioning[Accessed 17 January 2020].
14 
Lalit, R. & Kalanki, A., 2019. How India is solving its cooling challenge. [Online] Available at: https://www.weforum.org/agenda/2019/05/india-heat-cooling-challenge-temperature-
air-conditioning/[Accessed 2020].
15 
A cooling degree day is a measurement to estimate the demand for energy needed to cool a building. Person cooling degree days represent a country’s average annual
cooling degree days multiplied by the total population.
16 
Ministry of Environment, Forest & Climate Change, 2019. India Cooling Action Plan, New Delhi: Ministry of Environment, Forest & Climate Change.
17 
‘High’ here refers to refrigerants that have a GWP above 750. As per ISHRAE’s 2015 data, the most commonly used refrigerant in India is HFC 134a, which has the GWP of 1340.
18 
Ministry of Environment, Forest & Climate Change, 2019. India Cooling Action Plan, New Delhi: Ministry of Environment, Forest & Climate Change.
19
Ibid.
20 
Pandita, S., Kishore Kumar, P., Walia, A., & Ashwin, T., 2020. Policy measures and impact on the market for the Room Air. [Online]. Available at: https://clasp.ngo/publications/
policy-measures-and-impact-on-the-market-for-room-air-conditioners-in-india
21 
Ministry of Environment, Forest & Climate Change, 2017. HCFC Phase-Out Management Plan Stage II, New Delhi: Ministry of Environment, Forest & Climate Change.
22 
Bureau of Indian Standards, 2016. National Building Code of India 2016 Volume 2, New Delhi: Bureau of Indian Standards.

Introduction // 19
Evaporative air coolers can prove to be an effective alternative technology because it uses a sustainable and affordable
Non-GWP refrigerant based cooling mechanism to ensure thermal comfort and works reasonably well in Indian climatic
conditions, with its only limitation being extremely humid conditions. Evaporative air coolers would not only reduce the
user’s dependency on room air conditioners with high GWP, but would also help India meet its nationally determined
contribution (NDC), i.e. the 2030 targets for emission reduction, along with its commitments made in the Kigali agreement.
This would also align with goals set in the ICAP.
Evaporative air coolers are also known as swamp or desert coolers and have applications in both residential and
commercial settings. They work on the simple principle of evaporation of water, where water also acts as a refrigerant.
Several studies and literatures have indicated that evaporative air coolers can effectively provide thermal comfort in
India’s two major climatic zones, hot-dry and composite, covering the majority of the country, as shown in Figure 223,24&25.

Evaporative Air Coolers are generally

80-85%%
cheaper and consume

Climate Zones

Hot-dry
Composite
80-90%%
less electricity than air conditioners
Other Zones

Figure 2: Climate Zones in India Where Evaporative Air

Coolers Work Effectively 26

In addition to being a Non-GWP refrigerant based space India’s evaporative air cooler market is projected to grow
cooling solution and adaptable to India’s tropical climatic at a Compound Annual Growth Rate (CAGR) of 14.2% in
conditions, evaporative air coolers are an affordable 2019-2530. With their growing demand and evaporative
and sustainable cooling technology alternative. They air coolers’ approximate lifespan of 12 years or more,
are generally 80-85% cheaper and consume 80-90% there is a critical need to develop their Minimum Energy
less electricity than air conditioners27&28. Furthermore, Performance Standards (MEPS) in order to lock in energy
new age evaporative air coolers with energy-efficient savings in the coming years, thus creating a level playing
fans and pumps have an energy saving potential of field and encouraging the adoption of energy-efficient
an additional 10-20% in the coming decade, when evaporative air coolers.
compared to business as usual case29. Evaporative
air coolers could facilitate provision of thermal comfort
for all, while simultaneously reducing the demand for
refrigerants with GWP in India.

23 
Jain, J. & Hindoliya, D., 2013. Energy saving potential of indirect evaporative cooler under Indian climates. International Journal of Low-Carbon Technologies 2016, p. 193–198.
24 
Sarkar, J., 2020. Evaporative Cooling Technologies for Buildings, Varanasi: Cooling India.
25 
Govekar, N., Bhosale, A., & Yadav, A., 2015. Modern Evaporative Cooler. International Journal Of Innovations In Engineering Research And Technology [IJIERT], 2(4).
26
Adapted from Bureau of Indian Standards, 2016. National Building Code of India 2016 Volume 2, New Delhi: Bureau of Indian Standards.
27 
Grand View Research, 2019. Air Coolers Market Size, Share & Trends Analysis Report By Type (Tower, Dessert), By Application (Residential, Commercial), By Region (North
America, Europe, APAC, CSA, MEA), And Segment Forecasts, 2019 - 2025, California: Grand View Research.
28
Jain, A., 2020. Bijli Bachao. [Online] Available at: https://www.bijlibachao.com/air-conditioners/best-air-cooler-india-brand.html [Accessed 2020].
29
Ministry of Environment, Forest & Climate Change, 2019. India Cooling Action Plan, New Delhi: Ministry of Environment, Forest & Climate Change.
30 
6Wresearch, 2019. India Air Cooler Market (2019-2025). [Online] Available at: https://www.6wresearch.com/industry-report/india-air-cooler-market-2019-
2025#:~:text=According%20to%206Wresearch%2C%20India%20Air,with%20the%20demonetization%20in%202016.

20 // Decoding Evaporative Air Coolers

1.2 | Objective
This study is envisioned to act as a catalyst for influencing
policymakers to facilitate improvements in evaporative air
cooler performance and standardise the existing market
through the development of the MEPS framework for
evaporative air coolers in India. This study is the part of
AEEE’s on-going effort ‘SHEETAL31’, which is focused towards
facilitating the ICAP implementation. In the long term, India’s evaporative air cooler market is
the study will facilitate increased access to efficient and projected to grow at a Compound Annual
sustainable space cooling technologies to achieve thermal Growth Rate (CAGR) of

14.2%%
comfort by promoting the use of standardised evaporative air
coolers. It will also contribute to the wider market adoption
and mainstreaming of Non-GWP refrigerant based space in 2019-25
cooling technologies in India.

This study aims to map and provide an in-depth understanding

of national and international policy, regulatory,
and institutional frameworks focused on increasing the
energy performance of evaporative air coolers. Through
an extensive literature review, the study identifies
prevailing gaps in the existing national framework and
provides recommendations for India based on the
learnings from the assessment of international testing
standards and MEPS frameworks for evaporative air
coolers. As a point of departure, one must have an
understanding of evaporative air cooler technology, which is
presented in the following chapter.

Alliance for Sustainable Habitat Energy Efficiency and Thermal Comfort for All (SHEETAL). “SHEETAL is a consortium of CSOs led by TERI and partners AEEE, CEEW and
31 

supported by Children Investment Fund Foundation to facilitate the implementation of India Cooling Action Plan (ICAP) recommendations”.

Introduction // 21
2
Understanding Evaporative
Air Coolers: Technology &
Market Assessment
This chapter begins with a comparison of the
benefits of evaporative air coolers versus
conventional air conditioners in terms of providing
thermal comfort. It then takes a deep dive into
the types of evaporative air coolers based on
their structure, technology, working principle, and
applications. This chapter concludes with a brief
overview of the market outlook for evaporative air
coolers in India.
2.1 | Evaporative Air Coolers vs Conventional Air
Conditioners
Evaporative air coolers can effectively provide thermal comfort in hot-dry and composite climatic zones, as they
work on the principle of evaporation, leading to an exchange of heat and mass during this process. The air that is
drawn into the evaporative air cooler passes through the ‘cooling pads’, and, simultaneously, the pump circulates the
water, which acts as a refrigerant, over the cooling pads. The water absorbs the heat from the warm air, resulting in
evaporation of water, and then the fan releases fresh cooled air into a space. If an evaporative air cooler is drawing
air from ambient surroundings, it brings in 100% outdoor air into an indoor setting which helps maintain the indoor air
quality (IAQ)32&33.

In contrast, conventional air conditioners cool down the recirculated air, which increases the chances of breathing
in contaminated air. Nevertheless, conventional air conditioners are somewhat more effective cooling appliances
than evaporative air coolers, as, in addition to cooling the air, they also dehumidify the supply air and thus create
a more comfortable indoor environment for the user by cooling and dehumidification. However, conventional air
conditioners come with high installation, operational, and maintenance costs. Moreover, as mentioned in Chapter
1, the refrigerants used in these air conditioners have high GWP, meaning they are harmful for the environment. In
comparison, evaporative air coolers are more affordable, have low operation and maintenance costs, consume less
energy, and are a Non-GWP refrigerant based space cooling technology. Thus, evaporative air coolers have higher
market growth potential in terms of their application for achieving thermal comfort without impacting the environment.
The next section examines evaporative air cooler technology.

32 
Jain, A., 2020. Bijli Bachao. [Online] Available at: https://www.bijlibachao.com/air-conditioners/best-air-cooler-india-brand.html [Accessed 2020].
33
 aschold, H., Li, W.-W., Morales, H., & Walton, J., 2003. Laboratory study of the impact of evaporative coolers on indoor PM concentrations. Atmospheric Environment, Elsevier, p.
P
1075–1086.

24 // Decoding Evaporative Air Coolers

2.2 | Evaporative Air Coolers
Evaporative air coolers are also known as swamp or desert coolers
and have applications in both residential and commercial settings.
They use water (R718), which is a natural refrigerant34. Evaporative air
coolers are used to cool the air through the fundamental principle
of evaporation of water. They provide cooled air with added specific
humidity. Evaporative air coolers can effectively and efficiently
Evaporative Air Coolers use

water
operate and provide thermal comfort in hot-dry and composite
climates. However, they cannot operate effectively in areas with
higher humidity, as the evaporation process slows down due to
the presence of high relative humidity in the air or air being highly (R718)
(R718)
saturated. Furthermore, in arid areas, they may exacerbate water which is a natural refrigerant
scarcity, since they require water to operate. However, this is still
preferable to conventional air conditioners, as air conditioners are
quite energy-intensive and require energy from thermal power plants,
which, in turn, require a lot of water to operate. Moreover, not all such
plants have good water recovery.

Evaporative air coolers work effectively in adequately or naturally

ventilated spaces, but cannot work in closed spaces, as they need
to maintain the flow of fresh air to sustain the continuous process
of evaporation. There are three types of evaporative air coolers, as
shown below in Figure 335.

Direct Evaporative air

Cooler (DEC)

Indirect Evaporative air

Cooler (IEC)

Indirect - Direct
Evaporative air Cooler
(IDEC)

Figure 3: Types of Evaportive Air Coolers

Water is environmentally friendly, thermodynamically attractive, safe i.e. non-toxic, non-flammable and a natural refrigerant.
34 

Amer, O., Boukhanouf, R., & Ibrahim, H. G. A., 2015. A Review of Evaporative Cooling Technologies. International Journal of Environmental Science and Development, Volume
35 

V6.571.

May 2021 // 25
Understanding Evaporative Air Coolers: Technology & Market Assessment
2.2.1 | D irect Evaporative Air
Coolers
Structure - Components and Their
Functions:
A direct evaporative air cooler (DEC)
consists of cooling pads, blower
fan, water reservoir tank, water
distributor, pipe, pump, and float
valve, as shown in Figure 4.

Figure 4: Basic Structure of a DEC36

The above-mentioned components of an evaporative air cooler have the following functions:

Pump: The pump helps circulate B

 lower Fan: The blower fan circulates C
 ooling pad: The cooling pads hold
water from the water tank to the and maintains the airflow within water and are fitted on the sides of
cooling pads. When the appliance is the room. The blower fan creates the cooler, ensuring that outside air
switched on, the pump immediately airflow at low pressure; however, it is passes through these pads and is
starts operating, followed by the efficacious to be used in large room cooled. The cooling pad can be cross-
blower fan. settings. The blower fan draws in air fluted or have a honeycomb structure.
from the outside and supplies cooled
air to the room.

Water reservoir tank: The water Water distributor and pipe: The
reservoir tank is used to store pipe is used to circulate water, with
the water supplied to the cooling the help of the pump, from the water
pads. It is filled either manually or reservoir to the water distributor,
automatically, depending on the which ensures even distribution of
type of the evaporative air cooler. water over the cooling pads.

Float Valve: The float valve enables Drain Valve: The drain valve, as
freshwater intake, checks the tank’s the name suggests, is used to drain
water level, and prevents water the water from the evaporative air
overflow. cooler’s float valve as required.

Piattelli, C., 2016. Evaporative cooling. Powrmatic. Available at: https://www.powrmatic.co.uk/blog/evaporative-cooling-work/

36 

26 // Decoding Evaporative Air Coolers

Technology Description:
This technology works on the basis of heat and mass transfer between air
and water. Direct evaporative air coolers help reduce the air temperature
through the process of evaporation of water along with the conversion of
sensible heat into latent heat. During this process, the air passes through
the cooling pad of the evaporative air cooler leading to direct contact This technology works
between air and water. This leads to the addition of humidity in the cooled on the basis of heat and
supply air. DECs can operate effectively in dry climatic zones, but are not mass transfer between
recommended in places with high humidity or low dry-bulb temperature. air and water. Direct
This is because the ambient air in climatic zones with high humidity is highly evaporative air coolers
saturated, and, thus, the evaporation process slows down, rendering the help reduce the air
DECs ineffective. temperature through the
process of evaporation
of water along with the
Working Principle:
conversion of sensible
The outside warm and dry air with sensible heat is drawn into the DEC and heat into latent heat.
passes through the cooling pads, as shown below in Figure 5 & Figure 6.

Figure 5: Sensible and Latent Heat in Evaporative Air Cooling Process 37 Figure 6: Working of a DEC 38

As the dry and warm air passes through the cooling pads, the pump
circulates and distributes water over the cooling pads. The water then
absorbs the heat from the air resulting in the evaporation of water along
with the conversion of sensible heat into latent heat, as shown above in
Figure 5 & Figure 6, which cools down the air’s dry-bulb temperature.
During this process, humidity is added to the cooled air. The cooled air, with
reduced dry-bulb temperature (because of the reduction in sensible heat)
and added humidity, is then released into the room by a motor-driven fan.
The wet-bulb temperature of air remains constant.

37
Piattelli, C., 2016. Latent Energy Vs Sensible Energy. Powrmatic. Available at: https://www.powrmatic.co.uk/blog/evaporative-cooling-work/
38 
Fairconditioning. Engineering Principle – Direct Evaporative Cooling, Evaporative Cooling. Fairconditioning. Available at: http://fairconditioning.org/knowledge/sustainable-
cooling-technologies/evaporative-cooling/#1500296799628-e5546709-43d940f0-dcf0

Understanding Evaporative Air Coolers: Technology & Market Assessment // 27

 Dry-bulb Temperature,oC
(Increases from Left to Right)

Performance Estimation:
T: Dry-bulb temperature DEC efficiency is based on the following42:
W: Wet-bulb temperature

Specific Humidity, g/kg

1-2: First Stage
2
W2 2-3: Second Stage
T: Dry-bulb temperature
1 W: Wet-bulb temperature
W1 Air velocity (supply Type of cooling

(Increases from bottom to top)

Specific Humidity, g/kg
airflow rate) pad/media
3
W3
W1,W2
2 1
T2 T1

Dry-bulb Temperature, oC
Depth of cooling Climatic conditions
pad/media T3 T2 T1

Dry-bulb Temperature,oC
Figure 7: Psychrometric Chart of a DEC 39 (Increases from Left to Right)

The following formula can be used to calculate the

The psychrometric chart in Figure 7 above shows that maximum possible temperature-drop43:
due to evaporation, air moves towards the saturation
DBS= (DBA – WBA) X Cooling Pad Efficiency
or wet-bulb temperature, i.e. from 1 to 2, due to a
reduction in dry-bulb temperature, increased humidity, Where:
and constant wet-bulb temperature. Evaporation, DBS: Temperature drop of supply air
along with latent heat, results in evaporative cooling.
DBA: Dry-bulb temperature of ambient air
Therefore, in DECs, there is a trade-off between the
reduced air’s dry-bulb temperature and increased WBA: Wet-bulb temperature of ambient air
humidity, resulting in no net change in enthalpy—the (DBA – WBA): The wet-bulb depression, i.e. the
sum of sensible and latent heat—in the air. A DEC’s lowest temperature that can be achieved through
wet-bulb effectiveness40 ranges from ~70% to 95%41, evaporation.
as there is direct contact with water and an exchange
of mass.
Thermal comfort is dependent on both humidity and
temperature, but it is more commonly understood to
be dependent on relative humidity (RH). The ability
of air to hold water—and, thus, its relative humidity—
depends on the air’s temperature. If the air temperature
is high (warm air), it can hold more water through rapid
A DEC’s wet-bulb effectiveness ranges from
evaporation, as the air has less RH. In contrast, if the

~~70%
% toto 95%
air temperature is low (cool air), it is saturated and
already has high RH. Thus, it cannot hold more water;
in this case, evaporation will either not take place or
be very slow. Therefore, DECs work effectively in hot-
%
dry or composite climatic zones with high temperature as there is direct contact with water and an
and low humidity. exchange of mass.

39
 arkar, J., 2020. Layout of DCE and processes on psychrometric chart. Cooling India. Available at: https://www.coolingindia.in/evaporative-cooling-technologies-for-
S
buildings/#:~:text=In%20the%20hot%2Ddry%20climatic,undergoes%20a%20composite%20climate%20zone.
40 
The maximum temperature drop that is possible through evaporation. It is also referred to as the evaporation or saturation effectiveness/efficiency or evaporative cooling
effectiveness.
Amer, O., Boukhanouf, R., & Ibrahim, H. G. A., 2015. A Review of Evaporative Cooling Technologies. International Journal of Environmental Science and Development, Volume
41 

V6.571.
42 
fairconditioning, 2019. Evaporative Cooling. [Online] Available at: http://fairconditioning.org/knowledge/sustainable-cooling-technologies/evaporative-cooling/#1500552370074-
430ff37c-6e5440f0-dcf0
43 
Ibid.

28 // Decoding Evaporative Air Coolers

Types of DECs:

Spray/air washer
Basis of water
distribution Slinger/rotating wheel
system
Drip/Misting system

Cooling pads made up of

Active Random media DEC plastic fiber/foam supported by
Evaporative Air Cooling Strategies

plastic frame

Basis of Cooling pads made up of

Evaporative Rigid media DEC Blocks of corrugated materials:
medium Cellulose, plastic and fiberglass

Rigid cooling pads mounted on

Remote media DEC
wall or roof of building

Mashrabiya wooden screens/windows provides shade

Passive
water pool in plastic or fiber-glass
Roof-pound
container is stored on top of the roof

Figure 8: Evaporative Air Cooling Strategies 44

DECs can be further classified into the following types power consumption. They cool down the building
based on their operational power consumption45: temperature through passive strategies, and these
strategies differ as per the climatic conditions, such
• Active DEC systems require electrical power to
as mashrabiya and roof-pound, as described above
function. As per the ASHRAE Handbook-HVAC
in Figure 8.
Systems and Equipment 2008, they can be further
classified according to the type of evaporative As per the information available on various e-commerce
medium used and water distribution system, as shown websites such as Amazon and Indiamart and the
above in Figure 8. websites of individual manufacturers, the average
capacity range of DECs sold by the key manufacturers,
• Passive DEC systems are building design concepts.
such as Symphony and Bajaj, is 10-120 Litres (L).
They are naturally operated systems with zero

44
 dapted from Amer, O., Boukhanouf, R., & Ibrahim, H. G. A., 2015. A classification of evaporative cooling systems in building cooling. Available at: https://www.researchgate.net/
A
publication/265890843_A_Review_of_Evaporative_Cooling_Technologies?enrichId=rgreq-6d19e6de5aa5b93ace10bbb7df1b0364-
45 
Amer, O., Boukhanouf, R., & Ibrahim, H. G. A., 2015. A Review of Evaporative Cooling Technologies. International Journal of Environmental Science and Development, Volume
V6.571.

Understanding Evaporative Air Coolers: Technology & Market Assessment // 29

DEC Applications:
DECs have various applications, as mentioned below, for providing thermal comfort to the occupants, leading to an
increase in productivity and reduction in problems related to heat-stress.46:

Residential cooling Commercial small-scale office cooling Industrial cooling

Figure 9: Applications of a DEC

2.2.2 | Indirect Evaporative Air Coolers

Structure:
An indirect evaporative air cooler (IEC) comprises a heat
exchanger, blower fan, water tank, water distribution
system including a water distributor and pipe, and pump
(as shown in Figure 10). The functions of these components
are the same as defined above in Section 2.2.1, except the
additional component, the heat exchanger (HE), which is
explained below:
• Heat exchanger: A device that enables heat transfer
between water and air, without keeping them in
direct contact47.

Figure 10: Schematic of an IEC 48

Fairconditioning, 2019. Evaporative Cooling. [Online] Available at: http://fairconditioning.org/knowledge/sustainable-cooling-technologies/evaporative-

46 

cooling/#1500552344002-ba9ef76c-c3a440f0-dcf0
Zohuri, B., 2018. Chapter 12 - Heat Exchangers. Physics of Cryogenics, pp. 299-330
47 

30 // Decoding Evaporative Air Coolers

Technology Description:
The primary difference between an IEC and a DEC is that
an IEC contains a sensible HE instead of cooling pads.
The HE contains two streams: wet air streams and dry air
steams, as shown in Figure 11. Unlike the direct evaporative
coolers, the HE in the IEC keeps the air and water separate;
there is no direct contact between air and water. This
technology helps in reducing the air temperature through
heat exchange and without adding humidity in the supply
air. In this process, the exchange of heat takes place with
no exchange of mass. In contrast to DECs, IECs can operate
effectively in humid climatic zones.

Working Principle:
The warm air through the secondary air stream is
channeled through the wet air stream panels in the HE,
where water is percolating in from the top. This leads
to evaporation of water; air containing moisture starts to
exit from the sensible HE out through an exhaust fan, as
shown in Figure 11 and Figure 12. During this process, the
water cools down and is then used to indirectly cool the
inlet primary air.
Simultaneously, the warm air from the primary air stream
Figure 11: Working of an IEC 50
is channeled through the dry air stream panels (with
cooled surface/HE panels) through the HE, resulting in
cooling down of air due to the transfer of heat between
Chapter 2
the cooled HE panels and warm air. This cooled air is
supplied to the room, with no added specific humidity.
Specific humidity in the supply air remains the same as it
was there in the inlet primary air; there is no addition or
T: Dry-bulb temperature
reduction in specific humidity. W: Wet-bulb temperature

The maximum cooling through IECs is possible until the

(Increases from bottom to top)

Specific Humidity, g/kg
3 W3
secondary air stream reaches its wet-bulb temperature,
i.e. its saturation level. Therefore, IECs’ evaporation 2 1
W1,W2
effectiveness is lower than that of DECs, ranging from
~40% to 80% .
49

T3 T2 T1

Dry-bulb Temperature,oC
(Increases from Left to Right)

IECs’ evaporation effectiveness is lower

than that of DECs, ranging from Figure 12: Psychrometric Chart of an IEC 51

~~40%
% toto 80%
T: Dry-bulb temperature
W: Wet-bulb temperature

%
Specific Humidity, g/kg

1-2: First Stage

2
W2 2-3: Second Stage
T: Dry-bulb temperature
1 W: Wet-bulb temperature
W1
Amer, O., Boukhanouf, R., & Ibrahim, H. G. A., 2015. IEC structure. Available at: https://www.researchgate.net/publication/265890843_A_Review_of_Evaporative_Cooling_
48 

Technologies?enrichId=rgreq-6d19e6de5aa5b93ace10bbb7df1b0364-XXX&enrichSource=Y292ZXJQYWdlOzI2NTg5MDg0MztBUzoxNjUxOTgyMjg4OTM2OTdAMTQxNjM5NzczN
Tk5Nw%3D%3D&el=1_x_3&_esc=publicationCoverPdf 3
Amer, O., Boukhanouf, R., & Ibrahim, H. G. A., 2015. A Review of Evaporative Cooling Technologies. International Journal of Environmental Science and Development, Volume
49 

V6.571.
50 
Adapted from Fairconditioning. Engineering Principle – Indirect Evaporative Cooling, Evaporative Cooling., Fairconditioning. Available at: http://fairconditioning.org/knowledge/ 2
sustainable-cooling-technologies/evaporative-cooling/#1500296799628-e5546709-43d940f0-dcf0 2
T T1
Sarkar, J., 2020. Layout of active IEC and processes on psychrometric chart. Cooling India. Available at: https://www.coolingindia.in/evaporative-cooling-technologies-for-
51 

Dry-bulb Temperature, oC
buildings/#:~:text=In%20the%20hot%2Ddry%20climatic,undergoes%20a%20composite%20climate%20zone.

T T2
Understanding Evaporative Air Coolers: Technology & Market Assessment // 31 3
Dry-bulb Temperature,oC
As the moisture content remains constant with the decrease in the air’s dry-bulb temperature, the air’s wet-bulb
temperature also decreases. On a psychrometric graph, in an IEC, air moves toward its saturation temperature, i.e.
from 1 to 2, instead of from 1 to 3, as shown in Figure 12, as there is:
• Reduction in dry and wet-bulb temperatures
• Reduction in enthalpy of the air as there is a reduction in the sensible heat, but no specific humidity is added to the
supply air

Performance Estimation:
IEC efficiency is dependent on the following52:

Air velocity (supply Type of heat Secondary air or Use of outside Climatic conditions
airflow rate) exchanger water flow air or exhaust of
secondary air

Types of IECs:
IECs can be further classified into the following types based on their operational power consumption53:

IECs

Wet-bulb Temperature IEC Sub-wet-bulb Temperature IEC

Figure 13: Types of an IEC

Wet-Bulb Temperature IEC System: This system consists of Sub-Wet-Bulb Temperature IEC System: This system
flat-plates that are stacked together acting as the cross-flow consists of a cross-flow heat exchanger and multi-perforated
heat exchanger. This type of IEC helps decrease the supply flat-plate. This type of IEC further enhances the effectiveness
air’s dry-bulb temperature to close to the inlet air’s wet-bulb of the wet-bulb temperature IEC system as it reduces the
temperature, but not below it, depending upon the type of supply air’s temperature to below the inlet air’s sub-wet-bulb
heat exchanger used—the different wet-bulb temperature temperature. The working principle behind this system is that
IEC types are heat pipe, plate-type, and tubular-type the secondary air stream is first precooled in the dry air stream
IEC. The working principle behind this system is that there panels before entering the wet air stream panels for further
are several pairs of wet and dry air stream panels placed heat transfer, thus cooling the HE plates. Simultaneously, the
adjacent to one another. The warm air from the primary air primary air stream is channeled through the dry air stream
stream passes through the dry air stream panels, and the panels, which are being cooled by the precooled secondary
warm air from the secondary air stream passes through the air stream; this further enhances the cooling process, and no
wet air stream panels, as shown in Figure 11, which results in specific humidity is added into the cooled supply air55.
heat transfer in the wet-bulb temperature IEC system through IECs are generally available in Indian market in the range of
a heat conductive plate, which cools the supply air with no 1000-80,000 cubic feet per minute (CFM)56.
addition of humidity54.

52 
Fairconditioning, 2019. Evaporative Cooling. [Online] Available at: http://fairconditioning.org/knowledge/sustainable-cooling-technologies/evaporative-cooling/#1500552370074-
430ff37c-6e5440f0-dcf0
53 
Amer, O., Boukhanouf, R., & Ibrahim, H. G. A., 2015. A Review of Evaporative Cooling Technologies. International Journal of Environmental Science and Development, Volume
V6.571.
54 
Ibid.
55 
Ibid.
56
HMX, 2020. HMX-IEC. [Online] Available at: https://www.ategroup.com/hmx/product-family/product-description/hmx-iec-/

32 // Decoding Evaporative Air Coolers

IEC Applications:
IECs have various applications for effectively and efficiently providing thermal comfort to the occupants, specifically in large
commercial and industrial spaces, where an increase in humidity can cause probable harm to the setting or area in which IEC is
used. IECs supply 100% outdoor and cooled air with no added specific humidity. This helps maintain IAQ and provides thermal
comfort to the occupants57.
IECs can be effectively used in the following settings58:

Industries Pharmaceuticals Fast-moving Warehouses Factory sheds Large Residential

consumer goods commercial Apartments
(FMCG) industry areas

Figure 14: Applications of an IEC

2.2.3 | Indirect-Direct Evaporative Air Coolers

Structure:
An indirect-direct evaporative air cooler (IDEC) comprises a sensible HE, cooling
pad, blower fan, water tank, water distributor, pipe, and pump. The functions of these
components are the same as explained above in Sections 2.2.1 and 2.2.2.

Technology Description:
During the first stage,
An IDEC is also known as two-stage evaporative air cooler. During the first air is cooled through
stage, air is cooled through indirect evaporative cooling, followed by direct indirect evaporative
evaporative cooling in the second stage, as shown below in Figure 15. Air cooling, followed by direct
from secondary and primary air stream doesn’t come in direct contact. This evaporative cooling in the
technology, gives more cooling effect than IECs or DECs alone. The final second stage
cooled supply air has somewhat increased humidity. This technology is most
suitable for composite and hot-dry climates.

This technology is most

suitable for composite and
hot-dry climates.

Figure 15: Schematic of an IDEC 59

Ibid.
57 

58 
HMX, 2020. HMX-IEC. [Online] Available at: https://www.ategroup.com/hmx/product-family/product-description/hmx-iec-/
59 
Fairconditioning. Engineering Principle - Indirect-Direct Evaporative Cooling, Evaporative Cooling., Fairconditioning. Available at: http://fairconditioning.org/knowledge/
sustainable-cooling-technologies/evaporative-cooling/#1500296799628-e5546709-43d940f0-dcf0

Understanding Evaporative Air Coolers: Technology & Market Assessment // 33

 T: Dry-bulb temperature
W: Wet-bulb temperature

Working principle:

(Increases from bottom to top)

Specific Humidity, g/kg
3 W3
During First Stage: IEC
2 1
As shown above in Figure 11 and Figure 15, the warm air from the secondary
W1,W2 air stream is channeled through the wet air
stream panels in the sensible HE, where water is distributed. This leads to evaporation of water; air containing moisture
starts to exhaust out from the cooler, and the HE plates cool down due to heat transfer. Concurrently, the warm air from
the primary air stream is channeled through the dry air stream panels with cooled surfaces, in the HE, resulting in cooling
down of air due to heat transfer. Thus, cooled air with no added specific humidity is supplied to the second stage.
T3 T2 T1
During Second Stage: DEC
As shown above in Figure 15, the cooledDry-bulb
air with no added
Temperature, oC specific humidity from the indirect evaporative air cooler
(Increases from Left to Right)
system is channeled through the wet cooling pads. Here, cooled air comes in direct contact with water, evaporation
occurs with a change from sensible to latent heat, and the cooled air further cools down, with a little addition of
humidity. This cooled air with added moisture is then supplied via a blower to the room/space.
T: Dry-bulb temperature
W: Wet-bulb temperature
The psychrometric chart in Figure 16 shows that
during first stage, air moves towards its saturation

Specific Humidity, g/kg

temperature, i.e. from 1 to 2, as2 there is a reduction 1-2: First Stage
W2 2-3: Second Stage
in the dry and wet-bulb temperatures with no added T: Dry-bulb temperature
1
specific humidity in the primary supplied air. Then, W: Wet-bulb temperature
W1
in the second stage, direct evaporative cooling

(Increases from bottom to top)

Specific Humidity, g/kg
takes place, and the dry-bulb temperature of the 3
primary cooled air further reduces, but the wet-bulb W3

temperature remains the same (as shown in Figure W1,W2

2 1
16, from 2 to 3), with addition T2 of specific
T1 humidity.
Therefore, there is a reduction in enthalpy of air, due
Dry-bulb Temperature, oC
to presence of indirect evaporative cooling.

As the air coming into the DEC has already been T3 T2 T1

cooled, its water holding capacity is lower than that Dry-bulb Temperature,oC
of the secondary air stream. IDECs’ evaporation (Increases from Left to Right)

effectiveness ranges from ~90% to 115%, as there is

direct air-water contact, along with more cooled air
supplied outside with the same specific humidity61. Figure 16: Psychrometric Chart of an IDEC 60

IDECs’ evaporation effectiveness ranges from

~~90%
% toto 115%
%

60 
Amer, O., Boukhanouf, R., & Ibrahim, H. G. A., 2015. Two-stage IDEC system. Available at: https://www.researchgate.net/publication/265890843_A_Review_of_Evaporative_Cooling_
Technologies?enrichId=rgreq-6d19e6de5aa5b93ace10bbb7df1b0364-XXX&enrichSource=Y292ZXJQYWdlOzI2NTg5MDg0MztBUzoxNjUxOTgyMjg4OTM2OTdAMTQxNjM5NzczN
Tk5Nw%3D%3D&el=1_x_3&_esc=publicationCoverPdf
61
 mer, O., Boukhanouf, R., & Ibrahim, H. G. A., 2015. A Review of Evaporative Cooling Technologies. International Journal of Environmental Science and Development, Volume
A
V6.571.

34 // Decoding Evaporative Air Coolers

Performance Estimation
IDEC efficiency is based on the following62:

Type of heat Supply airflow Type of Secondary air Use of outside Climatic
exchanger through heat cooling pad or water flow air or exhaust of conditions
exchanger (both secondary air
DEC & IEC)

To calculate the maximum temperature drop possible, the following equation can be used63:
For IEC: DBFS (supply temperature) = DBA – [(DBA-WBA) X Heat Exchanger Efficiency]
For DEC: DBS= DBFS – [(DBFS-WBFS) X Direct Evaporative Efficiency]
Where:
A: Ambient air
S: Supply air of second stage (DEC)
DB: Dry-bulb temperature
WB: Wet-bulb temperature
FS: First stage (IEC)
DBA-WBA: Dry-bulb depression: the lowest temperature that can be achieved through 100% evaporation/ maximum
temperature drop that can be achieved through evaporation
IDECs are generally available in the Indian market in the range of 1,000-80,000 CFM and above64.

IDEC Applications:
IDECs have various applications in large-scale commercial and industrial spaces, where there is a significant pressure
drop requirement, but there is not much humidity or moisture content in the ambient air65.
Therefore, this technology is best suited for spaces such as those mentioned below66&67:

Residential Hotels Commercial Mall/Shopping Banquet/ Recreation/ Kitchens

Apartment Offices & Complex Function/ wellness
Buildings community halls centers/Gyms

Figure 17: Applications of an IDEC

62 
Fairconditioning, 2019. Evaporative Cooling. [Online] Available at: http://fairconditioning.org/knowledge/sustainable-cooling-technologies/evaporative-cooling/#1500552370074-430ff37c-
6e5440f0-dcf0
63
Ibid.
64
HMX, 2020. HMX-Ambiator. [Online] Available at: https://www.ategroup.com/hmx/product-family/product-description/hmx-ambiator/
65 
Ibid.
66 
Ibid.
67 
Fairconditioning, 2019. Evaporative Cooling. [Online] Available at: http://fairconditioning.org/knowledge/sustainable-cooling-technologies/evaporative-cooling/#1500552370074-
430ff37c-6e5440f0-dcf0

Understanding Evaporative Air Coolers: Technology & Market Assessment // 35

2.3 | Comparison of Evaporative Air Cooling
Technologies
The three primary types of evaporative air coolers can be compared based on their cooling medium, overall cooling
efficiency, application, operation and maintenance, and adaptability to climatic zones, as summarised below in Table 1.

Table 1: Comparison of Evaporative Air Cooling Technologies

Parameters DEC IEC IDEC

Capacity (approx.) 10-120 L68 1,000-80,000 CFM 1,000-80,000 CFM

Cooling medium Cooling pad Heat transfer through HE Combination of DEC & IEC

Efficiency More efficient than IEC Less efficient than DEC Most efficient

Specific Humidity content Yes No Yes, but less than DEC

in supplied air

Relation between enthalpy Dry-bulb temperature: Dry-bulb temperature: Decreases Dry-bulb temperature: Decreases
and dry and wet-bulb Decreases Wet-bulb temperature: Wet-bulb temperature: First reduces
temperatures Wet-bulb temperature: Decreases than remain constant
Constant Enthalpy: Decreases Enthalpy: Decreases
Enthalpy: No change

Operation and Easy in comparison to IEC& Medium in comparison to IDEC Difficult in comparison to IEC & DEC
maintenance IDEC & DEC

Applications (most Residential Large-scale commercial and Large-scale commercial and

optimal) industrial spaces where specific industrial spaces where there is
humidity in the supply air has to a significant temperature drop
be avoided requirement and the ambient air
has low humidity content

Adaptability with climatic Hot-dry Composite/Hot-dry Composite/Hot-dry

zones

Some manufacturers also manufacture hybrid/multi-stage evaporative air coolers, which can be a combination of
various versions of hybrid systems consisting of a DEC or IEC, or IDEC and a refrigeration system. In some cases, a
DEC combined with a refrigeration system or IDEC combined with refrigeration system. This type of device/system is
best suited for a warm and humid climate, where dehumidification is required.
The next section presents an overview of the market outlook for evaporative air coolers in India, including a summary
of the organised and unorganised market, major market players, distribution channels adopted by the different market
types, and the demand in residential and commercial markets.

This range is provided in litres, as DECs are mostly sold in the residential sector, and the range metric is defined taking into account the ease of understanding for the end-
68 

consumers.

36 // Decoding Evaporative Air Coolers

2.4 | Evaporative Air Cooler
Market in India

93%
Providing access to sustainable and affordable space cooling solutions
for all is one of the pressing needs in India. The vast majority of India’s
population—93% of residential consumers—lacks access to air conditioners
for attaining thermal comfort due to their high cost69. Furthermore, it is
anticipated that in the coming decade, a major share of households will of residential consumers—
still not have sufficient purchasing power for air conditioners70. With the lacks access to air
growing population, lack of access to cooling, limited purchasing power, conditioners for attaining
and India’s commitment to reduce its emissions by 2030, the evaporative thermal comfort due to
air cooler market seems to have promising growth potential. their high cost

As mentioned in Chapter 1, evaporative air coolers are much cheaper than

air conditioners and consume significantly less energy71&72. At present,
around 15% of Indian households are using evaporative air coolers73.
India’s evaporative air cooler market is projected to grow at a CAGR of
14.2% in 2019-25 and will achieve a market size of Indian Rupee (INR) 9000
crore by 202174&75.

15%
Currently, the organised evaporative air cooler market in India accounts
for 30% of the overall market, with the remainder captured by the
unorganised market76. Manufacturers supplying evaporative air coolers
in the unorganised sector usually target the market through offline
distribution channels and retail shops. In contrast, while the organised of Indian households
market is relatively smaller, it is driven by the bigger manufacturing are using evaporative air
companies, such as Symphony Limited, Bajaj Electricals Limited, Havels coolers
India Limited, Honeywell International Inc., Usha, Orient Electric Limited,
etc. These manufacturers target the market through both offline and online
distribution channels.

There are various kinds of evaporative air coolers available in the market
as per their application, placement, and the intended use; the different
types include wall-mounted coolers, personal coolers, window coolers,
tower coolers, outdoor coolers, etc., with low, medium, or high capacities.
The market is divided into residential and commercial by its application.
Preliminary stakeholder consultations conducted by AEEE indicated that the organised evaporative
DECs are largely in demand in the residential sector, and the demand air cooler market in India
for IDECs is expected to grow multi-fold in the commercial and industrial accounts for

30%
sector in coming years, due to their potential applications and low energy
consumption compared to air conditioners.

To facilitate the uptake of evaporative air coolers in the current market,

in addition to developing push and pull mechanisms for standardisation
of the overall market, with
and market transformation, it is important to understand the associated
the remainder captured by
institutional, policy, and regulatory framework. This framework is presented
the unorganised market
in the next chapter.

69
Ministry of Environment, Forest & Climate Change, 2019. India Cooling Action Plan, New Delhi: Ministry of Environment, Forest & Climate Change.
70 
Ibid.
71
 rand View Research, 2019. Air Coolers Market Size, Share & Trends Analysis Report By Type (Tower, Dessert), By Application (Residential, Commercial), By Region (North
G
America, Europe, APAC, CSA, MEA), And Segment Forecasts, 2019 - 2025, California: Grand View Research.
72
Jain, A., 2020. Bijli Bachao. [Online] Available at: https://www.bijlibachao.com/air-conditioners/best-air-cooler-india-brand.html [Accessed 2020].
73
 grawal, S., Mani, S., Aggarwal, D., Kumar, C.H., Ganesan, K., & Jain, A., 2020. Awareness and Adoption of Energy Efficiency in Indian Homes: Insights from the India Residential
A
Energy Survey (IRES) 2020, New Delhi: Council on Energy,Environment and Water.
74 
6Wresearch, 2019. India Air Cooler Market (2019-2025). [Online] Available at: https://www.6wresearch.com/industry-report/india-air-cooler-market-2019-
2025#:~:text=According%20to%206Wresearch%2C%20India%20Air,with%20the%20demonetization%20in%202016.
75
Research and Markets, 2015. India Air Cooler Market Outlook, 2021, India: Research and Markets.
76
Ministry of Environment, Forest & Climate Change, 2019. India Cooling Action Plan, New Delhi: Ministry of Environment, Forest & Climate Change.

Understanding Evaporative Air Coolers: Technology & Market Assessment // 37

3
Overview of National
Institutional, Policy, and
Regulatory Framework
This chapter examines the Indian institutional, policy
and, regulatory framework established to improve
overall appliance energy efficiency and quality. The
aim of the chapter is to help build an understanding
required for developing interlinkages to improve
evaporative air cooler performance.
3.1 | Institutional Framework for Appliances
The institutional framework for appliances in India is governed by various ministries, regulatory bodies, state agencies,
and associations, as shown below in Figure 18, in order to establish and implement the national level regulatory
framework. These organisations can impact the appliance standards & labelling programme, specifically for evaporative
air coolers. A summary of these organisations and their role in the appliance domain is provided below in Table 2.

Ministries Regulatory Bodies State Agencies Associations

• Ministry of Power (MoP) • Bureau of Energy •S
 tate Electricity • Indian Society of Heating,
Efficiency (BEE) Regulatory Commissions Refrigerating and Air
• Ministry of Commerce & (SERCs) Conditioning Engineers
Industry (MoCI) • Bureau of Indian (ISHRAE)
Standards (BIS) •S
 tate Designated
• Ministry of Environment, Agencies (SDAs) •C
 onsumer Electronics and
Forest & Climate Change • India Brand Equity Appliances Manufacturers
(MoEF&CC) Foundation (IBEF) Association (CEAMA)
• Ministry of Electronics & • Central Power Research
Information Technology Institute (CPRI)
(MeitY)
• Ministry of Consumer
Affairs, Food, and Public
Distribution

Figure 18: Indian Institutional Framework for Improving Appliance Energy Efficiency

Table 2: Role of Organisations in Indian Institutional Framework for Improving Appliance Energy Efficiency

S.No. Name Description Appliance-Related Role

1. Ministry The MoP focuses on policies, research, and the MoP has established the Bureau of Energy Efficiency
of Power development of India’s energy sector. The Energy (BEE), which has initiated and governs the standards
(MoP)77 Conservation Division under MoP is responsible and labelling programme for energy-intensive
for the formulation of energy conservation appliances.
policies, rules, & regulations under the Energy
Conservation (EC) Act, 2001.

2. Ministry of MoCI’s primary function is to develop, The Department for Promotion of Industry & Internal
Commerce implement, and monitor foreign trade policy to Trade under MoCI issues mandatory trademark
& Industry promote exports and imports. The ministry is also certificates under ‘The Trade Marks Act’ to the
(MoCI)78 responsible for areas related to special Economic manufacturers, which act as a license for conducting
Zones, multilateral and bilateral commercial commercial activities with consumer goods within the
relations, trade promotion and facilitation, Indian market. This trademark certificate is required
regulation of trade related commodities, and so for the manufacturers to seek permission from the
on. It has two primary sub-departments - the Bureau of Energy Efficiency (BEE) towards the usage of
Department of Commerce and Department for appliance star labels.
Promotion of Industry & Internal Trade. The
Department of Commerce has established a key
trust, India Brand Equity Foundation (IBEF).

77
Ministry of Power, 2020. Responsibilities. [Online] Available at: https://powermin.nic.in/en/content/responsibilities [Accessed 2020]
78 
Ministry of Commerce and Industry, 2020. Vision, Mission and Message. [Online] Available at: https://commerce.gov.in/ [Accessed 2020]

40 // Decoding Evaporative Air Coolers

 S.No. Name Description Appliance-Related Role
3. Ministry of MoEF&CC is responsible for the The Ozone Cell under MoEF&CC has published
Environment, implementation of policies and programmes ICAP in 2019, a flagship initiative. It is inclusive of a
Forest and related to natural resource conservation. long-term integrated 20 year (2017-18 to 2037-38)
Climate Change The ministry is also responsible for overall outlook across all sectors regarding India’s cooling
(MoEF&CC)79 environment protection, undertaking surveys demand, technology options, refrigerant use, and
and conservation of flora and fauna, pollution energy consumption. One of the ICAP objectives is
control & prevention, and animal welfare. to map alternative technologies that can cater to
There are various division under this ministry, the nation’s cooling requirement. It also sets a target
which are categorised under three main parts of 25-30% reduction in refrigerant demand. Most
i.e. environment division, establishment importantly, under the space cooling in buildings,
division and forest & wildlife division. ICAP recommends the development of MEPS for
evaporative air coolers.

4. Ministry of MeitY is responsible for policies related to MeitY issued the ‘Electronics and Information
Electronics & information technology (IT), electronics, and Technology Goods Order, 2012’, mandating Indian
Information the Internet, as well as the promotion of IT- Safety (IS) Standards on the notified goods listed
Technology related services. Its vision is to facilitate the under the ‘registration scheme’ issued by Bureau of
(MeitY)80 e-development of India. Indian Standards (BIS). This scheme was issued under
the BIS Act, 1986.
Under this scheme, manufacturers of the notified
products have to compulsory register under BIS
after testing their appliance/products in BIS-certified
test labs. Products that are not registered or do not
comply as per this scheme are not allowed to be sold
or exported.

5. Ministry of The Ministry of Consumer Affairs, Food, and The Department of Consumer Affairs was established
Consumer Public Distribution is further divided into two in June 1997. Its objective is to give a boost to the
Affairs, Food, departments: Department of Food and Public nascent consumer movement in India. BIS is a one
& Public Distribution and Department of Consumer of the divisions under the department of consumer
Distribution81&82 Affairs. affairs and this department was responsible for the
implementation of the Bureau of Indian Standards
Act, 2016.

6. Bureau BEE was established under the EC Act, 2001, BEE launched the Standard and Labelling (S&L)
of Energy with the mission to develop policies and programme in 2006 under Section 14 of the EC Act
Efficiency (BEE)83 strategies with a thrust on self-regulation. 2006. BEE has prepared a framework for assessing the
The major functions of the BEE include performance standards and rating criteria.
developing energy consumption and BEE defines the energy performance parameters for
process standards, MEPS & labels for various various equipment and appliances and assists in the
appliances, and specific EC building codes, programme’s implementation and enforcement via
identifying designated consumers, and creating awareness programmes, training, capacity building
awareness, along with dissemination of programmes, etc. The awareness programmes, along
information related to energy efficiency and with the energy efficiency labelling and standards,
conservation. help the consumer take a well-informed decision
before purchasing an appliance.

7. Bureau of Indian BIS’s primary responsibility is to ensure the BIS certification is one of the prerequisites for
Standards (BIS)84 standardisation and quality certification of any appliance to be covered/get registered under
goods. Its standardisation, certification, and the BEE’s S&L programme. The BIS has various
testing help provide credibility and assurance committees that are involved in setting safety
regarding the quality and safety of a product standards for appliances. BIS also carries out testing
for consumer usage. It also acts as a catalyst in laboratory certification across India, along with
promoting the import and export of goods. developing test standards as per local climatic
conditions.

79
Ministry of Environment, Forest and Climate Change, 2020. Introduction. [Online] Available at: http://moef.gov.in/about-the-ministry/introduction-8/
80
Ministry of Electronics & Information Technology, 2019. Vision & Mission. [Online] Available at: https://www.meity.gov.in/about-meity/vision-mission [Accessed 2020]
81
Department of Consumer Affairs, 2020. Vision and Mission. [Online] Available at: https://consumeraffairs.nic.in/vision-and-mission [Accessed 2020]
82 
Department of Food & Public Distribution, 2018. About Us. [Online] Available at: https://dfpd.gov.in/about-us.htm [Accessed 2020]
83
Bureau of Energy Efficiency, 2020. About BEE. [Online] Available at: https://beeindia.gov.in/content/about-bee [Accessed 2020]
84
Bureau of Indian Standards, 2020. About BIS. [Online] Available at: https://bis.gov.in/index.php/the-bureau/about-bis/ [Accessed 2020]

Overview of National Institutional, Policy, and Regulatory Framework // 41

 S.No. Name Description Appliance-Related Role
8. India Brand IBEF is a trust established to promote and IBEF is a well-established, credible trust, as it is the
Equity generate awareness on the Made in India label communication and branding partner for various
Foundation and India’s products & services in international trade exhibitions organised under the Department of
(IBEF)85 markets. IBEF’s three main pillars are export Commerce. IBEF provides the necessary support to
promotion, digital media, and knowledge manufacturers to enable them to access untapped
centre. It works closely with cross-sectoral market segments, along with monitoring the Indian
stakeholders on these topics. market’s production and sales volume.

9. Central Power As the centre for applied research in electrical CPRI is a member of the BEE Technical Committees for
Research power engineering, CPRI assists the electrical Appliance Labelling and provides necessary technical
Institute industry in product development and quality expertise regarding the development of performance
(CPRI)86 assurance. It also acts as an independent testing procedures and protocols. CPRI also carries out
authority for power equipment certification check-testing for selected products supplied by the
and testing. Bureau of Energy Efficiency and undertakes testing and
certification for manufacturers.

10. State Under the provisions of the Electricity Act, The SERCs are empowered by the EC Act to carry
Electricity 2003, SERCs were established with the forward the adjudication process after receiving
Regulatory objective to supervise and manage interstate non-compliance cases from SDAs. They appoint
Commissions electricity transmission, power-related disputes, Adjudicating Officers to conduct these inquiries.
(SERCs)87 electricity tariffs charged to consumers, etc.
SERCs are designated with the function of
setting the electricity tariffs and standards
in the electricity industry, advising decision
makers, and promoting competition, among
other things.

11. State SDAs were established as statutory bodies (as SDAs appoint an inspecting officer, as per the Energy
Designated per Section 15(d) of the EC Act 2001) in each Conservation (Inspection) Rules, 2010 and Section 17
Agencies state/by their respective state governments to of the EC Act, who ensures proper implementation and
(SDAs)88 enforce the EC Act. enforcement of the S&L scheme’s provisions and norms
for manufacturers. Any detected non-compliance is
reported to BEE.

12. Indian Society ISHRAE was formed with the objectives of Under appliances, ISHRAE is focused on developing the
of Heating, advancing the development of Heating, standards and regulations for refrigerant gases for BIS
Refrigerating Ventilation, and Air Conditioning (HVAC) and and BEE. Apart from this, it also organises the conclave
and Air refrigeration and related services, providing on HVAC and other services-related to industries. It
Conditioning knowledge to its members and other interested also provides a platform for showcasing innovations
Engineers actors in this domain, supporting students’ and facilitating buyer-seller connections. ISHRAE
(ISHRAE)89 career development, and fostering research in also has appliance-specific technical committees.
this field. Recently, a technical working group “F101 : Evaporative
Cooling systems” has been formed to foster research
opportunities to increase evaporative air cooler
performance.

13. Consumer CEAMA aims to enhance the development CEAMA has been working in the energy efficiency
Electronics of the consumer electronics and appliance domain, specifically in the star rating programme,
and industry and its components. Its objective is to implementation of waste of electronic equipment,
Appliances ensure fair competition among manufacturers, and digitisation of cable television networks. It is
Manufacturers dealers, and other stakeholders. involved in the manufacturing of televisions and home
Association appliances and catalyses the development of trade,
(CEAMA)90 entrepreneurship, technology, etc.

85 
India Brand Equity Foundation, 2020. About India Brand Equity Foundation. [Online] Available at: https://www.ibef.org/about-us.aspx [Accessed 2020]
86
Central Power Research Institute, 2020. About CPRI. [Online] Available at: https://www.cpri.in/about-cpri.html [Accessed 2020]
87
Bureau of Energy Efficiency, 2019. Enforcement Machinery under Energy Conservation Act, 2001, New Delhi: Bureau of Energy Efficiency
88
Ibid.
89 
Indian Society of Heating, Refrigerating and Air Conditioning Engineers, 2020. https://ishrae.in/Home/Aim_objectives. [Online] Available at: https://ishrae.in/Home/about_ishrae
[Accessed 2020]
90 
Consumer Electronics and Appliances Manufacturers Association, 2020. Association Overview. [Online] Available at: https://ceama.in/AssociationOverview.html [Accessed 2020]

42 // Decoding Evaporative Air Coolers

To understand the significance of the institutions mentioned above in Table 2, in light of improving evaporative air
cooler performance and energy efficiency, the next section will be elucidating about India’s policy, programmes, and
regulatory framework focused on improving appliance energy efficiency, with an emphasis on evaporative air coolers.

3.2 | Policy and Regulatory Framework Governing

Evaporative Air Cooler and Appliance Energy
Efficiency in India
This section provides an overview of the Indian standards for evaporative
air coolers established by Bureau of Indian Standards (BIS) and energy
efficiency programmes relevant for increasing appliance efficiency in India.

3.2.1 | Indian Standards for Evaporative Air Coolers 91

Bureau of Indian Standards’ (BIS) primary responsibility is standardisation and quality

certification of goods sold in India. It’s standardization, certification and testing
procedure help in establishing credibility and assurance over a good’s safety and
reliability for consumer usage. BIS introduced the Indian standard (IS) 3315 for testing
of evaporative air coolers in 1956, which was revised in 1974 and 1994 and reaffirmed
in 2005 and 2009. The latest version of the standard came out in 2019.
The 1974 version included a method to test the airflow rating. In 1994, power
consumption requirements, minimum cooling efficiency, the type of material to be
used (plastic was permitted), safety requirements, and test conditions were specified.
The latest IS 3315: 2019 revision incorporated noise level measurement protocol
and additional material specifications. The revisions made over the years are
summarised below in Figure 19.

•P ower consumption requirements

•M inimum cooling efficiency
• IS adhering material clause
•F
 irst version of IS for
•P ermission on using Plastic body
evaporative air coolers was
• Safety requirements
published
• Test conditions simplified

1956 1994
1974 2019
1st
• Equipment and Method • Noise levels measurement
to test air flow rating protocol
• Material specification

Figure 19: Evolution of the Indian Standard for Evaporative Air Cooler

Bureau of Indian Standards, 2019. Evaporative Air Coolers ( Desert Coolers ) — Specification (Third Revision). IS 3315: 2019. New Delhi: Bureau of Indian Standards.
91 

Overview of National Institutional, Policy, and Regulatory Framework // 43

MoEF&CC released a notification on 17th May, 1996 In addition, manufacturers have to show the consent
(GSR 214[E]) for incorporating eco-labelling, i.e. labelling clearance as per the provisions of the Water (Prevention
of environmentally-friendly products for evaporative air and Control of Pollution) Act, 1974, Water (Prevention
coolers, which is administered by BIS under the BIS Act, and Control of Pollution) Cess Act, 1977, and Air
2016. (Prevention and Control of Pollution) Act, 1981, along
with the authorisation, if required, under the Environment
Therefore, BIS has incorporated a few eco-labelling
(Protection) Act, 1986, if they are displaying Eco-mark
parameters such as noise level; quality, safety, and
on their evaporative air coolers.
performance-related requirements such as cooling
efficiency and power consumption; instructions for The latest IS 3315: 2019 standard is a comprehensive
proper use to maximise performance, safe disposal version, prepared by the Refrigeration and Air
of used appliances and reduced wastage; energy Conditioning Sectional Committee of BIS under the
consumption as per the set baseline; and use of Mechanical Engineering Division Council MED 03.
sustainable packaging. The Indian standard specifications for evaporative air
coolers are summarised below in Table 3.
Table 3: Key Specifications under IS 3315:2019 for Evaporative Air Coolers

S.No. Parameter Key Specifications

1. Air capacity • 750, 1000, 1260, 1500, 1800, 2000, 2500, 3000, 4000, 5000, 6000, and 8000 cubic meters (m3)/hour are
the specified air capacities based on the delivery of air at ‘zero’ static pressure.
• For any other capacity, there may be mutual consensus between the manufacturer and buyer.

2. Manufacturing I. Design and Build

and Outer Body Structure:
Construction • The thickness of the outer body structure shall be mentioned.
• Galvanised steel sheets conforming to IS 27792 shall be used for the outer structure.
• If a plastic body is used, it is mandatory for the manufacturer to mention its properties, such as
weathering, ageing, impact to the colour due to exposure to sun light, heat resistance, etc.
• Non-corrosive material shall be used for the grill, with an option to let air travel both horizontally and vertically.
• For the water tank, a sheet of minimum 1 millimetre (mm) thickness shall be used, and for the rest of the cabinet, a
sheet of nominal 0.8 mm thickness, with the tolerance as given in IS 277, shall be used.
• The capacity of the tank shall be as per Table 4.
Minimum Capacities (m3/h) (2) Sump Tank Capacity (litres) (3)
750 15
1000 20
1200 24
1500 30
1800 36
2000 40
2500 50
3000 60
4000 80
5000 100
6000 120
8000 160
Table 4: Water Tank Capacity Based on Minimum Air Capacity93
NOTE – Air coolers having minimum capacities up to 2000 m3/h shall be regarded as portable.
• The appliance shall pass the drop test.

II. Fan Specifications

• The fan material can be sheet metal or plastic.
• The fan shall pass IS 231294 testing protocols.
• The fan motor shall be IS 99695 certified.

III. The pump shall be IS 1195196 certified.

IV. Cooling pads

• Wood wool/honey comb or environmentally-friendly material shall be used.
• They shall be placed in wire mesh or plastic parts to avoid sagging.

92
Indian Standard: Galvanised steel sheets (plain and corrugated)-specification
93 
Bureau of Indian Standards, 2019. Evaporative Air Coolers ( Desert Coolers ) — Specification (Third Revision). IS 3315: 2019. New Delhi: Bureau of Indian Standards.
94
Indian Standard: Specification for Propeller Type ac Ventilating Fans
95
Indian Standard: Single Phase A.C. Induction Motors for General Purpose
96
Indian Standard: Pumpset for Desert Coolers - Specification

44 // Decoding Evaporative Air Coolers

 S.No. Parameter Key Specifications
3. Performance • Noise level: The appliance can pass the sound test as per IS 139197 (Part 2), and the decibel level
should not be more than 65 decibels (dBA), when measured at a 1 m distance from the cooler in
an anechoic (free from echo) room setting.
• The air delivery shall be as per the minimum air capacities mentioned in Table 5 and shall not be
less than the declared minimum capacity.
• The power consumption at zero static pressure shall be as mentioned below in Table 5.
Minimum Capacities m3/h (2) Max Power Consumption(w) (3)
750 95
1000 125
1200 150
1500 185
1800 210
2000 225
2500 240
3000 250
4000 280
5000 350
6000 400
8000 500
Table 5: Power Consumption of Evaporative Air Coolers Based on Air Capacity98
• Cooling effectiveness shall be either greater than or equal to 65 percent.

4. Tests • T he manufacturer needs to conduct both type and routine tests.

•A  routine test is a general test to be conducted by the manufacturer on every assembly and
includes the following production routine tests:
— General running
— Protection against electric shock
— High voltage
— Insulation resistance
— Current leakage
— Earthing connections
— Finish/Surface (corrosion and scratch-free)
— Power consumption test (shall not exceed the values specified in Table 5)
• T he type test includes:
— Verification of markings as specified in 7 of IS 302 (Part 1)99
— Cooling efficiency test
— Air delivery test
— Power consumption test
— All tests shall be as defined under IS 2312, except air delivery and power consumption tests
— Cooling efficiency and air delivery test (may be conducted at any ambient temperature)

More details about the BIS testing conditions for evaporative air coolers can be found in Annexure 1.

5. Rating • The rated voltage shall be in the range of 230-240 volts.

• A rated frequency of 50 Hertz (Hz) shall be maintained.

6. Additional Eco-mark • The evaporative air cooler shall conform to the safety, quality, and performance requirements as
requirements per the points mentioned above (points 2-5).
• The cooler shall be sold with proper usage instructions to maximise the performance, along with
biodegradable packaging.
• Noise levels shall conform to the norms specified in the Environment (Protection) Act, 1986.
• The power consumption shall be less than 5% of that specified in Table 5.

97 
Indian Standard: Room Air Conditioners — Specification Part 1 Unitary Air Conditioners
98
Bureau of Indian Standards, 2019. Evaporative Air Coolers (Desert Coolers) — Specification (Third Revision). IS 3315: 2019. New Delhi: Bureau of Indian Standards.
99
Indian Standard: Safety of household and similar electrical appliances, Part 1: General Requirements

Overview of National Institutional, Policy, and Regulatory Framework // 45

In addition to the above-mentioned key specifications, the Information on the electrical equipment, instrument
manufacturer shall provide an operating & maintenance accuracy, and measurement and calculation of airflow
manual. The manual shall cover the evaporative air temperature with an apparatus/instrument can be
cooler’s possible applications, i.e. which capacity of referred directly from the IS 3315: 2019.
evaporative air cooler is suitable for with which room Therefore, as per the latest BIS standard for evaporative
size. Furthermore, the standard also specifies that the air coolers, the air flow, outer structure material, noise
nameplate shall include the following information in a levels, and evaporative cooling pad, fan motor, and
location that is accessible and visible to the user: water pump efficiency are the most critical parameters
• Name of the manufacturer; for evaluating the overall cooling efficiency of an
• Type or model number, serial number, and year of evaporative air cooler. Evaporative air coolers adhering
manufacturing; to all the above-mentioned conditions may be given
• Minimum air capacity at zero static pressure; BIS standardisation, that is, the IS mark, under the
• Normal total current and voltage; provisions of the BIS Act, 2016. One parameter missing
• Power input; in this standard that affects overall evaporative air
• Sump tank capacity; and cooler performance is the water consumption level.
• Cooling efficiency of the unit. The next section presents all the programmes and
initiatives at the national level with emphasis towards
increasing appliance energy efficiency.

3.2.2 | Appliance Energy Efficiency Programmes in India

This section presents the national level programmes focused on enhancing appliance efficiency: BEE’s Standards and Labelling
(S&L) programme and National Mission for Enhanced Energy Efficiency (NMEEE).

3.2.2.1 | Standards and Labelling100

The S&L programme was established in May 2006 by energy-intensive appliances. In addition to MEPS,
BEE under the EC Act, 2001. The primary objective of this energy performance labels, as shown in Figure 20, are
programme is to provide clear information to the consumers affixed on appliances, providing a visual representation
about the energy savings potential of an appliance of the S&L programme. Establishing MEPS requires
through appliance-specific energy performance labels. either the establishment of an appliance’s performance
This allows the consumers to make informed decisions testing protocol, which aids in providing an estimate
when purchasing energy-efficient appliances. of the appliance’s performance, or a set cap/energy
The program focuses towards market transformation by performance target to be achieved.
maintaining energy consumption by MEPS for various

100
Bureau of Energy Efficiency, 2020. Standards & Labeling. [Online] Available at: https://beeindia.gov.in/content/standards-labeling

46 // Decoding Evaporative Air Coolers

BEE Energy Performance Label101&102
The BEE energy performance label, as shown in Figure 20, reflects an
appliance’s energy performance (e.g. for air conditioners, there is the Indian
Seasonal Energy Efficiency Ratio [ISEER]) and includes details such as the
appliance type, capacity, model-specific star label (1-5 stars), period of validity,
appliance brand and model, and electricity consumption.

BEE has classified the energy performance label into two categories
comparative label and endorsement label. The comparative label, as shown in
Figure 20, aids in the comparison of similar appliances based on their energy
consumption and other criteria. An endorsement label, on the other hand, as
shown in Figure 21, simply provides confirmation to the prospective buyer that
the product is highly energy-efficient and good for purchase/usage. Up until
now, only a few appliances, such as laptops and computers, have received an Figure 20: Star Label for Air
endorsement label. Conditioners: Comparative Label103

The energy performance labels range from 1-star to 5-star, 1 stands for minimum
efficiency/minimum energy performance level, is given to the least efficient
models and 5 for maximum efficiency, is given to the most efficient models.
The labels and minimum energy performance level are periodically upgraded
(approximately every 3-5 years) by BEE to maintain appropriate appliance
efficiency levels as per the technological development. Timely upgradation
ensures that very low-efficiency models are not supplied to the market.

Push & Pull Market Transformation Strategy105

The strategy of creating a ‘push’ & ‘pull’ in the appliance market to bring about
market transformation is the pillar behind the success of S&L programme’s Figure 21: BEE Endorsement Label104
success. The push for elimination of less energy-efficient models from the
market by prohibiting their sale is created through establishment of MEPS,
and a pull for consumers to opt for and purchase highly efficient appliances
or equipment is generated through the application of informative energy
performance labels for appliances. This mechanism enables standardisation of
the market, especially the unorganised appliance market sector, by mandating
manufacturers to manufacture and offer energy-efficient and standardised
appliances and equipment, along with regularly upgrading appliance
energy performance. In addition to the labels, governments and utilities also
offer rebates, tax incentives, on-bill financing schemes, high profile product The strategy of creating
demonstrations, and other modes of promotion of specific qualifying appliances a ‘push’ & ‘pull’ in the
such as Light Emitting Diodes (LEDs), Brushless Direct Current (BLDC) fans, and appliance market to
room air conditioners. bring about market
transformation is the pillar
Appliance Selection Criteria Under S&L Programme behind the success of S&L
The selection criteria followed by BEE for incorporation of an appliance or an programme’s success.
equipment into the S&L programme depends primarily on the appliance’s market
size, share of the organised & unorganised market, total energy consumption,
energy saving potential, ease in implementing the standard, availability of
appliance testing procedures, and test labs. Additionally, BEE also conducts its
own baseline estimation study to finalise the inclusion of a particular appliance
in the S&L programme. There has been a great emphasis on the test labs,
as these play a crucial role in determining whether the appliance meets the
set performance criteria through check testing and helps BEE develop realistic
efficiency performance standards, along with their timely upgradation.

101 
Bureau of Energy Efficiency, 2019. Impact of Energy Efficiency Measures for the Year 2017-18, New Delhi: Bureau of Energy Efficiency
102
Bureau of Energy Efficiency, 2020. Star Labelled Appliances. [Online] Available at: https://beeindia.gov.in/content/star-labelled-appliances
103
BEE star label for air conditioner notification
104
Bureau of Energy Efficiency, 2019. Impact of Energy Efficiency Measures for the Year 2017-18, New Delhi: Bureau of Energy Efficiency
105 
Bureau of Energy Efficiency, 2020. Lab Capacity Building. [Online] Available at: https://beeindia.gov.in/content/lab-capacity-building

Overview of National Institutional, Policy, and Regulatory Framework // 47

Mandatory and Voluntary Appliances
BEE has divided appliances in the S&L programme into two categories: mandatory and voluntary appliances. Currently,
BEE has established energy labels for 28 appliances, as mentioned below in Table 6, amongst which ten appliances fall
under the mandatory regime, and the remaining eighteen falls under the voluntary regime:

Table 6: BEE S&L Programme: Mandatory & Voluntary Appliances106

Mandatory Appliances Voluntary Appliances

1. Room Air Conditioners 11. Induction Motors

2. Frost Free Refrigerators 12. Pump Sets

3. Tubular Fluorescent Lamps 13. Ceiling Fans107

4. Distribution Transformers 14. Liquefied Petroleum Gas Stoves

5. Room Air Conditioners (Cassette, 15. Washing Machines

Floor Standing)

6. Direct Cool Refrigerators 16. Computers (Notebooks/Laptops)

7. Colour Televisions 17. Ballasts (Electronic/Magnetic)

8. Electric Geysers 18. O

 ffice Equipment (Printers, Copiers, Scanners, Multi-Function
Devices (MFDs)

9. Variable Capacity Inverter Air 19. Diesel Engine Driven Mono-set Pumps
Conditioners

10. LED Lamps 20. Solid State Inverters

21. Diesel Generator (DG) Sets

22. Chillers

23. Microwave Ovens

24. Solar Water Heaters

25. Light Commercial Air 27. UHD Televisions

Conditioners

26. Deep Freezers 28. Air Compressor

106
Bureau of Energy Efficiency, 2020. Standards & Labeling. [Online] Available at: https://beeindia.gov.in/content/standards-labeling
107 
S&L mandatory norms for ceiling fans were originally slated to be implemented from July 1, 2020. The implementation of new norms has been postponed to January 1, 2022.

48 // Decoding Evaporative Air Coolers

BEE runs the S&L programme with support from stakeholders such as manufacturers, Research & Development (R&D)
institutions, industry & industry association representatives, academia, consumer organisations, other government
organisations & regulatory bodies such as BIS, and other key private players. These stakeholders provide their holistic
input regarding standards and labels, and do their due diligence before the actual implementation of standards and labels.
For driving the S&L for each appliance, BEE establishes separate appliance-specific technical committees comprising of
key experts and stakeholders, which play a significant role in establishing and timely upgrading MEPS & labels for a
particular appliance, along with defining its implementation framework.

Permittee Guidelines
BEE has also established guidelines to be followed by permittees/manufacturers/organisations when registering their
appliances under the S&L programme, as summarised in Figure 22108.

Monitoring,
Company Model
Verification and Check testing
registration registration
Enforcement

Figure 22: S&L Registration Process

1. Company registration

Applicant/company has to register themselves on S&L web portal. A company has to register separately
for each different brand under an appliance type.

Submission of required documentation along with the application form: manufacturing area name and
address, quality management system certificate, BIS license, trade mark certificate, covering letter and
small scale industries (SSI) registration certificate.

Documentation to be submitted within the six months of the declaration.

100,000 INR has to be deposited at the time of registration as security deposit to BEE. SSIs have to pay
only 25000 for security deposit.

In case of registration for voluntary labelling program, an applicant is required to sign a non-judicial
stamp paper with BEE, showing their agreement towards the terms and conditions.

Once the company is registered, they can track the status of their application.

2. Model registration

After company’s/applicant’s registration, the model registration has to be done by depositing one-time
registration fees of 2000 INR/model along with required documents that are covering letter, proof of
payment through demand draft/online payment and test report from NABL accredited lab providing the
energy efficiency performance value.

In case manufacturer is providing in house test report then it should be submitted on organisation’s letter
head in the prescribed format and should not be old than a year.

The appliance should comply with the relevant standards as per the regulation.

The Independent Agency for Monitoring and Evaluation (IAME) will evaluate the application. After their
approval, BEE will allow the applicant to add BEE star label on the registered product.

Bureau of Energy Efficiency, 2016. Guidelines for the Permittee-Standards and Labelling program of BEE, New Delhi: Bureau of Energy Efficiency.
108 

Overview of National Institutional, Policy, and Regulatory Framework // 49

 3. Monitoring, Verification and Enforcement
Proper monitoring and verification, check and challenge testing of the labelled appliances will be
conducted by BEE or its designated agencies such as IAME and SDA to evaluate and verify whether the
energy performance of the labelled appliance under conditions mentioned in the appliance regulations
are matching its performance claims.

Check testing will be conducted in a third party NABL accredited laboratory.

If first check testing fails, second check testing will be carried out by BEE.

If the second testing also fails then the BEE provides two month time duration from the date of issuance of
intimation to the applicant to either change the star label level or remove the defects from the appliance
or remove all the appliance stock from the market.

An action taken report has to be submitted by the applicant.

If the report is not submitted within provided time frame or doesn’t comply with BEE’s directions then BEE
will withdraw the permission extended to the applicant for displaying star label on the appliance.

Challenge testing involves same steps as in check testing. It is done by BEE in a private lab when a written
complaint is received related to any fraud declaration on the star label of the appliance. Applicant has to
bear the cost of required testing, if fraud claims are affirmative.

Therefore, the cycle of any appliance under the S&L programme involves the following steps:

Selection of Technical Technical/ Launch of MEPS Enforcement Conversion

Appliance Committees Baseline Analysis (Voluntary)
• Market analysis: • Star level • Testing • Online portal • Monitoring & • Based on
market size, parameters standard's • Scrutiny of verification: market uptake
total energy •Star levels and baseline applications check of an appliance:
consumption, upgrades • Test data testing conversion
•A
 pproval/
energy saving collection • Penalty from voluntary
rejection for
potential, ease to mandatory
models
in implementing labelling
the standard, • Market analysis • Upgradation
& availability •Upgradation planning
of appliance planning
testing
procedures labs

Figure 23: Typical Cycle for an Appliance Under BEE's S&L Program

The next section sheds light on the National Mission for Enhanced Energy Efficiency (NMEEE) which is focused on improving
energy efficiency in energy-intensive industries. The section also elaborates on a sub-initiative-Super Efficient Equipment
Programme (SEEP) focused on bringing market transformation towards super-efficient appliances.

50 // Decoding Evaporative Air Coolers

3.2.2.2 | National Mission for Enhanced Energy Efficiency109,110&111
The NMEEE is one of the eight national missions under the National Action Plan on Climate Change (NAPCC) and focuses
on enhancing energy efficiency and reducing specific energy consumption (SEC), which is a major concern amongst
energy-intensive industries. The mission plans to raise the bar in its efforts to promote the energy efficiency market, which
has an estimated value of INR 74,000 crore and could help avoid capacity addition of 19,598 MW, achieve fuel savings
of around 23 million tonnes per year and greenhouse gas emissions reductions of 98.55 million tonnes per year at its
full implementation stage. The MoP and BEE were entrusted with the task of preparing the NMEEE implementation plan.
NMEEE consists of four initiatives with different focus areas, as described below:

• Perform, Achieve and Trade (PAT): A market-based mechanism to enhance the cost effectiveness of energy
efficiency improvements in energy-intensive large industries and facilities, through the certification of energy savings
that can potentially be traded112.

• Energy Efficiency Financing Platform (EEFP): Creation of mechanisms to help finance demand side management
programmes in all sectors by capturing future energy savings. Under this programme, Memorandums of
Understanding (MoUs) have been signed with financial institutions for collaborative work on the development of the
energy efficiency market and identification of issues related to this market development113.

• Framework for Energy Efficient Economic Development (FEEED): FEEED promotes energy efficiency through fiscal
instruments. Under this initiative, two funds have been created: Partial Risk Guarantee Fund for Energy Efficiency
(PRGFEE) and Venture Capital Fund for Energy Efficiency (VCFEE)114.

• Market Transformation for Energy Efficiency (MTEE): MTEE focuses on appliances. It was launched to promote the
usage of energy-efficient appliances in specific sectors through the development of innovative measures to make
the products more affordable. Under MTEE, two programmes have been developed: Bachat Lamp Yojana (BLY) and
Super Efficient Equipment Programme (SEEP)115.

BLY, a CFL replacement scheme, was launched in 2009 to promote energy-efficient lighting in India116. This scheme
was replaced by the Unnat Jyoti by Affordable LEDs for All (UJALA) scheme (LED replacement scheme), which was
launched by Prime Minister Narendra Modi on 1st May, 2015 under the joint initiative of Public Sector Undertaking
of the government of India (GoI), Energy Efficiency Services Limited (EESL) and the Electricity Distribution Company.
SEEP was launched in February 2012 to provide financial incentives to super-efficient appliance manufacturers in
the Indian appliance market, in order to enable total market transformation towards super-efficient appliances. The
first appliances that received support under this programme were ceiling fans, with an aim to incentivise and push
manufacturers to manufacture super-efficient 35 watt (W) ceiling fans with 50% more efficiency than the ones that
are currently available. Comprehensive support was provided to increase fan efficiency through the formation of a
multi-stakeholder technical committee to finalise the technical specifications and development of testing standards
for ceiling fans. After the launch of this programme, BLDC fans gained popularity, and various manufacturers have
started manufacturing BLDC fans, which are BEE 5 star-rated, i.e. the most efficient.117,118&119

To gain deeper understanding of the existing policy, regulatory, and institutional framework, the next section highlights
prevailing gaps and gives recommendations to address them in near future.

109
Bureau of Energy Efficiency, 2020. NMEEE. [Online] Available at: https://beeindia.gov.in/content/nmeee-1[Accessed 2020]
110 
Ministry of Power, 2020. Energy Efficiency. [Online] Available at: https://www.powermin.nic.in/en/content/energy-efficiency[Accessed 2020]
Bureau of Energy Efficiency, 2018. National Mission for Enhanced Energy Efficiency, New Delhi: Bureau of Energy Efficiency
111 

112
Bureau of Energy Efficiency, 2020. PAT. [Online] Available at: https://beeindia.gov.in/content/pat-3
113 
Bureau of Energy Efficiency, 2020. EEFP. [Online] Available at: https://beeindia.gov.in/content/eefp
114 
Bureau of Energy Efficiency, 2020. FEEED. [Online] Available at: https://beeindia.gov.in/content/feeed
115
Bureau of Energy Efficiency, 2020. MTEE. [Online] Available at: https://beeindia.gov.in/content/mtee-0
116 
Bureau of Energy Efficiency, 2020. BLY. [Online] Available at: https://beeindia.gov.in/content/bly-1
117 
Kanchwala, H., 2020. BLDC Fans (super efficient fans) in India 2020 - Market Analysis. [Online] Available at: https://www.bijlibachao.com/fans/bldc-fans-super-efficient-fans-in-
india-market-analysis.html
118
Bureau of Energy Efficiency, 2020. SEEP. [Online] Available at: https://beeindia.gov.in/content/seep-0
119 
Ministry of Power, 2020. Energy Efficiency. [Online] Available at: https://www.powermin.nic.in/en/content/energy-efficiency [Accessed 2020]

Overview of National Institutional, Policy, and Regulatory Framework // 51

3.3 | Gaps and Recommendations for the
National Institutional, Policy, and Regulatory
Framework Related to Evaporative Air
Cooler Performance
The gaps in the national policy, institutional, and regulatory framework discussed in this section, along with the
associated recommendations, have been identified based on the evaluation of above mentioned extensive literature
review and AEEE’s preliminary stakeholder consultations. The gaps are divided into the categories of policy and
regulatory, institutional level, and knowledge-related and are summarised in the following table.

Table 7: Gaps and Recommendations for the National Policy, Regulatory, and Institutional
Framework Related to Evaporative Air Coolers

Categories Gaps Recommendations

Policy and The IS for evaporative air The IS for evaporative air coolers should also focus on water consumption and its
regulatory coolers does not include efficiency level as a critical parameter, to cover the overall performance of evaporative
water efficiency as a air coolers.
parameter, even though IS
mentions eco-labelling for
evaporative air coolers.

Lack of concrete An in-depth market transformation potential study is required to identify the actual
research on the potential potential of evaporative air coolers in the commercial segment. SEEP for evaporative
of evaporative air air coolers could be proposed, with high growth potential in the Indian appliance
coolers and the market market.
transformation potential,
specifically for the
commercial sector.

Lack of testing standards Civil society organisations or any associations working in the field of appliance
or protocols for different efficiency could be appointed as knowledge-sharing bodies to support the S&L
types of evaporative air programme in framing energy efficiency performance testing standards for various
coolers. types of evaporative air coolers.

Institutional Lack of harmonisation BEE has technical bodies for defining and framing the S&L for a specific appliance,
level between governmental and BIS also has technical committees for individual appliance. In correspondence to
bodies, private entities, that, on a holistic level, there could be formation of an association that is either led by
autonomous bodies, and manufacturers, focusing primarily on manufacturers, or is formed by manufacturers,
industry associations as they are the key actors in the evaporative air cooler market.
working on improving
evaporative air cooler
energy performance.

Lack of focus on improving Manufacturers from both the organised and unorganised sectors could be encouraged
the unorganised market to come together and form a national association to work on improving evaporative
for this technology. air cooling technology. This association could work together in consensus with the
ongoing S&L programme, governmental bodies, and other key players by following
both the bottom-up and top-down approach.
Similarly, the S&L programme and BIS could also collaborate with this national
manufacturer association for the development, establishment, and upgradation of the
standards & labels for evaporative air coolers Hence, inter-body coordination could
be enhanced to enable better, fast-track establishment of MEPS for evaporative air
coolers in India.

52 // Decoding Evaporative Air Coolers

 Categories Gaps Recommendations
Knowledge- Unavailability of electricity In this era, where ‘the consumer is king’, customers should be provided information
related & water consumption and about the use of evaporative air coolers through an evidence-based approach, in
end-use appliance-specific order to increase evaporative air cooler adoption and usage. A mobile application
information for Indian could be developed that can be used in real time to capture and estimate various
households. required parameters, such as the ambient temperature and setting (indoor/outdoor);
while a customer is setting up an evaporative air cooler. This would help customer
in determining the potential cooling effectiveness of an evaporative air cooler. The
application would help customers in decision-making regarding evaporative air cooler
capacity and type, that they should install for achieving thermal comfort. Thus, it
could be an asset in awareness and evidence creation for both consumers and domain
experts/industry players.

Therefore, based on the evaluation of the above- international best practices focused on improving
mentioned comprehensive literature review and evaporative air cooler energy performance, in order
stakeholder consultations regarding India’s policy, to develop a more robust policy, regulatory, and
regulatory, and institutional framework, it is evident institutional framework for India’s evaporative air
that there is significant scope for improvement. Hence, cooler market. The following chapter presents these
there rises a need to look at and draw learnings from international best practices.

Overview of National Institutional, Policy, and Regulatory Framework // 53

4
Overview of International
Institutional, Policy, and
Regulatory Framework on
Evaporative Air Coolers
This chapter presents key findings from the detailed
review of international MEPS, testing standards, and
regulations on evaporative air coolers. In addition,
it also highlights the key findings from the review
of ASHRAE’s testing standards for DECs and IECs,
along with the initiatives taken by international
organisations to improve evaporative air cooler
performance.
4.1 | Country-Wise Evaporative Air Cooler Standards
Australia, USA (California), and Iran have been identified for the review of their institutional, policy and, regulatory
framework developed to enhance evaporative air cooler performance. The criteria for selecting these three countries
was based on their similar climatic conditions to India and the availability of information on the MEPS/testing standards/
regulations for evaporative air coolers. Table 8 provides an overview of the information about the selected countries
on the basis of type and status of MEPS/testing standards/regulations for evaporative air coolers, implementing
organisations, and target sectors of application.

Table 8: Global Institutional, Policy and Regulatory & Framework for Evaporative Air Coolers

Country Implementing Product Standards Target Mandatory/ Policy Revision Update

Organisation & Labelling/ Sector Voluntery Adoption Date (if any) Status
Testing Date

Australia120 Standards Evaporative Energy Information Information 1987 2000 and Up to

Australia air cooler performance not not reconfirmed date
Committee ME-62, testing available available in 2016
Ventilation and Air standard
conditioning

USA California Evaporative Appliance Information Information 1976 2016 Up to

(California) Energy air cooler efficiency not not date
121&122
Commission regulations available available

Iran123&124 Institute of Heating & Air Comparative Residential Mandatory 1999 2009 Under
Standards and Conditioning, Label & MEPS revision
Industrial Research Evaporative
of Iran (ISIRI) Cooler

4.1.1 | Australia 125&126

Australia has a tropical climate, and the majority of its cooling demand
is for DECs. Australia has established the AS/NZS 2913-2000 testing
standards for evaporative air-conditioning equipment. The standards
have been prepared by the Standards Australia Committee ME-062,
Ventilation and Air Conditioning, Manufacturing & Processing under
Standards Australia, which is an independent, non-governmental
standard setting organisation. Australia does not have MEPS or labelling
for evaporative air coolers 127.
The first version of this testing standard came in 1987, and it was then
revised in 2000 and reconfirmed in 2016. The standard focuses upon the
following parameters 128:
• Airflow
• Evaporation efficiency 129
• Sound power measurements
• Power consumption
• Operating conditions

120
Standards Australia, 2016. Australian Standard Evaporative airconditioning equipment, Strathfield, NSW 2135: Standards Australia International Ltd.
121 
California Energy Commission, 2017. 2016 Appliance Efficiency Regulations. California Energy Commission. CEC-410-2017-002
122 
Richter, C., Chase, A., Marver, J., Cunningham, K., Wilkins, B., and McLain, L., 2016. Developing an Appliance Standards Compliance Improvement Program. Pacific Grove, ACEEE
Summer Study on Energy Efficiency in Buildings.
123
CLASP, 2020. Policy Details. [Online] Available at: https://clasp.ngo/policies/iran-meps11[Accessed 2020]
124 
Effatnejad, R. and Salehian, A.B., 2009. Standard of energy consumption and energy labeling in evaporative air cooler in Iran. Jurnal IJTPE, 1.
125 
Saman, W., Bruno, F., & Tay, S., 2010. Technical Research on Evaporative Air Conditioners and Feasibility of Rating their Energy Performance: Institute for Sustainable Systems and
Technologies
126
Standards Australia, 2016. Australian Standard Evaporative airconditioning equipment, Strathfield, NSW 2135: Standards Australia International Ltd.
127 
Ibid.
128 
Ibid.
129
 vaporation effectiveness/efficiency: 100 x [(inlet air dry-bulb temperature (°C) - outlet air dry-bulb temperature (°C)) / inlet air dry-bulb temperature (°C) - inlet air wet-bulb
E
temperature (°C)]

56 // Decoding Evaporative Air Coolers

It specifies temperature conditions required for evaluating and rating the
cooling performance, with inlet dry and wet-bulb temperatures of 38°C and
21°C, respectively, and a supply dry-bulb temperature of 27.4°C. However,
energy ratings are not mentioned. For the abovementioned parameters, the
standard provides a rating, testing protocols, and instruments/equipment
verified for rating evaporative air coolers. It also focuses on construction
requirements. This standard does not cover information related to IEC or
IDEC indirect or two-stage evaporative air coolers, and there is no focus
on evaluating water consumption. 130&131

Apart from this, the Australian government, states, and territories and
the New Zealand government collaborated to develop an integrated
programme called the Equipment Energy Efficiency Programme (E3 WELS and DMITRE have
Programme), which includes MEPS and energy rating labels for equipment conducted a study that
and appliances used by households and businesses in Australia and New recommended focusing
Zealand. The Energy Rating Label under the E3 programme is specifically on developing and
for air conditioners (single phase, non-ducted), washing machines and introducing water and
dryers, dishwashers, televisions, refrigerators, freezers, and computer energy performance labels
monitors. Greenhouse and Energy Minimum Standards (GEMS), which for evaporative air coolers.
was introduced for creating a national framework for product energy
efficiency in Australia, is the foundation for the E3 programme. Under the
E3 programme, educational and training activities are also undertaken
to help consumers with their purchase decisions of opting for an energy-
efficient appliances. This includes interactions with retailers and traders
who are in direct contact with the consumers.132&133

Australia has a separate Water Efficiency Labelling and Standards (WELS) programme under the Department of the
Environment, Water, Heritage, and the Arts for taps, showers, dishwashers, washing machines, lavatory equipment,
urinals, and flow controllers134. In 2009, the WELS, Australian Ministerial Council on Energy, and Department
of Manufacturing, Innovation, Trade, Resources, and Energy (DMITRE) of Australia conducted a scoping study
that concluded that evaporative air coolers should become the part of WELS scheme for overall water efficiency
improvement and recommended an integrated approach that the labelling for both water and energy performance
should be introduced together, in order to avoid any negative impact, such as increased peak demand or creation
of less favorable market conditions for evaporative air coolers than air conditioners135. As per this study, the potential
integrated label and testing methodology should focus upon various aspects of water efficiency, such as water bled-
off rate, type of water bleeding/drain-off system, water consumption at different speeds, overall water quality (such as
salinity level,) and various aspects of energy performance such as wet and dry-bulb temperatures, airflow rate, power
consumption by the fan, pump, and control/remote systems, and pressure drop across the cooling system. Apart from
this, the report also states that the evaporation rate, water bled-off rate, type of cooling pads and total dissolved salts
(TDS) level, are other important parameters to consider in assessing the water consumption by an evaporative air
cooler.136&137

Based on the review of Australian standards and ongoing studies and initiatives, it has been observed that currently
they have not yet covered water efficiency as a parameter for testing evaporative air cooler efficiency. However,
WELS and DMITRE have conducted a study that recommended focusing on developing and introducing water and
energy performance labels for evaporative air coolers.

130 
Saman, W., Bruno, F., & Tay, S., 2010. Technical Research on Evaporative Air Conditioners and Feasibility of Rating their Energy Performance: Institute for Sustainable Systems and
Technologies
Saman, W., Bruno, F., & Liu, M., 2009. Technical background research on evaporative air conditioners and feasibility of rating their water consumption: Institute for Sustainable
131 

Systems and Technologies

132 
Energy Rating, 2020. ABOUT THE E3 PROGRAM. [Online] Available at: https://www.energyrating.gov.au/about-e3-program [Accessed 2020].
133 
Australian Government, 2020. Energy rating label. [Online] Available at: https://www.energy.gov.au/rebates/energy-rating-label [Accessed 2020].
134 
Australian Government, 2017. Inspections and enforcement. [Online] Available at: https://www.waterrating.gov.au/enforce [Accessed 2020].
135 
Saman, W., Bruno, F., & Liu, M., 2009. Technical background research on evaporative air conditioners and feasibility of rating their water consumption: Institute for Sustainable
Systems and Technologies
136
Ibid.
137 
Saman, W., Bruno, F., & Tay, S., 2010. Technical Research on Evaporative Air Conditioners and Feasibility of Rating their Energy Performance: Institute for Sustainable Systems and
Technologies

Overview of International Institutional, Policy, and Regulatory Framework on Evaporative Air Coolers // 57
4.1.2 | USA (California) 138

California majorly has a Mediterranean climate, with hot and dry summers,
making the use of evaporative air coolers feasible for achieving thermal
comfort. The California Energy Commission established appliance
efficiency regulations (California Code of Regulations, Title 20) in 1976. The
latest version of this regulation, ‘CEC-410-2017-002’, dated January 2016,
includes a process for evaluating and rating evaporative air cooler energy
performance. These regulations were approved by the California Office of
Administrative Law on December 31, 2016 139.

Government State
Level California Natural Sub-
commission California Sub-
Division Efficiency
of California Resources Energy Division
Agency (CNRA) Commission

Figure 24: Institutional Framework for Appliance Efficiency in California

The California Energy Commission (former Energy Currently, twenty-one appliance categories are
Resources Conservation and Development covered in this appliance efficiency regulation,
Commission) was formed in 1974. It comes under the including evaporative air coolers. The Evaporative
California Natural Resources Agency (CNRA), a state Cooler Efficiency Ratio (ECER) is used as a parameter
cabinet-level agency in the Californian government, to evaluate energy performance and evaporation
and is the state’s primary energy policy and planning efficiency and is calculated using the following
agency. One of the primary functions of this commission equation142:
is to develop, implement, and enforce California’s
ECER = 1.08 (troom - (tdb-E x (tdb-twb))) x Q/W
Appliance Energy Efficiency Standards and Labels.
One of its sub-divisions, the Efficiency Division, is Where:
responsible for developing and implementing cost- troom = room dry-bulb temperature, oF
effective appliance standards to save energy and tdb= outdoor dry-bulb temperature, oF
provide thermal comfort.140&141 twb = outdoor wet-bulb temperature, oF
E = saturation effectiveness/100
Q = airflow rate, CFM
W = total power, W

The specified conditions for calculating ECER include inlet dry- and wet-bulb temperatures of 32.8 and 20.6°C, respectively,
and an assumed room outlet air temperature of 26.7°C143. These temperature conditions should be used in oF, while
calculating the ECER. The regulation focuses on airflow, Evaporative Media Saturation Effectiveness (%) for DEC, Media
Type (for DEC) and Cooling Effectiveness (for IEC), Total Power (W), and Airflow Rate (CFM). The regulation take into account
ASHRAE’s testing standard for both direct and indirect evaporative air coolers144.
Based on the review of California’s appliance efficiency regulations, California, like Australia, has not focused on including
water consumption as a performance and efficiency assessment parameter for evaporative air coolers. The most important
parameter they have used to evaluate performance is the ECER. The regulation only specify the testing methods for
evaporative air coolers and haven’t included their MEPS.

138
California Energy Commission, 2017. 2016 Appliance Efficiency Regulations. California Energy Commission. CEC-410-2017-002
139 
Ibid.
140 
California Energy Comission, 2020. About. [Online] Available at: https://www.energy.ca.gov/about#:~:text=The%20Warren%E2%80%90Alquist%20Act%20established,and%20
reliable%20supply%20of%20energy. [Accessed 2020].
141
California Energy Comission, 2019. Efficiency Division. [Online] Available at: https://www.energy.ca.gov/about/divisions-and-offices/efficiency-division [Accessed 2020]
142 
Saman, W., Bruno, F., & Tay, S., 2010. Technical Research on Evaporative Air Conditioners and Feasibility of Rating their Energy Performance: Institute for Sustainable Systems and
Technologies
143 
Saman, W., Bruno, F., & Liu, M., 2009. Technical background research on evaporative air conditioners and feasibility of rating their water consumption: Institute for Sustainable
Systems and Technologies
144
California Energy Commission, 2017. 2016 Appliance Efficiency Regulations. California Energy Commission. CEC-410-2017-002

58 // Decoding Evaporative Air Coolers

4.1.3 | Iran 145&146

Iran largely has a dry climate and a high demand for evaporative air coolers.
The Institute of Standards and Industrial Research of Iran (ISIRI) established the
mandatory comparative labelling programme 4910-2 for evaporative air coolers
in 1999 under the Energy Efficiency Labelling of Energy Consuming Products,
which was revised in 2009147&148. The aim of this mandatory labelling programme
is to encourage manufacturers to produce energy-efficient coolers complying
with the standard performance criteria.
ISIRI is the official government body responsible for developing and implementing
standards in Iran and operates under the supervision of the Ministry of Industry,
Mines, and Trade, Islamic Republic of Iran. It has also established energy labels
and MEPS for refrigerators, refrigerator-freezers, and hermetic compressors149.

Islamic Republic of Iran

Ministry of Industry, MInes and Trade Ministry of Energy

Institute of Standards and Industrial Research of Iran Renewable Energy and Energy Efficiency
(ISIRI) Organization (SATBA)

Figure 25: Institutional Framework for Appliance Efficiency in Iran

ISIRI is also an active member of the International Organisation for

Standardisation (ISO) technical committees. ISIRI is working with the Iranian
Ministry of Energy’s Renewable Energy and Energy Efficiency Organisation
(SATBA) to produce periodic reports on the energy rating of equipment
which are subjected to mandatory compliance with standards. The aim of
this collaboration is to increase consumer awareness on appliance power
consumption150.
During the pre-label design stage for evaporative air coolers, consultations
with manufacturers were done to assess the key factors affecting evaporative
air cooler energy consumption. The key parameters identified were the
following151:
• Fan and motor efficiency
• Evaporative cooling pad density
• Rate of water circulation
In Figure 26, the label shows efficiency grades from 1, denoted as A (most
efficient - the shortest bar, which is green), down to 7, denoted as G (least
efficient - the longest bar, which is red). Manufacturers who find this label to
be an effective marketing tool are promoting it.
Figure 26: Iranian Energy Label152

145
 aman, W., Bruno, F., & Tay, S., 2010. Technical Research on Evaporative Air Conditioners and Feasibility of Rating their Energy Performance: Institute for Sustainable Systems and
S
Technologies
146 
Effatnejad, R. and Salehian, A.B., 2009. Standard of energy consumption and energy labeling in evaporative air cooler in Iran. Jurnal IJTPE, 1.
147 
Ibid.
148
CLASP, 2020. Policy Details. [Online] Available at: https://clasp.ngo/policies/iran-meps11[Accessed 2020].
149 
Institute of Standards & Industrial Research of Iran, 2020. Introduction. [Online] Available at: http://www.isiri.com/about.htm [Accessed 2020].
150 
Ibid.
151
 aman, W., Bruno, F., & Tay, S., 2010. Technical Research on Evaporative Air Conditioners and Feasibility of Rating their Energy Performance: Institute for Sustainable Systems and
S
Technologies
152
Effatnejad, R. and Salehian, A.B., 2009. Standard of energy consumption and energy labeling in evaporative air cooler in Iran. Jurnal IJTPE, 1.

Overview of International Institutional, Policy, and Regulatory Framework on Evaporative Air Coolers // 59
 The Energy Efficiency Ratio (EER) is used as an energy labelling parameter
Rating EER Value to compare products, as shown in Figure 27. EER is the ratio of the sensible
1 EER>_65 cooling capacity of air power (kW) to the total input power (kW).

2 58<_EER<_65 qs- Q.ρ.Cp.(tdo- tdi)

EER =
Pt
3 50<_EER<_58

4 42<_EER<_50 Where:
qs: sensible cooling capacity kW times
5 34<_EER<_42 Pt: power consumption kW cooler times
6 26<_EER<_34 Q: air flow cubic meter per hour or cubic foot per minute
ρ: air density according kg per square meter
7 EER<26
Cp: specific heat of air at constant pressure, kJ.kg Kelvin times
Figure 27: Energy Efficiency tdo: dry air output temperature according to degrees Celsius
Thresholds for Iranian Energy Label153 tdi: dry air temperature input according to degrees Celsius

The sensible cooling capacity of the evaporative air cooler can be

defined as:
qs = Q ρ Cp (tdi − tdo )

The evaporative air cooler’s cooling capacity is dependent on the evaporation effectiveness, inlet air’s dry and wet-
bulb temperatures, and airflow rate. If the value of cooling capacity is positive, this indicates that cooling has been
achieved. Iran had to develop its own testing protocols, as it was the first country to develop and implement MEPS
& labelling for evaporative air coolers. The testing is as per Iranian test standards No. 4910 and No. 4911, which
use the Australia Standard 2913-2000 and BIS standards as their base test standards. There is no focus on water
consumption154.
In terms of unique features, Iran is the only county that has a set MEPS and mandatory comparative labelling programme
for evaporative air coolers. Iran’s label uses a star rating to define the most and least efficient evaporative air coolers
and EER as an energy labelling parameter to compare various evaporative air cooler models. In order to increase
consumer awareness on appliance power consumption, ISIRI, SATBA, and the Iranian Ministry of Energy work together
to develop periodic reports on equipment energy rating, which are subjected to mandatory enforcement of standards.
Table 9 below summarises the temperature conditions specified for evaporative air cooler rating in the select countries.

Table 9: Rating Temperatures (°C) of the Select Countries

Rating Temperature (°C) Australia (AS/NZS 2913-2000) California (California Code of Iran Appliance Label & MEPS
Regulations, Title 20)

Outdoor Dry-Bulb 38 32.8

Temperature

Outdoor Wet-Bulb 21 20.6

Information Not Available
Temperature

Indoor Dry-Bulb 27.4 26.7

Temperature

It was observed that none of the countries have taken into consideration water consumption as an element for
improving overall evaporative air cooler performance.
The following section examines ASHRAE’s testing standards for evaporative air coolers.

153
 aman, W., Bruno, F., & Tay, S., 2010. Technical Research on Evaporative Air Conditioners and Feasibility of Rating their Energy Performance: Institute for Sustainable Systems and
S
Technologies
154 
Saman, W., Bruno, F., & Liu, M., 2009. Technical background research on evaporative air conditioners and feasibility of rating their water consumption: Institute for Sustainable
Systems and Technologies

60 // Decoding Evaporative Air Coolers

4.2 | International Testing Standards
This section highlights the key findings from the review of ASHRAE’s testing standards for direct and indirect evaporative
air coolers.

4.2.1 | ASHRAE Standard 133-2015: DEC Testing Method 155

ASHRAE has established Standard 133, the international standard for DECs, which includes the lab testing procedures
for calculating the overall cooling effectiveness of a DECs, in order to obtain related ratings.
The first version of this standard was issued in 2001, followed by a revised version in 2008, and the latest version came
out in 2015. The first version provided the testing procedures for DECs under laboratory conditions to obtain a specific
rating. In 2008, the test standards were modified, with a condition added to the testing procedures, namely, that no other
sources of heat transfer shall be present during testing.
In the 2015 version, it was clarified that the density correction to saturation effectiveness shall be treated as a function
of the actual airflow test standard. It covers the testing method for measuring the saturation effectiveness, air and water
flow, and total power of packaged156 and component157 evaporative air coolers. The standards also focus on fan rotation
speed and density of the air. The target users defined for this standard are evaporative air cooler end-consumers in
residential, industrial/commercial, and agricultural settings. Figure 28 displays the key parameters for DEC testing as
per the latest version of this standard.

Testing Requirements Report & test results

• Determination/Measurement/Reading frequency • Perofrmance data and curve
• Equilibrium condition • Method of supplying water
• Air flow rates • Information related to test, model and person who
• Humidity & temperature condition conducted the test
• Water quality standard and conductivity
• Water entrainmnet

Figure 28: Key Parameters Under ASHRAE Standard 133-2015 for DECs

155
 NSI/ASHRAE Standard 133-2015, 2015, Method of Testing Direct Evaporative Coolers, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.,
A
Atlanta.
156 
A self-contained unit, inclusive of a fan and fan motor, whose primary functions are (a) the conversion of the sensible heat to latent heat through the process of evaporating
the recirculating or nonrecirculating water directly exposed to this air and (b) the movement of this air through the unit.
157 
A self-contained cabinet without a fan whose primary functions are (a) the conversion of the sensible heat to latent heat through the process of evaporating the recirculating
or nonrecirculating water directly exposed to this air and (b) the movement of this air through the cabinet, which allows a portion of this water to evaporate.

Overview of International Institutional, Policy, and Regulatory Framework on Evaporative Air Coolers // 61
Following are the key highlights of this standard:
• The airflow rate at which two different static pressure differential
points or the bi-stable performance points can be measured shall
be recorded. These points could be set to reduce or increase the
airflow rate.
— Standard water quality to be maintained with the conductivity
meter with an accuracy of ±10% of observed reading shall be
used to measure water’s conductivity and for entrainment
verification, the air testing equipment shall be kept safe from
water entrainment, to avoid alteration in temperature readings.
• The acceptable temperature and humidity test conditions include
the following:
Table 10: The Acceptable Temperature and Humidity Test Conditions
under ASHRAE Standard 133-2015

Type of Temperature Specified Temperature

Inlet air dry-bulb temperature: maximum 46°C (115°F)

Wet-bulb temperature: minimum 5°C (41°F)

Wet-bulb depression: minimum 11°C (20°F)

• The following parameters need to be calculated from the test data:

— Standard airflow rate
— Standard static pressure differential
— Standard fan power
— Standard power input
— If the rotation speed varies from one reading to another, a
correction will be required in the value calculated under the test
conditions to convert it into a nominal fan speed at standard
density.
— The saturation effectiveness shall be called as the function
airflow rate corrected to standard air
• The final lab test report on an evaporative air cooler shall include
details about the object, results, test set-up, instruments for testing,
test data on the evaporative cooler/cooling unit, and name of the
test lab.
ASHRAE testing standard 133-2015’s DEC testing method focuses
on saturation effectiveness, dry and wet-bulb temperatures, air
and water flow, the total power of the packaged and component
evaporative air cooler, fan rotation speed, density of the air, static
pressure, water quality, and water entrainment. Details on the
requirements for testing, instruments, and methods of measurement,
instructions for recording data, and information to be included in the
report & test results can be found in Annexure 2. The information
on the equipment and its set-up, along with the calculation of key
parameters—i.e. air density & velocity, power input, airflow rate,
saturation effectiveness, static pressure differential, and calibration
corrections—can be obtained directly from the ASHRAE testing
standard 133-2015.

62 // Decoding Evaporative Air Coolers

4.2.2 | ASHRAE Standard 143-2015: IEC Testing Method 158

ASHRAE has established the standard 143, an international standard for IECs that includes the lab testing procedures for
calculating an IEC’s cooling effectiveness and power requirement in order to obtain related ratings. Compliance with this
standard is voluntary. The first version of this standard was approved in 2000, and the latest revision came out in 2015.
This standard is designed to estimate key parameters such as airflow and temperature (inlet and outlet) to calculate the
pressure drop to achieve evaporative air cooling. Figure 29 displays the key parameters for IEC testing as per the latest
version of this standard.

Sub categories Testing Requirements Report & test results

• C omponent indirect evaporative • Airflow rates • Performance curves
coolers • Temperature difference • D ata realted to barometric
• S emi-packaged secondary indirect • Measurement/reading frequency pressure, primary and secondary
evaporative coolers air temperature, primary and
• S emi-packaged primary indirect secondary air flow rate, electric
power input, and primary and
evaporative coolers
secondary air static pressure drop
• P ackaged indirect evaporative • Information related to model, test
coolers
and person who conducted the
test

Figure 29: Key Parameters Under ASHRAE Standard 143-2015 for IEC

Following are the key highlights of this standard:

• Under this testing standard, the IECs are sub-divided into the following four categories, as per their construction style:
component IECs, semi-packaged secondary IECs, semi-packaged primary IECs, and packaged IECs. Details about
these sub-categories are provided in Annexure 3.
• The final lab test report on an evaporative air cooler shall include details about the object, results, test set-up,
appurtenances, testing instruments, and test data. It shall also provide information such as the IEC type, information on
the specific evaporative air cooler model as per the manufacturer, test identification number, test lab, date of testing,
and name of the person who conducted the test.
• The test report shall include data on the barometric pressure, primary and secondary air temperature, primary and
secondary air flow rate, electric power input, and primary and secondary air static pressure drop.
• Performance curves of the electricity inputs and cooling capacity shall be included. In the case of IECs that do not have
air-moving devices, their static pressure drop curves shall also be included.

ASHRAE testing standard 143-2015’s IEC testing method focuses on the cooling effectiveness, power requirement, dry
and wet-bulb temperatures, airflow, temperature (inlet and outlet), static pressure drop, and barometric pressure. Details
on the requirements for testing, instruments, apparatus, testing methods, and test reports are provided in Annexure 3. The
information on the compliance and calculation of key parameters—i.e. air density & velocity, total power input, airflow
rate, cooling effectiveness, cooling capacity, and calibration corrections—can be refereed directly from the ASHRAE
testing standard 143-2015.
Overall, ASHRAE’s testing standards for direct and indirect evaporative air coolers cover the dry and wet-bulb
temperature, airflow rate, water flow, power requirement, saturation effectiveness, water quality, water entrainment, and
static pressure. They do not include testing of the type of material used in the outer structure, noise levels, or evaporative
cooling pad effectiveness, which are also critical parameters for testing and evaluating evaporative air cooler’s overall
cooling efficiency.
The next section presents the initiatives taken up by international organisations to increase evaporative air cooler
performance and energy efficiency.

158
 NSI/ASHRAE Standard 143-2015, 2015, Method of Test for Rating Indirect Evaporative Coolers, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.,
A
Atlanta.

Overview of International Institutional, Policy, and Regulatory Framework on Evaporative Air Coolers // 63
4.3 | International Initiatives
This section will elucidate about the key findings from the review of voluntary rating standards for evaporative air coolers
introduced by Eurovent Certita Certification (ECC).

4.3.1 | Eurovent Certita Certification’s Rating Standard for Evaporative Air Coolers 159

Eurovent Certita Certification (ECC) is an international private organisation founded in 1993 that has gained international
recognition as a third-party product performance certification body for HVAC and refrigeration products. It is an accredited
body for product certification fulfilling the requirements as per the ISO17065 standards. ECC has established rating
standards, along with an operating manual, for certifying evaporative air coolers and evaporative air-cooling equipment
with manufacturers in Europe and Australia.
ECC’s rating standards for evaporative air cooling components and equipment is sub-divided as follows:
• Direct Evaporative Cooling
• Indirect Evaporative Cooling
• Evaporative Cooling Equipment (ECE)
These are voluntary sub-programmes, meaning that applicants can, but do not have to, participate.

4.3.1.1 | Standard RS/9/C/004-2018 for DEC certification160

Key performance data considered for the certification as per this rating standard:
• Cooling capacity (kW)
• Airflow [m³/hr]
• Evaporation efficiency [%]
• EER
• Water consumption [L/hr] as per section 6.5 in ASHRAE 133-2015
For testing, the AS 2913-2000 standard and ASHRAE 133-2015 are used to calculate the following:
• Airflow (as per AS 2913-2000)
• Evaporation efficiency (as per AS 2913-2000), by calculating:
— Inlet dry-bulb temperature
— Inlet wet-bulb temperature
— Supply dry-bulb temperature
• Power consumption (as per AS 2913-2000)
• Water consumption
In addition to the above mentioned parameters, the following specific conditions are considered in the
qualification and repetition test:
• Operating conditions specified for the test (as per AS 2913-2000):
— Inlet dry-bulb temperature: 38°C
— Inlet wet-bulb temperature: 21°C
— Room dry-bulb temperature: 27.4°C
•W ater quality:
The manufacturer has to provide the following details on the water being supplied to the water distributor:
— Range of conductivity
— Range of total hardness
— Range of pH
— Range of Total Salt Content (TSC) or TDS
• The inlet water temperature shall not be lower than 10°C
• The inlet temperature readings by sensors shall be as per EN 14511-3:2013161

159
 urovent Certita Certification, 2018. Evaporative Cooling. [Online] Available at: https://www.eurovent-certification.com/en/third-party-certification/certification-programs/ec-
E
evaporative-cooling [Accessed 2020].
160 
Eurovent Certita Certification, 2018. Rating Standard for the Certification of Direct Evaporative Cooling, Paris: Eurovent Certita Certification.
EN 14511-3:2013: Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling - Part 3: Test methods
161 

64 // Decoding Evaporative Air Coolers

 Rating requirements:
Accepted Relative deviation
• S tandard air density of 1.20 kg/m3 shall be used in
the calculations. Cooling Capacity [kW] >_-5%
• A check-test shall be conducted to re-evaluate the Air Flow [m3/hr]
Chapter 4 >_-5%
performance under the standard test operating
Saturation Efficiency [%] >_-5%
conditions, with the help of selection software. If the S
O
difference between the test result and re-calculated Water Consumption [l/hr] <_-5%
value is not as per the acceptance criteria shown EER >_-5%
below in Figure 30, the item fails the check-test. Air-mo
Figure 30: Acceptance Criteria for DEC Rating162 Devic

4.3.1.2 | Standard RS/9/C/005-2018 for IEC certification163

Integrate
There are two cases specified under this rating standard with a) primary outside air and b) separation of external and room air: to Air H
Exchan
Primary Air Inlet
Outside Air
Case A: In this case, the IEC has air-moving devices for both Case B: In this case, a packaged IEC has air-moving
the primary and secondary air passages, as shown below devices for both the primary and secondary air passages,
in Figure 31. As per the requirement, a single air-moving as shown below in Figure 32. For testing, ASHRAE 143-
device may be used for the primary and secondary air. 2015 is considered under this rating standard. Pump

Reservoir with
Water Inlet and

Secondary Air Secondary Air

Outlet Air Outlet Air

Air-moving Air-moving
Device Device

Cabinet

Integrated Air Integrated Air

to Air Heat Air-moving Primary Air to Air Heat
Exchanger Device Primary Air Inlet Air-moving Exchanger
Primary Air Inlet Outside Air Device Primary Air
Outside Air

Secondary air inlet

Discharge of Primary air or,
Outside air or, Secondary air inlet
Room exhaust air Outside air

Pump Pump

Reservoir with Reservoir with

Water Inlet and Drain Water Inlet and Drain

Secondary Air
Outlet Air
Figure 31: Standard RS/9/C/005-2018: IEC Case A164 Figure 32: Standard RS/9/C/005-2018: IEC Case B165

Key performance data considered for certification as Key performance data considered for certification as
Air-moving
Device per this rating standard: per this rating standard:
• Total cooling capacity [kW] • Total cooling capacity [kW]
• Room cooling capacity [kW] • Airflow [m³/hr]
• Airflow [m³/hr] • Wet-bulb approach effectiveness [%]
ntegrated Air
to Air Heat
Exchanger
• Cooling effectiveness [%] • Dry-bulb approach effectiveness [%]
• WPrimary
aterAirconsumption [L/hr] as per section 6.5 in ASHRAE • Water consumption [L/hr] as per section 6.5 in ASHRAE
133-2015 133-2015
• EER
Secondary air inlet
• EER
Outside air

ir with
nlet and Drain

162
Eurovent Certita Certification, 2018. Rating Standard for the Certification of Direct Evaporative Cooling, Paris: Eurovent Certita Certification.
163 
Eurovent Certita Certification, 2018. Rating Standards for the Certification of Indirect Evaporative Cooling, Paris: Eurovent Certita Certification.
164 
Ibid.
165 
Ibid.

Overview of International Institutional, Policy, and Regulatory Framework on Evaporative Air Coolers // 65
Rating requirements:
• S tandard air density of 1.20 kg/m3 shall be used in the calculations.
• A check-test shall be conducted to re-evaluate the performance under the standard test operating conditions, with the
help of selection software. If the difference between the test result and re-calculated value is not as per the acceptance
criteria shown below in Figure 33, the item fails the check-test.

Case A Accepted Relative deviation Case B Accepted Relative deviation

Total Cooling Capacity [kW] >_-5% Total Cooling Capacity [kW] >_-5%

Room Cooling Capacity [kW] >_-5% Air Flow [m3/hr] >_-5%

Air Flow [m3/hr] >_-5% Wet bulb approach effectiveness [%] >_-5%

Cooling Effectiveness [%] >_-5% Dry bulb approach effectiveness [%] >_-5%

Water Consumption [l/hr] <_-5% Water Consumption [l/hr] <_-5%

EER >_-5% EER >_-5%

Figure 33: Acceptance Criteria for IEC Rating166

4.3.1.3 | Standard RS/9/C/006-2018 for ECE certification167

The following types of evaporative cooling media can be considered under this rating standard:
• Water spray systems
• Cooling pads/media
• Ultrasonic units168
Key performance data considered for the certification as per this rating standard:
• Cooling capacity [kW]
• Evaporation efficiency [%]
• Water consumption [L/hr] as per section 6.5 in ASHRAE 133-2015
• EER
• Wet pressure drop [Pascal - Pa] & dry pressure drop [Pa]
The ECC’s rating programmes for evaporative cooling components and equipment does not include noise level and
water wastage/bled-off rate as parameters in their evaporative air cooler standards.
Table 11 below provides a comparison of the parameters covered with respect to evaporative air cooler performance
under IS 3315, ASHRAE’s testing standards, Australia standards (AS/NZS 2913-2000), California Code of Regulations,
Title 20, Iran Appliance Label & MEPS and ECC rating standards:
Table 11: Comparative Summary of Evaporative Air Cooler Performance Parameters*

Parameters IS ASHRAE Testing Australia California, USA Iran Appliance ECC rating standards
3315 Standards (133 (AS/NZS (California Code of Label & MEPS (RS/9/C/004-2018,
& 143) 2913-2000) Regulations, Title 20) (4910-2) RS/9/C/005-2018, & ECE)

Water As defined in section 6.5

Consumption ‘Water Flow’ in ASHRAE
133-2015

Water ASHRAE
Entertainment 133-2015

Water Quality ASHRAE

133-2015

Power
Consumption

Noise Level

166
Ibid.
167 
Eurovent Certita Certification, 2018. Rating Standards for the Certification of Evaporative Cooling Equipment, Paris: Eurovent Certita Certification.
168 
Units that generate fine mist by converting an electronic signal into a mechanical oscillation.

66 // Decoding Evaporative Air Coolers

 Parameters IS ASHRAE Testing Australia California, USA Iran Appliance ECC rating standards
3315 Standards (133 (AS/NZS (California Code of Label & MEPS (RS/9/C/004-2018,
& 143) 2913-2000) Regulations, Title 20) (4910-2) RS/9/C/005-2018, & ECE)

Design & Build

Air Flow

Evaporative Cooling
Effectiveness

Static Pressure/ Not Not Not

Pressure Drop Specified Specified Specified

Testing Protocols

MEPS

Guidance &
Instructions for
Manufacturers

Eco-mark

Detailed
Specifications w.r.t.
Evaporative Air
Cooler Type

Parameter Covered Parameter NOT Covered

For an evaporative air cooler, water and power evaporative cooling pad effectiveness, and the rate
consumption are the two main parameters that can of evaporation/evaporative effectiveness has been
affect its overall performance and energy efficiency. covered by all the abovementioned testing standards,
From Table 11 shown above, one can see that power regulations, and MEPS. Static pressure has been covered
consumption has been covered as a parameter by all by IS 3315, ASHRAE 133 and 143, and the ECC voluntary
the reviewed testing standards, regulations, and MEPS, rating standards.
both nationally and internationally. However, in contrast,
Most important, information on the testing protocols for
water consumption has only been covered by the ECC’s
evaporative air coolers has been provided by IS 3315,
voluntary rating standards for evaporative air coolers,
ASHRAE 133 and 143, AS/NZS 2913-2000, California
even though water consumption is an equally important
Code of Regulations, Title 20, Iran Appliance Label &
parameter, because water is used as a refrigerant during
MEPS (4910-2), and the ECC voluntary rating standards.
the process of evaporation in evaporative air coolers.
One important finding from the review was that only
In addition to this, water entrainment, has only been
Iran has introduced MEPS for evaporative air coolers.
touched upon briefly by ASHRAE 133-2015, the DEC
Eco-mark is also another critical parameter that came
testing standard, in terms of how it can be detected.
out of the literature review and has only been adopted
Furthermore, water quality has only been covered
under IS 3315. In addition to this, details/parameters on
by ASHRAE 133-2015 and the ECC voluntary rating
different types of evaporative air coolers have only been
standards.
specified under the ASHRAE Testing Standards and ECC
The noise level has only been covered by IS 3315 voluntary rating standards.
and AS/NZS 2913-2000. The requirement for safety,
Furthermore, the recommendations based on the
exterior structure/design & build, as well as guidance &
international policy review are provided in the following
instructions for manufacturers, has only been covered
chapter.
by IS 3315. Other important parameters, namely, airflow,

Overview of International Institutional, Policy, and Regulatory Framework on Evaporative Air Coolers // 67
5
Conclusion &
Recommendations
From the review of international and national
institutional, policy, and regulatory frameworks
in regards to improving the performance of
evaporative air coolers, the following gaps have
been identified at the national level in terms of
‘policy and regulatory’, and ‘research and design’.
The gaps are followed by recommendations to
address them in the near future.
5.1 | National Level Gaps
The following gaps have been identified from the extensive literature review of international evaporative air cooler
testing standards, regulations, and MEPS:

5.1.1 | Policy & Regulatory Related

• Absence of MEPS & labelling for evaporative air coolers.
• Lack of specification for different evaporative air cooler types in the existing standards.
• L ack of consideration for water consumption, water quality, and water bled-off rates as one of the critical parameters
in the existing standards.
• Lack of focus on thermal comfort in the available appliance standards.
• Lack of evaporative air cooler testing infrastructure.

5.1.2 | Research & Design Related

• L ack of discussion about thermal comfort or the need for space cooling technologies for academic institutions (such as
schools, kindergartens, and universities) and evaporative air coolers’ potential application in these settings.
• L ack of literature available and research done on unlocking the market and technology potential of evaporative air
coolers in the commercial sector.
• IS 3315 2019 covered the design and construction specifications related to overall evaporative air cooler structure,
cooling pad material, and blower fan material and quality. However, specifications related to different types of blower
fans are not included. Moreover, the standard does not cover any information on the heat exchanger type, quality,
and material.

5.2 | Recommendations
To address the above-mentioned gaps, the following is recommended for India, based on the learnings from the testing
standards, regulations, and MEPS adopted internationally:

5.2.1 | Policy & Regulatory Related

The following recommendations could be taken up by Ministries: MoP, MoEF&CC, MoCI, and Ministry of Consumer
Affairs, Food, and Public Distribution; and Regulatory Bodies: BEE, BIS, IBEF, and CPRI, in consultation with key
Associations: ISHRAE and CEAMA, for robust policy uptake and adoption, and market transformation. Industry level
stakeholders, testing labs, and other private stakeholders could provide support in disseminating technical knowledge
and establishing testing infrastructure.

70 // Decoding Evaporative Air Coolers

 I. Establishment of MEPS

To establish MEPS for evaporative air coolers at the national level, the following parameters for evaluating evaporative
air cooler output and performance should be considered:
• Cooling Capacity: The cooling capacity of an evaporative air cooler is dependent upon the evaporation effectiveness,
inlet air’s dry- and wet-bulb temperatures, and airflow rate. As specified in Section 2.2, the evaporative effectiveness
ranges from 40% to 115%, depending on the type of evaporative air cooler, and the evaporative efficiency of the
cooling pad is around 85%, depending on the pad type. The Seasonal Energy Efficiency Ratio (SEER) star rating
bands should be designed taking these components under consideration.
• SEER: Similar to ISEER, which is used by BEE as the key parameter for evaluating the annual energy performance of
air conditioners, and considering India’s tropical climate, SEER would be an ideal parameter to evaluate evaporative
air coolers’ annual energy performance, where there is a change in seasonal temperatures, resulting in variation in
the cooling needs and energy required to operate appliances.
SEER is the annual performance ratio of the total annual cooling capacity to the total annual electrical energy
consumption of a particular unit, in a specific location, seasonally. In other words, it is a coefficient of performance that
evaluates the ratio of the annual amount of heat removed by a cooling appliance to the total annual amount of electrical energy
consumed by the appliance during this process, seasonally169. SEER considers the temperature at which the appliance
operates. The higher the SEER rating, the greater the energy efficiency of the appliance. The following equation can be
used to calculate SEER:
SEER of evaporative air cooler = total annual cooling capacity (kWh thermal)/Total annual electrical energy
consumption (kWh electric)170
For calculating the total electrical energy consumption, the following should be included:
• Number of hours per year when cooling is required to provide thermal comfort.
• Number of hours per year when the system is unable to provide thermal comfort.
• Average daily electrical energy use for cooling under the location-specific design conditions.
MEPS could also be specified as per the different types of evaporative air coolers, i.e. DEC, IEC, and IDEC.

II. Development of Label

For the development of performance labels for

evaporative air coolers in India, a comprehensive
comparative assessment of different labels/labelling
programmes worldwide should be undertaken, so
that recommendations regarding labelling based on
international best practices—which can be adapted to
the Indian climatic conditions—can be provided.

169
Purushothama, B., 2009. Humidification and ventilation management in textile industry. Research Gate, Issue 10.1533/9780857092847.
170 
Saman, W., Bruno, F., & Tay, S., 2010. Technical Research on Evaporative Air Conditioners and Feasibility of Rating their Energy Performance: Institute for Sustainable Systems and
Technologies

Conclusion & Recommendations // 71

 III. Capacity Building and Awareness Generation for Faster Performance Label Adoption

•  apacity building and awareness generation strategies should be developed to increase the adoption of water- and
C
energy-efficient evaporative air coolers and enhance potential consumers’ understanding of the water & energy
performance labels for evaporative air coolers.
• Incentivisation could help increase the uptake of water and energy-efficient evaporative air coolers.
•  ehaviour change campaigns should be implemented to facilitate the transition in consumers’ purchasing decisions
B
to opting for a sustainable and Non-GWP refrigerant based space cooling technology.
•  here should be consultations between the associations or Industry level stakeholders or the private stakeholders
T
and retailers and shopkeepers, who are in direct contact with consumers, to make them aware of the benefits
of energy-efficient and sustainable cooling technologies. This could aid in the dissemination of this information
through word-of-mouth to potential consumers.
To establish effective MEPS & labelling for evaporative air coolers in India, the following parameters, shown below in
Figure 34, should be considered under mandatory regulations and should be tested to evaluate the performance and
overall water and energy efficiency of evaporative air coolers, once the steady temperature and testing conditions
are achieved in a test lab at each selected speed level:

• Climatic conditions • Hours of operation (before testing)

• Relative Humidity (RH) • Static Pressure drop

• E xterior structure/design & build: Type and quality • Wet-bulb depression across the cooling system

• Type of heat exchanger • Sound level

• T emperature: Inlet and outlet dry and wet-bulb • Water:

temperatures — Inlet water quality
— Total water consumption
— Total water dumped off/wasted
• T otal electrical power consumption: by the sub-
— Water pump type, motor and quality
components-fan, water circulation pump and
variable speed control/remote system
• Air flow:
— Fan type, blade size and quality
• E vaporative cooling pad and rate of evaporation:
— Air flow rates at different speed settings subject to a
— Type of evaporating medium standardized pressure drop to allow for the ducting system.
— Thickness of cooling pad/media — Supply air flow through heat exchanger

Figure 34: Key Parameters for Evaporative Air Cooler MEPS & Labelling in India

These components will help in calculating the overall cooling capacity, evaporative effectiveness, and SEER or potential EER for evaporative air coolers. In addition to these
parameters, policymakers should make thermal comfort a priority in the available appliance standards and accelerate the efforts towards mainstreaming the available energy-efficient
space cooling technologies.

IV. Establishment of Testing Infrastructure

• Mapping of the existing government, private, and industry test labs in India available for evaporative air cooler
performance testing should be undertaken.
•  n assessment of the above-mentioned government, private, and industry test labs in India and their testing
A
infrastructure should be conducted. The evaluation and gap assessment of the testing infrastructure would highlight
the need for their upgradation as per the global standards on appliance testing.
• The test labs should be upgraded and new test labs should be set-up as required based on the gap assessment.
•  standard operating procedure (SoP) for the testing of evaporative air coolers and other similar Non-GWP refrigerant
A
based space cooling technologies should be developed.

72 // Decoding Evaporative Air Coolers

 5.2.2| Research & Design Related
The following recommendations could be taken up by Civil Society Organisations (CSOs), private players, academic and
research institutions, Original Equipment Manufacturers (OEMs), and technology providers for robust implementation and
rapid information dissemination of information and evaporative air cooler technology.
• A technology assessment study should be undertaken in schools, kindergartens, universities, and other academic
institutions to determine which type of evaporative air cooler is best suited for these settings, for achieving thermal
comfort.
•  n in-depth market transformation potential study is required to assess the actual potential of evaporative air coolers
A
in the commercial segment. SEEP for evaporative air coolers could be proposed, as they have high growth potential
in the Indian appliance market.
•  design SoP or design guidelines should be developed for heat exchangers and blower fans. Tentative design
A
guidelines are provided in Annexure 4.

Other Possible Interventions

In addition to the above-mentioned recommendations, the following interventions can be
introduced to support the implementation of MEPS for evaporative air coolers and increase
evaporative air coolers uptake in Indian appliance market:
An HERS171 index for the residential and commercial sectors could be developed
to help consumers compare the energy consumption levels amongst the setting
which has evaporative air coolers installed to the setting with energy intensive
space cooling appliances which use refrigerants with GWP such as air conditioners.
This will aid in altering consumer behaviour and fostering increase in uptake of
evaporative air coolers. This index could also be sent to consumers who are
currently using evaporative air coolers, to motivate them to continue using this Non-
GWP refrigerant based space cooling technology to limit their energy consumption
and do their bit in protecting the environment.
A pilot study to mainstream evaporative air coolers should be conducted that
entails in-situ performance and energy consumption assessments in a sample
household and commercial/industrial settings with evaporative air coolers. This
study could be linked to an incentivisation mechanism such as a tax rebate or
differential tariff pricing.
In terms of achieving thermal comfort, apart from the residential or commercial
sector, there is one area that has been overlooked that is thermal comfort for
children. Efforts should be made should be to provide thermal comfort in settings
used by children such as orphanages, schools, kindergartens, and other academic
institutions and areas that currently lack access to thermal comfort.
 ‘pay-per-use’ model or servitisation for evaporative air coolers should be adopted.
A
In servitisation, the consumer pays the price of per unit energy consumed by them
or service provided by an appliance. In this model, the technology provider remains
the appliance owner and covers the capital and operational costs of the appliance.
This service model is beneficial for both the manufacturer and consumers and
could increase evaporative air cooler penetration. This, in turn, would promote the
use of energy-efficient Non-GWP refrigerant based space cooling technologies,
facilitating access to cooling and thermal comfort for all.

171
 he Home Energy Rating System (HERS) Index is sent to customers separately from their utility bills on a monthly, bimonthly, or quarterly basis. It includes a summary of the
T
home’s recent and historical energy use, energy efficiency tips (including utility energy efficiency programme offerings), and a normative comparison of the home’s energy use
to that of similar neighbours and offers rewards or incentives for reducing energy use. It is also frequently accompanied by a web portal, available to customers, that provides
similar information.

April 2021 // 73
Conclusion & Recommendations
Way Forward
The development of the MEPS framework will provide an
opportunity to standardise this product segment, increasing its
mass adoption and, ultimately, increasing access to cooling
and thermal comfort for all, as well as providing other related
co-benefits such as a reduction in GWP and GHG emissions.
Nevertheless, it is essential to first assess the present market,
future growth, and energy saving potential of evaporative air
coolers in the commercial sector, as there is extremely limited
information available on the commercial evaporative air
cooler market compared to the residential air cooler market.
Getting ahead of the demand curve and setting robust MEPS The development of the MEPS
for evaporative air coolers could help in establishing market- framework will provide an opportunity
leading performance and setting India’s evaporative air cooler to standardise this product segment,
industry ahead of other international competitors. This could increasing its mass adoption and,
position India as the market leader for export opportunities, ultimately, increasing access to cooling
in addition to domestic trade, and could contribute towards and thermal comfort for all, as well as
economic recovery, along with supporting the Government providing other related co-benefits
of India’s ‘Atmanirbhar Bharat’ initiative. Therefore, extensive, such as a reduction in GWP and GHG
focused efforts are required to leverage the existing evaporative emissions.
air cooler technology in the commercial sector and develop
its MEPS to enable wider market adoption. AEEE’s follow-up
report on this subject will thus focus on a technology and market
assessment of India’s major evaporative air cooler market
players in the commercial sector.

74 // Decoding Evaporative Air Coolers

Annexure 1
BIS Standards test conditions for testing evaporative air coolers:

•  ooling efficiency and air delivery can be

C cooling efficiency, as desired. It shall operate
tested on any prevailing ambient temperature. in this condition until it reaches its thermal
equilibrium.
• Relative humidity for in-let air to be between 25
% and 55% with variation not more than ± 5%. • tandard operating condition is said to be
S
achieved when the dry-bulb temperature is
• Cooling pads shall be dry during air flow test. recorded at same position and it does not
•  he static pressure difference between cooled
T change more than 0.5°C within the interval of 15
supply air and the ambient conditions of inlet mins. This test is continued until five successful
air cooler in the test room shall be adjusted readings are achieved.
to provide zero static pressure with the help of •  he dry-bulb temperature of the supply cooled
T
blower fan and damper. air shall be around 1.5°C.
• Power consumption shall be tested at zero
 •  he frequency and voltage supply to the air
T
static pressure. cooler shall be adjusted ± 2% of the motor
•  cooler shall be operated under conditions
A rated voltage.
when it is providing maximum air delivery and

Annexure 1 // 75
Annexure 2
Key highlights from review of the ASHRAE Standard 133-2015: Method of Testing Direct Evaporative Air Coolers are
mentioned below172:

1. Requirements: being circulated to the water distributer.

The conductivity shall be between 350 and
•  etermination: A series of measurements are
D
3500 microsiemens (μS). The meter shall be
carried out for a particular point of operation
calibrated as per the manufacturer with the
of an evaporative air cooler, for estimating the
help of a certified calibration solution.
performance variables as mentioned under
this standard, from the range of shutoff173 to free — Entrainment Verification: The air testing
delivery174 and are depended upon the various equipment shall be kept safe from
characteristic curves. Eight measurements water entrainment, to avoid alteration in
shall be taken to determine the curves that are temperature readings.
not smooth. In case of performance estimation
at a point of operation than at least three
measurements are required to determine the
short curve inclusive of that point.

• eaching equilibrium: Before starting to

R
take actual measurements/readings, trial
observations shall be made in order to
check for equilibrium conditions or steady
readings. The range of air delivery over which
equilibrium can’t be achieved shall be taken
into considerations, as a reading.
Figure 35: A measurement device for air flow:
•  tability: The airflow rate shall be recorded, at
S psychrometer with sample tree175
which two different static pressure differential
points or the bi-stable performance points can 2. Instruments and methods of measurement:
be measured. These points could be set for
•  ir temperature measurements and measuring
A
reducing or increasing the airflow rate.
instruments shall be as per ANSI/ASHRAE
• 
Acceptable Standard Temperature and Standard 41.1.176 and shall display accuracy as
Humidity Test Conditions: mentioned below:
— Inlet air dry-bulb temperature: maximum: — Air wet-and dry-bulb temperatures: ±0.2°C
46°C (115°F). (0.40°F).
—W  et-bulb temperature: minimum: 5°C (41°F). — Other dry-bulb temperatures: ±0.30°C (0.50°F).
—W  et-bulb depression: minimum: 11°C (20°F). • he air temperature instrument shall be a
T
—During the test, the difference between psychrometer with sample tree, as shown in
the upstream and downstream wet-bulb Figure 35, which shall be able to take nine
temperature shall not be more than 1°C (2°F) equal samples in a chamber.177
during the test.
• o avoid loss of heat and moisture while
T
•  tandard water quality to be maintained:
S testing, the discharge from the instrument/
— Conductivity meter with an accuracy of psychrometer shall be sent back to the
±10% of observed reading shall be used chamber.
to measure water’s conductivity; which is

172
ANSI/ASHRAE Standard 133-2015, 2015, Method of Testing Direct Evaporative Coolers, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., Atlanta.
173 
the point of operation where the airflow rate is zero
174 
the point of operation where the external static pressure is zero.
175 
ANSI/ASHRAE Standard 133-2015, 2015, Method of Testing Direct Evaporative Coolers, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., Atlanta
176
Standard 41.1-1986 (RA 2001), Standard Method for Temperature Measurement
177 
A chamber is a laboratory set up to stimulate the conditions faced by an evaporative air cooler

76 // Decoding Evaporative Air Coolers

 • he smallest scale division of the air
T temperature, Fan speed (N), power input to
temperature instrument shall not exceed twice fan (Wf), Power input to pump (Wp), power
the specified accuracy. input to appurtenances (Wa), static pressure
differential, nozzle pressure differential and
•  alibration of the instrument shall be done by
C water conductivity.
comparing the value according to the National
Institute of Standards and Technology (NIST) •  he nameplate information and evaporative
T
certified thermometer, if the accuracy closer air coolers dimensions shall be cross-
than ±0.30°C (0.50°F) is measured. checked with the available drawing.

•  he wet-bulb temperature shall be measured

T •  he instruments used for the tests shall also be
T
only when evaporative equilibrium has been listed. The information of the following shall
achieved and the air velocity is between 3.5 to be included and recorded: names, model
10 m/s (700 to 2000 ft/min) over the wet-bulb numbers, serial numbers, scale ranges, and
temperature. calibration.

•  he pressure measurement shall be as per

T •  ame of the person conducting the particular
N
ASHRAE Standard 41.3.178 The permitted test shall also be listed.
accuracy is ±1% of the reading and the for the
barometric pressure it is ±34 Pa (0.01 in. Hg).
4. P
 erformance corrections to nominal or standard
•  he static pressure shall be measured with the
T airflow rate and speed:
help of special taps for eliminating velocity.
Following parameters need to be calculated
•  ir flow shall be calculated by measuring the
A from the test data:
pressure differential across the flow nozzles
in the chamber and shall be defined as per • Standard airflow rate
ASHRAE Standard 41.2.179 These nozzles are • Standard static pressure differential
not required to be calibrated if maintained
under specified conditions. • Fan standard power

• he power shall be measured using a

T • Standard power input
wattmeter with an accuracy of ±1.0%
• If the rotation speed varies from one reading to
of observed reading, connected to the
another, then the correction will be required in
evaporative air cooler.
the value calculated under the test conditions
• Water flow shall be measure with a water
 for converting it into a nominal fan speed at
meter of the accuracy of ±5.0% of observed standard density.
reading along with a timing device to measure
•  aturation Effectiveness shall be called as the
S
the rate of water flow.
function airflow rate corrected to standard air.
• peed shall be measured with the help
S
of speed measuring devices such as
chronometer and stroboscope or any other 5. Report & test results:
device with an accuracy of ±0.5% of the value
being measured.
•  he final lab test report of an evaporative air
T
cooler shall include details about the object,
results, test set-up, instruments for testing and
test data, about of the evaporative cooler/
3. Instructions for recording data:
cooling unit and the name of test lab.
•  he description of the test, its set-up and test
T
• erformance data shall be summarized in
P
readings shall be described/recorded.
a table for both packaged and component
•  ata to be tested for inlet dry and wet-bulb
D evaporative air cooler types.
temperature, downstream dry and wet-bulb

Standard Methods for Pressure Measurement (2014)

178 

Standard 41.2-1987 (RA 1992), Standard Methods for Laboratory Airflow Measurement
179 

Annexure 2 // 77
 • If the pump is not used for supplying water, than 0.5% for any test value, and the sum of
then the method of supplying water along the deviations shall be zero. If discontinuity
with the flow rate of water delivered to the occurs, it shall be displayed by broken lines.
coolers must be included in the final test •  erformance curve for package evaporative
P
report. air cooler: On x-axis evaporative air cooling
•  ll the components installed between the
A flow rate and standard static pressure
inlet and outlet boundaries of a testing setup differential, power input, and saturation
shall be included as a part of the cooling unit effectiveness to be plotted on y-axis. The
and the test results shall clearly state these fan’s speed will have a separate graph with
boundaries. its value on Y-axis if all the other values are
not nominal.
•  erformance curves to be used for concluding
P
the test results, with each reading taken/ •  erformance curve for component evaporative
P
recorded to be plotted on the graph. air cooler: On x-axis, air flow rate and static
pressure differential, standard power input,
• erformance curve to be plotted by using
P and saturation effectiveness to be plotted as
test points/recorded readings. The curves ordinates on y-axis.
shall not deviate from the test points by more

78 // Decoding Evaporative Air Coolers

Annexure 3
Key highlights from review of the ASHRAE Standard 143-2015: Method of Test for Rating Indirect Evaporative Coolers
are mentioned below180:

1. T
he indirect evaporative air coolers are sub-
divided into the following four categories as per
their construction style:

• Component Indirect Evaporative Coolers: As

shown in Figure 36, this type is a basic type of
an indirect evaporative cooler have integrated
heat exchanger. There are no primary and
secondary air moving devices.

Figure 38: Semipackaged Secondary IEC with

nonintegrated sensible and evaporative HE183

•  emi-packaged Primary Indirect Evaporative

S
Coolers: This type of IEC includes an
integrated heat exchanger with the primary
air-moving device as shown below in the
Figure 36: Component IEC181 Figure 39.

• Semi-packaged Secondary Indirect Evaporative

Coolers: This type of IEC includes secondary
air moving device but no primary air-moving
device as shown below in Figure 37 and Figure
38. There can be two types of semi-packaged
indirect evaporative air coolers: the one with
integrated heat exchanger and the other one
with non-integrated heat exchanger and an
evaporative precooler heat exchanger.

Figure 39: Primary IEC184

• 
Packaged Indirect Evaporative Coolers:
This type of IEC includes an integrated heat
exchanger with primary and secondary
air-moving devices, as shown below in
Figure 40.
Figure 37: Semi Packaged Secondary IEC with
integrated air-to air HE182

180 
ANSI/ASHRAE Standard 143-2015, 2015, Method of Test for Rating Indirect Evaporative Coolers, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., Atlanta.
Ibid.
181 

182
Ibid.
183 
Ibid.
184 
Ibid.

Annexure 3 // 79
 comparing the value according to the National
Institute of Standards and Technology (NIST)
certified thermometer, if the accuracy closer
than ±0.30°C (0.50°F) is measured.

• et-bulb temperature shall be measured

W
only when evaporative equilibrium has been
achieved and the air velocity is under the range
of 700 to 2000 ft/min (3.5 to 10 m/s) over the wet-
bulb, and preferably near 1000 ft/min (5 m/s).

•  o measure the change in temperature at the

T
supply and exhaust positions, temperature
Figure 40: Packaged IEC185 measuring instrument shall be used.

2. R
 equirements: • uring testing, psychometric measurement
D
stations shall be located uniformly, downstream
• irflow rates shall be measured for both
A of the measurement station.
primary and secondary air stream. Only
when the following two conditions are met, •  ressure measurement to be done with a liquid-
P
then the measurement of secondary airflow column manometer as per ASHRAE Standard
rate won’t be required but may be taken from 41.3. The instrument shall permit measurements
the previous testing: with ±1% of the reading.
—The appliance is a non-integrated indirect •  irflow rate shall measure as per ASHRAE
A
evaporative air cooler. Standard 41.2 and shall be estimated by
—A cooling tower is used as one of the measuring the pressure differential across
components of an indirect evaporative air the nozzles. A detailed description for nozzle
cooler and is certified under CTI Code ATC– apparatus, construction and its use with the
105. airflow apparatus, ASHRAE Standard 41.2
shall be followed.
• he temperature difference between the
T
in-let primary and secondary air shall be at •  alibration of the nozzles is not required if
C
least 20°F (11°C). is maintained as per the specified conditions.
The throat dimension L=0.6D is recommended
• o conclude a complete test result report, a
T
for testing airflow of indirect evaporative air
minimum of 5 readings is required to be taken.
cooler and the throat velocity shall not be
More than five readings may be required in
less than 3000 ft/min (15 m/s) nor greater than
case of discontinuities.
7000 ft/min (35 m/s).

• All power devices shall have the accuracy of

3. Instruments: ±1% of the observed reading.

• 
Temperature measurement and their
instruments shall be as per the ASHRAE
4. Apparatus:
Standard 41.1.
Temperature Measuring Apparatus: The
• he temperature measurement instruments
T
temperature measuring instrument shall be
shall show accuracy as per the following:
a psychrometer with sample tree, which shall
— Air wet- and dry-bulb temperatures, ±0.40°F be able to measure nine equal areas of the
(0.20°C). chamber. Both dry and wet-bulb temperature
— Other dry-bulb temperatures, ±0.50°F (0.30°C). shall be measured from the air-sampling
device. To avoid errors in reading, the
• The smallest scale division of the air

discharge from the instrument/psychrometer
temperature instrument shall not exceed twice
shall be sent back to the chamber. All
the specified accuracy.
temperature measurements shall be as per
• Calibration of the instrument shall be done by ASHRAE Standard 41.1.3.

185
ANSI/ASHRAE Standard 143-2015, 2015, Method of Test for Rating Indirect Evaporative Coolers, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., Atlanta.

80 // Decoding Evaporative Air Coolers

•  irflow Measuring Apparatus: For measuring
A density, thermodynamics, airflow and other
air flow rate the chamber shall consist of a parameters would establish the performance
receiving, discharge and nozzles section. The of the indirect evaporative air cooler.
nozzles shall be as per ASHRAE Standard 41.2. •  o calculate the overall pressure measurement;
T
•  ressure Measuring Apparatus: Special taps
P barometric reading, primary and secondary
would be required to measure static pressure, airflow, the pressure drop of both primary and
for removing the effect of velocity. The static secondary air are required to be recorded.
pressure at the inlet and discharge tap of •  o record the overall electric power required
T
indirect evaporative air cooler shall be set at to operate an indirect evaporative air cooler,
zero. the individual power requirement of a pump,
electric power input to appurtenances and
the electric power input to the fan motor of the
5. Testing Methods: primary and secondary air moving devices
The indirect evaporative cooling unit shall shall be recorded.
be installed in the test section as per the
manufacturer. More information can be taken
directly from ASHRAE Standard 143-2015, 10. Test Reports:
2015. •  he final lab test report of an evaporative
T
air cooler shall include details about the
object, results, test set-up, appurtenances,
6. Correct source of water and electricity instruments for testing and test data. The
shall be connected to the cooler. Wattmeter report shall include information such as type
shall be connected to the record power of indirect evaporative air cooler, information
consumption. The evaporative air cooler on the specific model of coolers as per the
shall be checked with bubble solution for manufacturer, test identification number,
leaks and then repaired for leaks, before about the test lab, date of testing and name
starting the testing. of the person who conducted the test.

•  he test report shall include the data related to

T
7. Equilibrium shall be achieved before starting barometric pressure, primary and secondary
the testing. The airflow rate for both primary air temperature, primary and secondary air
and secondary air stream shall be checked. flow rate, electric power input, and primary
Water distribution system and pump shall and secondary air static pressure drop.
function properly. Equipment shall be •  erformance curves of electricity inputs and
P
allowed to run until the wet-bulb temperature cooling capacity shall be included. In the
stabilizes. Water temperature shall remain case of indirect evaporative air coolers who
constant. Three consecutive readings shall does not have air-moving devices, their static
be recorded within three minutes of the same pressure drop curve shall also be included.
value, to verify steady readings that is an
equilibrium condition. •  ach recorded reading shall be shown on
E
the performance curve as a circled point. The
curve shall not deviate from the test points by
8. F
or semi-packaged or packaged indirect more than 0.5% of any test value, and the sum
evaporative air coolers, the primary and of the deviations shall be zero. If discontinuity
secondary airstream at the inlet and outlet occurs that is if equilibrium can’t be achieved
of the coolers shall provide zero static. for any reading then the curve joining those
points shall be displayed by broken lines.

•  atings for indirect evaporative air cooler is

R
9. F
or testing and calculating the overall inclusive of the application ratings given/used
performance of an indirect evaporative air at the time of selection of the appliance and
cooler, simultaneous reading at an interval conditions encountered. These application
of 2-mins shall be taken for electrical power ratings may be presented in the form of
consumption, temperature and pressure curves, tables, etc.
in order to calculate parameters such as

Annexure 3 // 81
Annexure 4
Evaporative air cooler’s design guidelines for manufacturers:

•  or blower fan: There are two primary types fans- Axial Flow fans and Centrifugal Fan, which should be
F
allowed to be used as the components of an evaporative air cooler, as per the requirement and setting, as
mentioned below in Table 12.
Table 12: Comparison Between Axial and Centrifugal Fans186

Parameters Axial Flow fans Centrifugal Fan

About Create high air flow rate at low pressures Best for high pressure applications. Provides
steadier flow as of axial fans. They can handle
contaminated air stream.

Type187

Power required Low power input required High power input required

Sector suitability Residential and small office spaces Industrial

•  or sensible heat exchanger: They should be tested for high thermal conductivity. The material type could
F
depend upon the requirements of the heat transfer application. Materials such as copper, titanium, stainless
steel heat exchangers, or plastics, should be allowed to be used for making a sensible heat exchanger.

186
Bureau of Energy Efficiency, 2020. Ch 5: 5. FANS AND BLOWERS, New Delhi: Bureau of Energy Efficiency
187 
Ibid.

82 // Decoding Evaporative Air Coolers

Bibliography
6wresearch, 2019. India Air Cooler Market (2019-2025). [Online] Available at: https://www.6wresearch.
com/industry-report/india-air-cooler-market-2019-2025#:~:text=According%20to%206Wresearch%2C%20
India%20Air,with%20the%20demonetization%20in%202016

Abhyankar, N., Shah, N., Park, W. Y. & Phadke, A., 2017. Accelerating Energy-Efficiency Improvements in
Room Air Conditioners, United States: Ernest Orlando Lawrence Berkeley National laboratory.

Agrawal, S., Mani, S., Aggarwal, D., Kumar, C.H., Ganesan, K., & Jain, A., 2020. Awareness and Adoption of
Energy Efficiency in Indian Homes: Insights from the India Residential Energy Survey (IRES) 2020, New Delhi:
Council on Energy, Environment and Water.

Amer , O., Boukhanouf, R. & Ibrahim, H. G. A., 2015. A Review of Evaporative Cooling Technologies.
International Journal of Environmental Science and Development, Volume V6.571.

Amer, O., Boukhanouf, R. & Ibrahim, H. G. A., 2015. A classification of evaporative cooling systems in building
cooling. Available at: https://www.researchgate.net/publication/265890843_A_Review_of_Evaporative_
Cooling_Technologies?enrichId=rgreq-6d19e6de5aa5b93ace10bbb7df1b0364-

Amer, O., Boukhanouf, R. & Ibrahim, H. G. A., 2015. IEC structure. Available at: https://www.researchgate.
net/publication/265890843_A_Review_of_Evaporative_Cooling_Technologies?enrichId=rgreq-
6d19e6de5aa5b93ace10bbb7df1b0364-XXX&enrichSource=Y292ZXJQYWdlOzI2NTg5MDg0MztBUzoxNjUx
OTgyMjg4OTM2OTdAMTQxNjM5NzczNTk5Nw%3D%3D&el=1_x_3&_esc=publicationCoverPdf

Amer, O., Boukhanouf, R. & Ibrahim, H. G. A., 2015. Two-stage IDEC system. Available at: https://www.
researchgate.net/publication/265890843_A_Review_of_Evaporative_Cooling_Technologies?enrichId=rgreq-
6d19e6de5aa5b93ace10bbb7df1b0364-XXX&enrichSource=Y292ZXJQYWdlOzI2NTg5MDg0MztBUzoxNjUx
OTgyMjg4OTM2OTdAMTQxNjM5NzczNTk5Nw%3D%3D&el=1_x_3&_esc=publicationCoverPdf
ANSI/ASHRAE Standard 133-2015, 2015, Method of Testing Direct Evaporative Coolers, American Society of
Heating, Refrigerating and Air-Conditioning Engineers, Inc., Atlanta.

ANSI/ASHRAE Standard 143-2015, 2015, Method of Test for Rating Indirect Evaporative Coolers, American
Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., Atlanta.

ASHRAE, 2017. STANDARD 55 – Thermal Environmental Conditions for Human Occupancy. [Online] Available
at: https://www.ashrae.org/technical-resources/bookstore/standard-55-thermal-environmental-conditions-for-
human-occupancy

Australian Government, 2017. Inspections and enforcement. [Online] Available at: https://www.waterrating.
gov.au/enforce [Accessed 2020].

Australian Government, 2020. Energy rating label. [Online] Available at: https://www.energy.gov.au/rebates/
energy-rating-label [Accessed 2020].

BEE, 2017. Hiring of Consultant for Technical Study for Equipment & Appliances for Standard & Labelling,
New Delhi: BEE.

Bureau of Energy Efficiency, 2016. Guidelines for the Permittee-Standardsa and Labelling program of BEE,
New Delhi: Bureau of Energy Efficiency.

Bureau of Energy Efficiency, 2018. National Mission for Enhanced Energy Efficiency, New Delhi: Bureau of
Energy Efficiency.

Bureau of Energy Efficiency, 2019. Enforcement Machinery under Energy Conservation Act, 2001, New Delhi:
Bureau of Energy Efficiency.

Bibliography // 83
 Bureau of Energy Efficiency, 2019. Impact of Energy Efficiency Measures for the Year 2017-18, New Delhi:
Bureau of Energy Efficiency.

Bureau of Energy Efficiency, 2020. About BEE. [Online] Available at: https://beeindia.gov.in/content/about-
bee[Accessed 2020].

Bureau of Energy Efficiency, 2020. BLY. [Online] Available at: https://beeindia.gov.in/content/bly-1

Bureau of Energy Efficiency, 2020. Ch 5: 5. Fans And Blowers, New Delhi: Bureau of Energy Efficiency

Bureau of Energy Efficiency, 2020. EEFP. [Online] Available at: https://beeindia.gov.in/content/eefp

Bureau of Energy Efficiency, 2020. FEEED. [Online] Available at: https://beeindia.gov.in/content/feeed

Bureau of Energy Efficiency, 2020. Lab Capacity Building. [Online] Available at: https://beeindia.gov.in/content/
lab-capacity-building

Bureau of Energy Efficiency, 2020. MTEE. [Online] Available at: https://beeindia.gov.in/content/mtee-0

Bureau of Energy Efficiency, 2020. NMEEE. [Online] Available at: https://beeindia.gov.in/content/nmeee-1

[Accessed 2020].

Bureau of Energy Efficiency, 2020. PAT. [Online] Available at: https://beeindia.gov.in/content/pat-3

Bureau of Energy Efficiency, 2020. SEEP. [Online] Available at: https://beeindia.gov.in/content/seep-0

Bureau of Energy Efficiency, 2020. Standards & Labeling. [Online] Available at: https://beeindia.gov.in/content/
standards-labeling

Bureau of Energy Efficiency, 2020. Star Labelled Appliances. [Online] Available at: https://beeindia.gov.in/
content/star-labelled-appliances

Bureau of Indian Standards, 2016. National Building Code of India 2016 Volume 2, New Delhi: Bureau of
Indian Standards.

Bureau of Indian Standards, 2019. Evaporative Air Coolers ( Desert Coolers ) — Specification (Third Revision).
IS 3315: 2019. New Delhi: Bureau of Indian Standards.

Bureau of Indian Standards, 2020. About BIS. [Online] Available at: https://bis.gov.in/index.php/the-bureau/
about-bis/ [Accessed 2020].

California Energy Comission, 2020. About. [Online] Available at: https://www.energy.ca.gov/

about#:~:text=The%20Warren%E2%80%90Alquist%20Act%20established,and%20reliable%20supply%20
of%20energy.[Accessed 2020].

California Energy Commission, 2006. The Appliance Efficiency Regulations, Title 20, CEC-400-2006-002.

California Energy Commission, 2017. 2016 Appliance Efficiency Regulations. California Energy Commission.
CEC-410-2017-002

California Energy Commission, 2019. Efficiency Division. [Online] Available at: https://www.energy.ca.gov/
about/divisions-and-offices/efficiency-division [Accessed 2020].

Carolyn , R., Chase, A., Marver, j., Cunningham, k., Wilkins, B. and McLain, L., 2016. Developing an Appliance
Standards Compliance Improvement Program. Pacific Grove, ACEEE Summer Study on Energy Efficiency in
Buildings.

Central Power Research Institute, 2020. About CPRI. [Online] Available at: https://www.cpri.in/about-cpri.html
[Accessed 2020].

CLASP, 2020. Policy Details. [Online] Available at: https://clasp.ngo/policies/iran-meps11[Accessed 2020].

Consumer Electronics and Appliances Manufacturers Association, 2020. Association Overview. [Online]
Available at: https://ceama.in/AssociationOverview.html [Accessed 2020].

Department of Consumer Affairs, 2020. Vision and Mission. [Online] Available at: https://consumeraffairs.nic.
in/vision-and-mission [Accessed 2020].

84 // Decoding Evaporative Air Coolers

Department of Food & Public Distribution, 2018. About Us. [Online] Available at: https://dfpd.gov.in/about-us.
htm [Accessed 2020].

Dincer, I. & Rosen, M. A., 2007. Chapter 6 - Exergy Analysis of Psychrometric Processes. EXERGY, Elsevier,
pp. 76-90.

Effatnejad, R. and Salehian, A.B., 2009. Standard of energy consumption and energy labeling in evaporative
air cooler in Iran. Jurnal IJTPE, 1.

Energy Rating, 2020. About the E3 Program. [Online] Available at: https://www.energyrating.gov.au/about-e3-
program [Accessed 2020].

Eurovent Certita Certification, 2018. Evaporative Cooling. [Online] Available at: https://www.eurovent-
certification.com/en/third-party-certification/certification-programs/ec-evaporative-cooling [Accessed 2020].

Eurovent Certita Certification, 2018. Rating Standard for the Certification of Direct Evaporative Cooling, Paris:
Eurovent Certita Certification.

Eurovent Certita Certification, 2018. Rating Standards for the Certification of Indirect Evaporative Cooling, Paris:
Eurovent Certita Certification.

Eurovent Certita Certification, 2018. Rating Standards for the Certification of Evaporative Cooling Equipment,
Paris: Eurovent Certita Certification.

fairconditioning, 2019. Evaporative Cooling. [Online] Available at: http://fairconditioning.org/knowledge/sustainable-

cooling-technologies/evaporative-cooling/#1500552370074-430ff37c-6e5440f0-dcf0

Fairconditioning. Engineering Principle – Indirect Evaporative Cooling, Evaporative Cooling., Fairconditioning.

Available at: http://fairconditioning.org/knowledge/sustainable-cooling-technologies/evaporative-
cooling/#1500296799628-e5546709-43d940f0-dcf0

Fairconditioning. Engineering Principle - Indirect-Direct Evaporative Cooling, Evaporative Cooling.,

Fairconditioning. Available at: http://fairconditioning.org/knowledge/sustainable-cooling-technologies/
evaporative-cooling/#1500296799628-e5546709-43d940f0-dcf0

Gatley, D. P., 2013. Understanding Psychrometrics, Atlanta: American Society of Heating, Refrigerating and Air-
Conditioning Engineers (ASHRAE).

Govekar, N., Bhosale, A. & Yadav, A., 2015. Modern Evaporative Cooler. International Journal of Innovations in
Engineering Research and Technology [IJIERT], 2(4).
Grand View Research, 2019. Air Coolers Market Size, Share & Trends Analysis Report By Type (Tower, Dessert),
By Application (Residential, Commercial), By Region (North America, Europe, APAC, CSA, MEA), And Segment
Forecasts, 2019 - 2025, California: Grand View Research.

HMX, 2020. HMX-Ambiator. [Online] Available at: https://www.ategroup.com/hmx/product-family/product-

description/hmx-ambiator/

HMX, 2020. HMX-IEC. [Online] Available at: https://www.ategroup.com/hmx/cooling/product-family/stand-alone-

cooling-units/

India Brand Equity Foundation, 2020. About India Brand Equity Foundation. [Online] Available at: https://www.
ibef.org/about-us.aspx [Accessed 2020].

Indian Society of Heating, Refrigerating and Air Conditioning Engineers, 2020. https://ishrae.in/Home/Aim_
objectives. [Online] Available at: https://ishrae.in/Home/about_ishrae [Accessed 2020].

Institute of Standards & Industrial Research of Iran, 2020. Introduction. [Online] Available at: http://www.isiri.com/
about.htm [Accessed 2020].

Jain , A., 2019. Desert Air Coolers better option than Air Conditioners for hot and dry places, s.l.: Bijli Bachao.

Jain, A., 2020. Bijli Bachao. [Online] Available at: https://www.bijlibachao.com/air-conditioners/best-air-cooler-

india-brand.html [Accessed 2020].

Bibliography // 85
 Jain, J. & Hindoliya, D., 2013. Energy saving potential of indirect evaporative cooler under Indian climates.
International Journal of Low-Carbon Technologies 2016, p. 193–198.

Kanchwala, H., 2020. BLDC Fans (super efficient fans) in India 2020 - Market Analysis. [Online] Available at:
https://www.bijlibachao.com/fans/bldc-fans-super-efficient-fans-in-india-market-analysis.html

Lalit, R. & Kalanki, A., 2019. How India is solving its cooling challenge. [Online] Available at: https://www.
weforum.org/agenda/2019/05/india-heat-cooling-challenge-temperature-air-conditioning/ [Accessed 2020].

Lalit, R. and Kalanki, A., 2019. Cooling Demand Versus Current AC Ownership in Different Parts of The World.
[image] Available at: https://www.weforum.org/agenda/2019/05/india-heat-cooling-challenge-temperature-
air-conditioning[Accessed 17 January 2020].

Ministry of Commerce and Industry, 2020. Department setup and function. [Online] Available at: https://
commerce.gov.in/about-us/department-of-commerce/department-setup-and-function/ [Accessed 2020].

Ministry of Commerce and Industry, 2020. Vision, Mission and Message. [Online] Available at: https://
commerce.gov.in/[Accessed 2020].

Ministry of Electronics & Information Technology, 2019. Vision & Mission. [Online] Available at: https://www.
meity.gov.in/about-meity/vision-mission[Accessed 2020].

Ministry of Environment, Forest & Climate Change, 2019. India Cooling Action Plan, New Delhi: Ministry of
Environment, Forest & Climate Change..

Ministry of Environment, Forest and Climate Change, 2020. Introduction. [Online] Available at: http://moef.
gov.in/about-the-ministry/introduction-8/Ministry of Electronics & Information Technology

Ministry of Environment, Forest & Climate Change, 2017. HCFC Phase-Out Management Plan Stage II, New
Delhi: Ministry of Environment, Forest & Climate Change.

Ministry of Power, 2020. About Ministry. [Online] Available at: https://powermin.nic.in/en/content/about-

ministry [Accessed 2020].

Ministry of Power, 2020. Energy Efficiency. [Online] Available at: https://www.powermin.nic.in/en/content/

energy-efficiency [Accessed 2020].

Ministry of Power, 2020. Responsibilities. [Online] Available at: https://powermin.nic.in/en/content/

responsibilities [Accessed 2020].
Pandita, S., Kishore Kumar , P., Walia, A. & Ashwin, T., 2020. Policy measures and impact on the market for the
Room Air. [Online] Available at: https://clasp.ngo/publications/policy-measures-and-impact-on-the-market-for-
room-air-conditioners-in-india

Pascholda, H., Lia,b, W.-W., Moralesa, H. & Walton, J., 2003. Laboratory study of the impact of evaporative
coolers on indoor PM concentrations. Atmospheric Environment, Elsevier, p. 1075–1086.

Piattelli, C., 2016. Evaporative cooling. Powrmatic. Available at: https://www.powrmatic.co.uk/blog/

evaporative-cooling-work/

Piattelli, C., 2016. Latent Energy Vs Sensible Energy. Powrmatic. Available at: https://www.powrmatic.co.uk/
blog/evaporative-cooling-work/

Purushothama, B., 2009. Humidification and ventilation management in textile industry. Research Gate, Issue
10.1533/9780857092847.

REHVA, 2012. Definitions of terms and abbreviations commonly used in REHVA publications and in HVAC
practice, s.l.: REHVA.

Research and Markets, 2015. India Air Cooler Market Outlook, 2021, India: Research and Markets.

Research and Markets, 2019. India Air Cooler Market (2019-2025): Market Forecast by Sectors, by End
User, by Types, by Tank Capacity, by Distribution Channels, by Regions, and Competitive Landscape, s.l.:
Research and Markets.

86 // Decoding Evaporative Air Coolers

Saman, . W., Bruno, F. & Liu, M., 2009. Technical background research on evaporative air conditioners and
feasibility of rating their water consumption: Institute for Sustainable Systems and Technologies

Saman, . W., Bruno, F. & Tay, S., 2010. Technical Research on Evaporative Air Conditioners and Feasibility of
Rating their Energy Performance, s.l.: Institute for Sustainable Systems and Technologies.

Sarkar, J., 2020. Evaporative Cooling Technologies for Buildings, Varanasi: Cooling India.

Sarkar, J., 2020. Layout of active IEC and processes on psychometric chart. Cooling India. Available
at: https://www.coolingindia.in/evaporative-cooling-technologies-for-buildings/#:~:text=In%20the%20
hot%2Ddry%20climatic,undergoes%20a%20composite%20climate%20zone.

Sarkar, J., 2020. Layout of DCE and processes on psychometric chart. Cooling India. Available at: https://
www.coolingindia.in/evaporative-cooling-technologies-for-buildings/#:~:text=In%20the%20hot%2Ddry%20
climatic,undergoes%20a%20composite%20climate%20zone.

Singh, M. & Phore, G., 2020. TERI. [Online] Available at: https://www.teriin.org/sites/default/files/2020-01/
modified-accelerating-the-uptake.pdf

Standards Australia, 2016. Australian Standard Evaporative airconditioning equipment, Strathfield, NSW 2135:
Standards Australia International Ltd.

Sustainable and Smart Space Cooling Coalition, 2017. Thermal Comfort for All - Sustainable and Smart Space
Cooling, New Delhi: Alliance for an Energy Efficient Economy.

Teitelbaum, . E., Jayathissa, P., Mil, C. & Meggers, F., 2019. Design with Comfort: Expanding the psychrometric
chart with radiation and convection dimensions. Energy & Buildings, Elsevier.

Zohuri, B., 2018. Chapter 12 - Heat Exchangers. Physics of Cryogenics, pp. 299-330.

Bibliography // 87
+91 11 40567344, 46635600 | www.aeee.in