Government of India

Ministry of Power
Central Electricity Authority

A oadmap for Flexible Operation of Thermal, Gas and Hydro Power

Stations to acilitate ntegration of Renewable Generation

January 2019

Sewa Bhawan, R K Puram, New Delhi - 110066

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Figures
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Tables
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 Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

Integration of Renewable generation into the Indian electricity grid is a challenge as well as an opportunity.
In anticipation of the changing role of thermal power in the Indian power sector and its crucial role in
making best use of renewable sources, this report has been brought out. Here in, an attempt has been made to
capture the gravity of the situation by analyzing the generation trends expected in 2021-22 based on historic

discovered in low load pilot tests and studies of thermal units.

Under Part I of the report, the implications of large-scale renewable generation integration and the need for

the constraints posed by large-scale integration of renewable generation.

of July, 2021. This is on expected lines due to availability of high wind and solar generation during the
monsoon season in India. Considering daily total demand as per 19th EPS and RE generation as projected,

operation of thermal plant is as low as about 26%.

average day during non-monsoon and the best-case scenario is presented. Next, three steps of coordination

power from pump or battery storage or combination of both and evening peak support from coal-plants
under two-shift operation has been considered. Under Step-3, option of RE curtailment has been explored. It
is found that even though RE curtailment ought to be discouraged in the long run, considering current high
prices of storage technologies around 1% curtailment of renewable energy on annual basis may be allowed

Fortunately, in the Indian context, ramp rates, which are calculated from the hourly renewable and

been conducted exclusively on various size of thermal generating units and a preliminary estimate of the

carried out based on suggested methodology.

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Technology advancements within the power sector are keeping the industry in a state of continuous learning
and adoption. The global community has set an exalted objective of limiting global warming to well below

measures are playing a fundamental role in reaching this goal.

overall power system particularly on the supply side. Similarly, higher and more variable residual loads

become more and more complex for the policy makers, investors and power system operators, it also offers
unprecedented opportunities.

of its GDP by 33 to 35 per cent by 2030 from 2005 level, and to create an additional carbon sink of 2.5 to 3
billion tons of CO2 equivalent. Generating power from renewable sources of energy is of cardinal importance

address large renewable integration in a very short time.

having representation from CEA, NTPC and POSOCO. The terms of reference of the committee are the
following: -

on priority basis.
Develop a road map for implementation of the measures on all India basis.
The committee members include: -
1.
2.
3.
4.
5.
6.

thermal power stations. The minutes of the seven meetings of the committee held on 16th Feb, 23rd Feb,
5th

The current study derives expertise from various divisions of CEA, and studies done by POSOCO, NTPC,

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generation to be accommodated in the grid round the clock. The second objective is to view the situation

be required to run at in future. The third objective is to suggest various combinations of generation which can

objectives:
Grid security
Reliability of generating unit

integration of the same into grid.

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Flexibility:

Flexibility expresses the extent to which a power

system can modify electricity production or consumption in response to variability, expected or otherwise.

RES: Unless mentioned otherwise, the term RES or Renewable Energy Sources has been used to represent

Minimum Load: The minimum load is the lowest possible net load a generating unit can deliver under
stable operating conditions. It is measured as a percentage of normal load or the rated capacity of the unit.
Graphical representation of minimum load is depicted in the chart.

Start-up time:

start-up for power plants is given below:

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Ramp rate: The ramp rate describes how fast a power plant can change its net power during

Minimum Thermal load (MTL):

Thermal:
However, in the context of this report, Gas based power stations are considered a separate category.
lignite-
based ones.

assumptions have been made in the absence of which the modelling becomes too complex and error-prone.

The hourly generation pattern of Hydro, Nuclear and Gas in 2021-22 is a function of the historic pattern
followed by them.
Nuclear, Biomass and Small Hydro power plants are operated as base load in the study.

and generation from all types of sources needs to be anticipated. The national electricity demand for the
year 2021-22 has been collected from 19th EPS. The generation from different technologies in future can be

For part IV of the report, the analysis is based on the capacity of the thermal plant in the year 2021-22 to

For this purpose, the committee has collected data from all individual thermal units in the country to get an

Table 2 List of variables on which data was collected from thermal units in the country

Unit Capacity Boiler make Heat Rate Energy Charge Rate

Age of Unit Turbine Make APC Coal Source
Plant Load Factor Mills Type Minimum Load Ramp Rate

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by each fuel source. Even though quantum of total ramp up done by coal is more it is still running at a
much stable load, in comparison to hydro, due to its larger installed base. ydro is a
major contributor here due to its ability of quick start-stop and quick ramping
 Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

IRP Division, CEA and POSOCO.

The installed capacities for 2021-22 of various sources are given below.

Source: National Electricity Plan (NEP), CEA.

The historic generation data has been scaled as follows:

Solar, Wind, Nuclear & Hydro:

hourly basis for the complete year. The average is then scaled based on the installed capacity in 2021-22.

Gas:
in 2021-22.

Small Hydro, Biomass: Since no reliable data is available for these small renewable sources, straight-
line
considered.

Coal:
hourly generation of other types of sources in a day from the hourly demand of that day.

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The historic generation data has been scaled as follows:

days of the year 2021-22 is given in Annexure I .

As stated earlier electricity demand for the year 2021-22 has been collected from 19th EPS and
generation has been predicted for conventional as well as non-conventional power plant.

A month-wise summary is presented below.

Column 1 represents a month of the year 2021-22.

Column 2 gives the maximum total national demand anticipated in a day of the month.
Column 3 gives the maximum renewable generation in the month.
from other
fuel sources. This usually occurs at the time of peak solar generation.
from other
fuel sources. This usually occurs when solar generation is zero.
Column 6 is the monthly average value of the daily minimum thermal load

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is the worst situation in terms of minimum load operation of thermal power plants.

the BAU scenario is shown in the following chart.

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The following inferences are drawn from the above graph.

RES Generation

Hydro Generation

Gas Generation

Biomass and Small Hydro Generation

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An analysis of the coal ramp rates in the year 2021-22 has been conducted and following maximum values
are observed.

Ramp Down Rate:

Ramp up Rate:

Since 15 minutes’ renewable generation data was not available, the analysis was conducted on hourly basis.

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Therefore, it may be concluded that ramp rates are not a challenge for integration of renewable
generation into Indian grid.

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The study of Indian transmission network was conducted to ensure that there is no constraint in the grid
during integration of renewable generation in the year 2021-22. For the purpose of transmission planning,

local consumption and have been adjusted against demand of the respective states.

11.1 Load Generation Balance: Studies have been carried out for the year, 2021-22.

Generation:
Total installed capacity of all the generation projects expected to be materialized by 2021-22 is about

import has been considered from Bhutan. All India Installed capacity and Peak Demand Expected
at the end of 2021-22 are given in the table below:

Demand:

the demand to be met in Bangladesh and Nepal.

considered for the study of power system.

The dispatches and CUF calculated from the hourly data for the peak load and off-peak load are given in the
table below:

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and above system of the National grid.

respectively.
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integration.

12.1 Hydro Power Plant

12.2 Pumped Hydropower Storage

unique feature, compared to conventional schemes, is that it operates in a dual manner i.e. both as turbine and

a small installed base of these technologies. In fact, development of pumped hydro storage schemes is a

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12.3 Coal Power Plants

however, is not the case in countries having large renewable capacities like Germany. The following graph

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to about 45% of grid connected thermal capacity on that day. This is not the present situation of Indian grid
as most of the state generating companies are not maintaining 55% minimum thermal load. It is therefore
proposed that the similar provision of 55% technical minimum load of thermal units shall be adopted by

12.4 Gas Power Plants

Open cycle gas plants are very suitable for balancing and ramping requirement of the grid because of
their

erefore are

gas.

12.5 Demand Side Management

Time of Day Tariff:

for use of electricity at different time of the day. It means that cost of using one unit of electricity will
be different in morning, noon, evening and night. The provision is currently under examination by the
regulators and would contribute positively towards RE integration when it comes into force.
Open Electricity Market:
2014 would encourage demand side response. Consumers would be able to manage their energy cost

electricity retailer offering the best electricity price plans for their businesses and homes. Consumers

energy management packages.

Demand response from High Voltage industrial consumers: Energy consumption of high voltage
electrical items such as arc furnace, HVAC, compressors, chillers or pumps can be managed in a more

Supply of electricity to agriculture sector by dedicated feeders: Separation of electricity feeders for
agriculture from domestic and industrial load would be a measure in favour of grid security. Separate
feeders would enable servicing of agricultural demand during the hours of high solar generation. This
would enable improved minimum loads for conventional power and greater integration of renewable
energy. An estimate of this opportunity is given below.

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1.
2.
3.
4.

Charging of Electric vehicle when solar generation is available: India has ambitious plans for shifting
public and private vehicles to electricity and reduce its dependence on imported oil. The government has

of e-vehicles. Delhi government has proposed to make 25% of all new vehicle registrations to be electric

Daytime charging of e-vehicles is a measure that needs to be promoted for encouraging integration of
renewable energy and make e-vehicles an even greener mode of mobility.

12.6 Battery Storage

manufacturing in the country. The key areas for energy storage application include:

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It is clear from the above arguments that business as usual generation from fuel sources other than coal will

technically improbable considering high ash content in Indian coal. Hence, the committee is of the opinion
that thermal load on coal units should not go below 35% in worst-case scenario in Indian conditions. This

13.1 Typical Days in future

In order to achieve the above objective, we take up typical days of 2021-22 from a thermal power standpoint

at the right time.

Selection of Typical Days

1.
2.
3.
4.

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13.2 Three Steps of Coordination

RE curtailment is explored, after considering the measures of Step one, with its
corresponding impact on thermal minimum load. An example of the data used in the analysis is given in
Annexure II while the graphs are presented in the following sections.

1. Step I:
2. Step II:

3. Step III: RE Curtailment

13.3 Step I: Hydro & Gas Reallocation

been prepared considering the net water and gas requirement in Hydro and Gas, respectively, equal to their
BAU scenarios.

Reallocation of current Hydro and Pumped Hydro Storage (PHS): India currently has an

ability of PHS technology to absorb power during the afternoon and supply it in the evening and

incentive, two-part tariff etc. Presently many states are utilizing their hydro generation for
meeting their base demand as well as balancing purpose, thus optimizing their system to
avoid deviation charge. Optimization of sub systems does not necessarily lead to optimization

Reallocation of Gas based power:

This situation is due to shortage of gas. The BAU case carries forward a similar behavior in the future.
However, we anticipate that even with limited availability of gas we can run the gas based thermal

on either side of the BAU line.

The typical Gas and Hydro generation curves before and after re-allocation are shown for each of the Typical
Days.

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13.3.1 Step 1: Reallocation of Hydro and Gas on Lowest MTL Day

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13.3.2 Step I: Reallocation of Hydro and Gas on Average Monsoon Day

The average day of monsoon has been derived after superimposing 92 days of June to August months of
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13.3.3 Step I: Reallocation of Hydro and Gas on Average Non-Monsoon Day

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13.3.4 Step I: Reallocation of Hydro and Gas on Best MTL Day

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13.4 Step II: Pump or Battery Storage or combination of both and Two Shift Operation

measures may be adopted on top of the measures of Step-I. These include the following.

1. Pump or Battery Storage or combination of both: In this report, we have assumed a conservative

systems connected to the grid.

2. Two shift operation of small, old and high ECR thermal units:

during the monsoon months of June, July and August for six hours in the evening.

The typical Gas and Hydro generation curves before and after allocation are shown for each of the
Typical Days.

13.4.1 Step II: Pump or Battery Storage and Two Shift Operation on Lowest MTL Day

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13.4.2 Step II: Pump or Battery Storage and Two Shift Operation on Average Monsoon Day

The average day of monsoons has been derived after superimposing 92 days of June to August months of the

13.4.3 Step II: Pump or Battery Storage and Two Shift Operation on Average Non-Monsoon Day

step-II in coordination.

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13.5 Step III: RE Curtailment

energy potential, is emerging as a front-runner in installation of RE based power projects. The provisions
of must-run and feed-in tariffs for RES have made the sector more viable than other fuel sources. In such
a scenario, renewable energy curtailment looks like an aberration from the general policy of govt. of India.
Hence, it may be emphasized that the option of RE curtailment may only be looked upon as a last resort.
Issues such as Grid congestion and power evacuation may alone be considered as tenable reasons for
curtailment of RE.

ith the RES generation data available to us, we have attempted to demystify the issue of RE
curtailment. An important conclusion drawn from the analysis is that with just 1% RE curtailment the burden

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suggested in Step-II, are costly measures as on date. Hence, RES curtailment may be a more viable option.
However, with more capacity addition of RES after 2021-22 and reduction in prices of storage technologies,
the scenario is expected to change.

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Utilization of curtailed renewable generation: If the curtailment of renewable is unavoidable

considering
mentioned below:
Power to Gas to Power: Surplus of RES generation can be used to generate hydrogen from water
electrolysis oxygen generated in this process . As per the
requirement of the system, the hydrogen can be used as primary fuel to generate electricity.
Compressed air energy storage (CAES): .
Installation of pump power plant where water is pumped to a tank or reservoir from where the potential
energy can be recovered later in a hydro turbine.
The issue may also be addressed by maintaining battery or pump storage capacity of 2.5% of daily energy
production at plant level energy be used peak hours.

curtailment of renewable generation. In the analysis, 1% renewable generation curtailment on an annual

basis
from other fuel sources.

13.5.1 Step III: RE Curtailment on Lowest MTL Day

improve from 36 % to 56 % with step -III coordination.

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13.5.2 Step III: RE Curtailment on Average Monsoon Day

The graph on the left is BAU scenario on an average day during monsoon. The graph on the right shows

improve from 52 % to 59 % with step-III coordination.

13.6 Summary of the generation scenarios with different steps of coordination.

hour. All thermal power stations should be usually capable of operation at loads of around
45% to 55%. If

Pump or Battery storage and RES curtailment can come to the rescue of thermal
power.

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13.7 Ramp Rate of Coal Generation on Lowest MTL Day

sources is given in the following chart.

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Both regulated and market-based power systems can ensure appropriate investment in additional power plant

for them. This can be accomplished in regulated market-based power systems by improving energy pricing

and could provide a complementary source of income for power plants that are necessary to the system
but

following heads.
Capital Expenditure (CAPEX) This is the one-time expenditure incurred in the installation of various
equipment required to make the plant capable of low load operation.
Operational Expenditure (OPEX)

cost indicated therein may be treated as being indicative in nature. Actual costs involved will highly depend
on the condition of a particular plant and the prevailing market scenario.

14.1 Capital Expenditure

interventions at unit level. The number and type of interventions required would vary from plant to plant
depending on the age of unit and scope of works.

of around Rs.20 crores for implementation of measures enabling stable operation at 40%
minimum load.

Similarly, an estimate of Rs. 50 crore has been provided by GE for unit 2 of Talcher TPS of NTPC to enable
stable operation at 40% minimum load.

To operate a thermal unit below 40% load requires implementation of measures which will depend on the
unit design type, size, coal quality, historical operation, maintenance, and age of the units. The accumulated

guidance on remaining useful life of critical components, which in turn will guide the scope and extent of

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14.2 Operational Expenditure

Impact of Flexible Operation:

Generally, units are designed to operate on base load condition and all the components are accordingly
designed for certain creep life and certain fatigue life in terms of number of starts. As the operation
regime changes and moves away from base load operation to cycling operation, the component
life is consumed at a faster rate.

14.2.1 Cost due to increase in Net Heat Rate

It has been observed that the extent of deterioration in Net Heat Rate depends on the percentage loading of
units. The estimates in this report are based on combustion engineering boiler design and GE make turbines

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Flexible operation leads to a higher rate of deterioration of plant components. This is observed in increased
failure rate and more frequent replacement of components. The impact on reduction in life of components
increases with increase in number of start stops the unit undergoes in a year. As a result, the operation and

Intertek, USA at Ramagundam TPS and Jhajjar TPS of NTPC. The study was based on
the ten-year historical

unit have not been carried out.

The above costs are based on the cycling cost studies of two units of NTPC. It is anticipated that as
these costs are based on the past cycling, which has not been very severe, they are expected to rise with
increase in cycling and age and condition of units.

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14.2.3 Cost due to Increased Oil Consumption due to frequent start/ stops.

The quantity of oil consumption depends on the duration of startup. The level of oil consumption for startup

14.2.4 Summary of perational Costs

A summary of the is presented The overall

impact due to different modes of cyclic operations .

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plants, which may have been built to operate round the clock. Power plants can provide different modes of
 Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

16. Scheduling of Thermal Power

Methodology:
slowness of the process of combustion and time required to achieve required steam parameters. Therefore,

operator is not possible.

Hence, entire day’s scheduling be done based on the forecasted value of maximum evening
to
run at low loads during the hours when high solar power is available and then they would be expected to
ramp up gradually when solar generation goes down and total demand picks up. An illustration is given
on the right above.

Analysis

The number of units scheduled from each category are calculated. Possible values of minimum load the units
are expected to run at is estimated.

given below. The category TSO would be used in Two Shift operation as detailed in .

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The scheduling of units has been done based on ECR data collected from .
All India Unit-level data
respective state merit order etc. Based on the data, the analysis of
technical capability data of the All India

16.1 Lowest MTL day – Case study

same as those explained in the section on coordinated effort.

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Further, Units having higher ECR are proposed to run at lower loads than units having lower ECR within the
same category in the table below:

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16.2 Average Monsoon Case

The demand met from coal generation in the average monsoon case is given below.

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Note: The scheduling has been envisaged considering the result of pilot test and studies of thermal units

for optimum scheduling of various sizes of thermal units may be done using a modelling software.

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of operation, maintenance and administration. Some of the measures required are listed below.

initiate training programs accordingly. The commercial impacts must also be sensitized.

Check the status of the plant

Ensure smooth operation of all control loops at base load.

Plan and execute test runs

Create transparency about the plant performance with respect to normal load, start-up and cycling
behavior in the current setup.

Identify constraints and process limitations as well as improvement potential.

Optimize I&C system:

level of automation is a prerequisite for tapping this potential.

Optimization of underlying control loops, i.e. coal supply, drum level and air control, is a basic
requirement and plant operators need to consider interlocks coming from logics.

Implement mitigation measures

layup procedures as well as on maintenance strategies. The use of appropriate condition monitoring
systems is essential.

Optimize combustion: Stable combustion is the key aspect to ensure minimum load operation. The
following aspects are important

Transparency about the coal quality and composition

Operation with a reduced number of mills

Adaptation of the boiler protection system at low load operation.

Optimize start-up procedures:

check start-up related temperature measurements and consider replacement of measuring equipments, if
required. Besides automated start-up procedures, this is a prerequisite to assess admissible temperature
limits and to operate with less conservative set points.

This refers to the measures

components, e.g. ID, FD and PA fans or feed water pumps.

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9. Improve the coal quality: Better quality of coal improves the combustion process. Therefore, implement

10. Automate Control Procedures: Automated operation always has advantage over manual operation.
Some of the options that can be explored are:

Automated Start of Fans and Pumps

Steam Temperature Control

Flue Gas Temperature Control

The test procedure of the pilot test is attached at annexure-I for reference of the generating utilities.

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been reiterated by the Commission in several documents and orders.

generators, slow tertiary frequency control as an ancillary service for manually changing the schedules of

brought out the need for automatic secondary frequency control in the Indian grid.

Almost every day it is observed that the inter-state shared generating stations have power reserves available
due to non-requisition by the states. Some generators are under reserve shutdown due to less requisition of

18.2 AGC on Solar/Wind

Considering the excellent controllability of power electronic devices and the low cost of the A
AGC. This would be
useful for regulation in extreme dispatch scenarios like run out of secondary
forecast can
be together used for deciding the participation of renewables under AGC for a particular time of the day.
In the normal operation, the renewables would be dispatched fully. However, in cases of either
levels, it
might be desirable to curtail RE through down regulation which can be done quickly through AGC signals.
This process would also bring in transparency in RE curtailment.

18.3 Reserve Regulation Ancillary Services(RRAS)

RRAS Regulation ‘Up’ service. The RRAS Regulation ‘Down’ service is provided by these generating stations

Probability High Impact Events. Thus, RRAS will help in facilitating large scale integration of renewables.

18.4 Fast Response Ancillary Services(FRAS)

Hydro generators are suitable for providing fast response and peaking support. Fast Response Ancillary

stations e.g. to handle the hour-boundary frequency spikes. . In this direction, CERC, vide order in Petition

all Central sector hydro generating stations which would help in gaining experience. POSOCO has been

declared by the hydro stations shall be honored and the total energy delivered over the day would be
maintained as declared by the hydro station.

18.5 Usage of retiring power plants as synchronous condensers:

grid can be affected adversely in future due to reduction of

rotating generating capacity in the power system. Solar PV panels have no rotating parts and no
mechanical inertia. The retirement of a conventional power
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units as synchronous condensers for supplying reactive power as well as short circuit support.

Reactive power: Reactive power shortages are caused by a variety of factors: plant retirements, plant trips,
transmission line failures and peak electricity demand. Reliable sources of reactive power, like synchronous

balanced, the result can lead to system voltage instability, islanding, voltage collapse and, ultimately it leads
to system breakdown.

Short circuit support: As the condenser is a rotating device, it can also provide short circuit support in
addition to reactive power capacity. Conversion of thermal generating unit to a synchronous condenser can
provide electrical system voltage support resulting in a stable source of electric power.

Converting an existing synchronous generator to a synchronous condenser requires a custom-engineered

solution because each plant will have a unique design and layout. The generator, electrical, cooling and
lubrication systems must be evaluated as a whole. A plant level study needs to be done for the detailed

mode of operation.
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19.1 Conclusion

economically unviable for coal units to operate at such low loads especially with the high-
ash Indian coal. In step one, with additional peaking support from hydro and gas, the
minimum loads of coal

Finally, as a last resort, RE curtailment is explored with its corresponding impact on thermal minimum

from other fuel sources. Alternatively, provision for storage of 2.5% of daily energy production at plant
level by RE generator and utilization of same during peak demand hours will strategically minimize the

charging load is coordinated with the time of solar generation.

Flexible operation of smaller sized thermal unit is economical than that of bigger sized units. Thus, it is
proposed to run smaller size units at lower load and bigger size unit at comparatively higher load during low
grid demand or high solar generation period when the lower sized unit has equal or lower ECR compared
to the higher sized unit. Investment is required to implement various measures, which may vary from plant

have to work on this aspect. Regulatory intervention is also required for mandatory establishment of storage

19.2 Recommendations

1.
operated hydro plants would play an important role in re-allocation of hydro generation. Pumped
storage, existing and under-construction, may be used exclusively for peaking or balancing of system

lucrative, provision of two-part tariff and revision of grid code are suggested. Regulatory intervention is
required to implement the recommendation.

2.

the report.

3. Establishment of pump or battery storage or combination of both at strategic locations may be explored
for energy storage during high solar generation period and utilizing the same during peak demand

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hours or at the time of need.

cannot be avoided in the year 2021-22, especially during the monsoon period. It is suggested that

such geographical advantages are available in India. For others, mandatory establishment of battery
storage of 2.5% of daily energy generation at solar or wind plants is suggested. Regulatory intervention
is required to implement the same.

operation decreases with decreasing unit size. Therefore, it is suggested to operate smaller sized units,

higher sized unit.

ECR, should be given preference over other units in terms of generation schedule.

measures need to be undertaken to make the plants capable of low load operation. From the cost point

as below.

Capex to be reimbursed on actual basis after examination.

Pilot study of thermal units for operation at low load shall be conducted before implementation of

plant operators becomes an important measure in the changing operational regime. Therefore, training
programs on thermal power plant simulator should be institutionalized focusing on areas such as plant

situations and safety procedures.

Demand side management including measures targeted at domestic, agricultural, industrial and e-mobility
sectors would enable more rational consumption pattern of electricity, which would facilitate integration
of renewable generation. All these measures are recommended to increase power consumption during

available.

60
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

Annexure 1: Data
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

Annexure I
1. Minimum Thermal Load (MTL) is calculated such that all fuel sources operate as business-as-usual
(BAU) and all thermal units ramp up / ramp down at the same rate simultaneously. The critical day
obtained in this fashion is 27th July 2021.

2. 10% reserve has been considered. As APC deteriorates with low load operation, APC of 7% at
maximum load and 9% at minimum load is considered.

01-Apr 192082 73165 74458 139302 49.16%

02-Apr 194439 70102 80139 141357 52.14%
03-Apr 192709 71682 75651 141000 49.35%
04-Apr 194328 73660 72786 140815 47.54%
05-Apr 191361 71878 72780 140151 47.76%
06-Apr 193765 71884 75273 142192 48.69%
07-Apr 194971 68924 81076 146234 51.00%
08-Apr 194211 70784 81432 144886 51.70%
09-Apr 194980 69683 82393 148366 51.08%
10-Apr 193482 69800 82543 147452 51.49%
11-Apr 192989 74200 78995 146120 49.73%
12-Apr 189577 70602 73670 142471 47.56%
13-Apr 189062 69080 74725 142784 48.14%
14-Apr 189788 66604 82009 146995 51.31%
15-Apr 194432 63471 86970 149962 53.34%
16-Apr 197485 66361 83486 153321 50.08%
17-Apr 192760 66220 81524 150051 49.97%
18-Apr 194552 69872 78759 148998 48.62%
19-Apr 194604 81274 65863 146917 41.23%
20-Apr 194781 69908 79145 149526 48.68%
21-Apr 198294 63698 88254 152204 53.33%
22-Apr 198717 65181 87740 149881 53.84%
23-Apr 197399 71834 81643 146238 51.35%
24-Apr 195553 72104 78396 145246 49.64%
25-Apr 196598 74277 76577 143604 49.05%
26-Apr 194715 68149 79841 144168 50.94%
27-Apr 197248 60510 90071 146945 56.38%
28-Apr 197954 68988 86026 146872 53.87%
29-Apr 199528 71503 83721 147443 52.23%
30-Apr 198499 76378 77609 145949 48.91%
01-May 194191 76343 72826 144695 46.29%
02-May 196217 78996 75377 144148 48.10%
03-May 193164 78218 71848 142912 46.24%
04-May 191111 76637 74038 142013 47.95%
05-May 194130 75836 75716 143853 48.41%

Page 1 of 9 Annexure I
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

06-May 196940 77049 76623 146312 48.17%

07-May 198349 72691 79920 145464 50.53%
08-May 190838 68509 83756 143186 53.80%
09-May 196128 67993 83920 137457 56.15%
10-May 191906 74215 74518 139422 49.16%
11-May 193990 79441 70420 138958 46.61%
12-May 196924 75424 75231 145098 47.69%
13-May 193044 77745 72840 143680 46.63%
14-May 194699 76290 70998 145121 45.00%
15-May 193837 73526 74454 144039 47.54%
16-May 195198 78488 72963 142910 46.96%
17-May 192708 78411 70704 141576 45.93%
18-May 193562 73563 76234 139913 50.12%
19-May 193396 85806 66713 135934 45.14%
20-May 197863 86085 65143 140630 42.61%
21-May 199364 88416 65319 134032 44.82%
22-May 199811 91723 60964 134426 41.71%
23-May 196273 92496 61706 131182 43.27%
24-May 195028 87332 60624 131698 42.34%
25-May 191855 90115 61074 126539 44.39%
26-May 198715 87083 66188 137605 44.24%
27-May 198148 87249 68619 142834 44.19%
28-May 198527 90210 63715 141704 41.36%
29-May 195640 90339 59368 138550 39.41%
30-May 197113 83564 69466 140781 45.38%
31-May 193160 88519 62555 134936 42.64%
01-Jun 193438 85686 65117 137074 43.69%
02-Jun 196732 81121 75287 141243 49.03%
03-Jun 196413 72890 82703 141365 53.81%
04-Jun 199590 71587 84695 145676 53.48%
05-Jun 197510 72612 82198 149471 50.58%
06-Jun 202618 76439 81641 146260 51.34%
07-Jun 197098 76088 79071 144487 50.34%
08-Jun 201416 79859 76733 141265 49.96%
09-Jun 200369 81903 74892 135480 50.84%
10-Jun 201201 81706 76652 133852 52.67%
11-Jun 197970 72423 85601 138336 56.92%
12-Jun 194130 84964 68269 134289 46.76%
13-Jun 193112 95654 55591 126881 40.30%
14-Jun 195355 94784 51094 128200 36.66%
15-Jun 196702 95349 54018 133459 37.23%
16-Jun 202178 88225 64268 140881 41.96%
17-Jun 203173 87322 69553 140585 45.51%

Page 2 of 9 Annexure I
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

18-Jun 202614 84205 72874 140244 47.79%

19-Jun 201605 92558 61967 139375 40.89%
20-Jun 203001 91606 62493 131382 43.75%
21-Jun 196022 94470 53682 125772 39.26%
22-Jun 199133 102839 43849 123755 32.59%
23-Jun 198817 97386 52575 123267 39.23%
24-Jun 199015 104369 45343 119298 34.96%
25-Jun 197881 105715 40589 124800 29.91%
26-Jun 199810 105670 40938 123614 30.46%
27-Jun 201470 103307 47621 120105 36.47%
28-Jun 200428 99387 49442 126912 35.83%
29-Jun 197982 99660 52560 124293 38.90%
30-Jun 205164 100115 52712 136106 35.62%
01-Jul 201723 108926 45763 126077 33.39%
02-Jul 200912 99571 49949 121804 37.72%
03-Jul 197787 106365 41241 119615 31.71%
04-Jul 202529 108484 41717 119972 31.98%
05-Jul 200939 107415 42198 121228 32.02%
06-Jul 198890 108036 41372 121007 31.45%
07-Jul 202379 105542 48929 121243 37.12%
08-Jul 203396 105614 51208 124166 37.93%
09-Jul 200979 108395 44953 122625 33.72%
10-Jul 195144 107069 41351 119427 31.85%
11-Jul 197643 105907 44181 127614 31.84%
12-Jul 196034 97533 49122 124338 36.34%
13-Jul 199099 86441 62404 126026 45.54%
14-Jul 203374 85197 66679 129603 47.32%
15-Jul 202481 93535 59353 128928 42.34%
16-Jul 199450 96111 50247 127670 36.20%
17-Jul 194534 92799 52814 121782 39.89%
18-Jul 194790 105137 41455 117802 32.37%
19-Jul 194645 108316 34071 113695 27.56%
20-Jul 196607 105000 38910 121594 29.43%
21-Jul 201041 102262 46383 124087 34.38%
22-Jul 199961 102318 45254 121877 34.15%
23-Jul 198795 102692 42854 120364 32.75%
24-Jul 196390 95438 48447 120500 36.98%
25-Jul 197300 100021 45455 122440 34.15%
26-Jul 193252 95777 47052 120800 35.83%
27-Jul 190480 108082 32665 116769 25.73%
28-Jul 195634 103845 37605 121781 28.40%
29-Jul 195959 103795 37348 115504 29.74%
30-Jul 197121 96133 45044 123157 33.64%

Page 3 of 9 Annexure I
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

31-Jul 194280 88674 49472 120550 37.75%

01-Aug 193299 83683 55165 121710 41.69%
02-Aug 192388 82006 55089 120000 42.22%
03-Aug 196715 96844 45525 118068 35.47%
04-Aug 197621 101046 42447 119379 32.70%
05-Aug 199307 96917 45837 121903 34.59%
06-Aug 200245 95083 49456 128680 35.35%
07-Aug 198076 93943 48954 126147 35.69%
08-Aug 200568 88419 56358 129493 40.03%
09-Aug 198734 82166 61316 131961 42.74%
10-Aug 195324 82683 58766 129079 41.87%
11-Aug 199524 84733 58550 129672 41.53%
12-Aug 198791 84778 57030 127897 41.01%
13-Aug 198193 86770 53363 123910 39.61%
14-Aug 197494 88451 52265 123269 39.00%
15-Aug 189474 91355 37897 119009 29.29%
16-Aug 197298 87401 49613 128375 35.55%
17-Aug 198460 74333 64180 134579 43.86%
18-Aug 197583 71272 68873 135925 46.61%
19-Aug 202552 73332 70665 136313 47.68%
20-Aug 205697 76191 71001 138195 47.26%
21-Aug 205109 76341 70634 137765 47.16%
22-Aug 207042 80102 68184 135792 46.18%
23-Aug 205333 81469 67665 130302 47.76%
24-Aug 204332 79459 71947 137271 48.21%
25-Aug 206200 81133 71192 136195 48.08%
26-Aug 207558 81241 73373 135576 49.78%
27-Aug 206247 79963 72519 139890 47.68%
28-Aug 204781 80387 72446 140967 47.27%
29-Aug 202349 79309 71535 136752 48.11%
30-Aug 204044 81937 68284 134912 46.55%
31-Aug 201127 76659 67884 136162 45.86%
01-Sep 201308 72885 72037 139203 47.60%
02-Sep 200743 71231 75913 140082 49.84%
03-Sep 202396 68167 78251 146096 49.26%
04-Sep 196782 69252 74899 134548 51.20%
05-Sep 196116 74118 71001 135898 48.05%
06-Sep 198395 71213 74989 138689 49.73%
07-Sep 199727 62215 84931 144259 54.15%
08-Sep 205698 62986 88122 144972 55.91%
09-Sep 207876 69217 85212 144262 54.33%
10-Sep 207581 65907 88496 147602 55.15%
11-Sep 207447 67453 86681 146139 54.56%

Page 4 of 9 Annexure I
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

12-Sep 207489 66398 90152 145859 56.85%

13-Sep 206744 67075 87638 140245 57.48%
14-Sep 204059 72454 82555 135881 55.88%
15-Sep 205562 66523 87411 136849 58.75%
16-Sep 205884 75176 79802 136430 53.80%
17-Sep 204459 72903 79224 133412 54.62%
18-Sep 202295 75959 77300 131120 54.22%
19-Sep 206725 77500 75145 140782 49.09%
20-Sep 201499 80771 70462 135875 47.70%
21-Sep 202756 70612 77678 138430 51.61%
22-Sep 204049 60028 88405 144450 56.29%
23-Sep 205573 57662 91979 150382 56.26%
24-Sep 205107 56199 94943 151101 57.79%
25-Sep 202551 58047 91014 146781 57.03%
26-Sep 207004 60481 92197 152205 55.71%
27-Sep 202795 58970 90896 150198 55.66%
28-Sep 204872 49322 104329 154821 61.98%
29-Sep 209907 56336 101333 157679 59.11%
30-Sep 208099 58379 100884 156774 59.19%
01-Oct 206818 54149 106450 159128 61.53%
02-Oct 201786 50113 103096 153627 61.72%
03-Oct 206851 54587 103380 150267 63.28%
04-Oct 208426 56998 102617 157215 60.04%
05-Oct 207997 51191 108391 159902 62.35%
06-Oct 211819 52830 107438 158274 62.44%
07-Oct 225751 52421 119610 175611 62.65%
08-Oct 209826 52232 107134 156976 62.77%
09-Oct 207095 55773 100767 155984 59.42%
10-Oct 206506 62580 94310 147712 58.73%
11-Oct 200999 54259 99127 150087 60.75%
12-Oct 201516 52215 102867 154526 61.23%
13-Oct 207067 55892 102025 158176 59.33%
14-Oct 206309 55540 99133 157085 58.05%
15-Oct 206950 54313 100833 157895 58.74%
16-Oct 205542 54661 101552 156358 59.74%
17-Oct 207902 55459 103047 160367 59.10%
18-Oct 205652 58364 98926 156765 58.04%
19-Oct 207778 53040 107146 161071 61.18%
20-Oct 210372 54643 106764 163089 60.21%
21-Oct 210259 53170 109524 161281 62.46%
22-Oct 202829 53225 104154 158037 60.62%
23-Oct 199211 50326 107338 155905 63.33%
24-Oct 200094 54255 102882 151108 62.62%

Page 5 of 9 Annexure I
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

25-Oct 198011 54118 101336 150492 61.93%

26-Oct 200976 51862 103857 155372 61.48%
27-Oct 203569 52944 105986 158860 61.36%
28-Oct 201486 54629 103603 156700 60.81%
29-Oct 200693 52044 103833 157175 60.76%
30-Oct 194639 53000 99911 150658 61.00%
31-Oct 195762 52243 99196 148818 61.31%
01-Nov 193237 52301 100193 149084 61.81%
02-Nov 196113 48850 104433 153722 62.49%
03-Nov 201216 53496 103557 155573 61.23%
04-Nov 200234 53460 104246 155171 61.79%
05-Nov 201763 55564 102890 154243 61.36%
06-Nov 199214 54445 103335 154427 61.55%
07-Nov 200257 57873 101585 156651 59.65%
08-Nov 199075 59510 100887 152691 60.77%
09-Nov 198421 59759 99393 148259 61.66%
10-Nov 199352 62485 93678 145539 59.20%
11-Nov 195147 71101 82151 141728 53.31%
12-Nov 193719 54160 97967 149866 60.13%
13-Nov 192085 55678 96368 149407 59.33%
14-Nov 194742 67736 85228 148283 52.87%
15-Nov 192886 59715 92965 150479 56.82%
16-Nov 193583 68442 85361 151659 51.77%
17-Nov 194824 51565 104625 152619 63.05%
18-Nov 196201 67526 88136 149608 54.19%
19-Nov 196049 63475 90872 149286 55.99%
20-Nov 192115 60887 94607 148128 58.75%
21-Nov 196646 63339 93248 150438 57.01%
22-Nov 187647 61192 93784 147047 58.66%
23-Nov 194985 58105 95252 153314 57.14%
24-Nov 195339 59446 99424 153329 59.64%
25-Nov 194921 56196 98631 153415 59.13%
26-Nov 195702 60555 93701 151891 56.74%
27-Nov 191131 53776 100135 148515 62.02%
28-Nov 195814 53679 102857 152135 62.19%
29-Nov 193217 57604 97851 151306 59.48%
30-Nov 192495 61039 93941 150956 57.24%
01-Dec 193049 59522 96969 154058 57.89%
02-Dec 193052 64012 91574 154062 54.67%
03-Dec 193281 61710 92829 152390 56.03%
04-Dec 189502 65613 87970 148129 54.62%
05-Dec 194399 65683 91760 148088 56.99%
06-Dec 190157 75992 80311 142547 51.82%

Page 6 of 9 Annexure I
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

07-Dec 193847 66088 93494 150518 57.13%

08-Dec 197050 64011 94256 153138 56.61%
09-Dec 198739 58270 103180 155841 60.90%
10-Dec 196925 63004 99329 154416 59.17%
11-Dec 194259 67807 90541 152111 54.75%
12-Dec 193097 62833 95568 153463 57.28%
13-Dec 188711 57253 99000 149861 60.76%
14-Dec 189377 65358 90594 150109 55.51%
15-Dec 193080 64681 91226 149757 56.03%
16-Dec 194808 70730 86834 149838 53.30%
17-Dec 194685 71000 87313 153498 52.32%
18-Dec 190121 62974 96542 152267 58.32%
19-Dec 195665 59613 103163 152934 62.04%
20-Dec 192755 63777 95507 151716 57.90%
21-Dec 194320 63389 97297 153708 58.22%
22-Dec 198987 65027 98531 158497 57.18%
23-Dec 198277 62216 101213 155712 59.79%
24-Dec 197100 62302 100658 154624 59.88%
25-Dec 192103 70936 89497 148450 55.45%
26-Dec 196954 73137 90594 150570 55.34%
27-Dec 193909 75176 86690 148602 53.66%
28-Dec 194866 81751 81835 147123 51.16%
29-Dec 197112 82185 82861 150421 50.67%
30-Dec 198382 72306 91261 147616 56.86%
31-Dec 196168 83154 80071 144561 50.95%
01-Jan 188664 81285 79493 140270 52.13%
02-Jan 195603 69847 92423 154627 54.98%
03-Jan 193238 67750 93097 155319 55.13%
04-Jan 194203 68932 94227 153859 56.33%
05-Jan 198368 74880 90890 159196 52.51%
06-Jan 199422 69864 96114 160059 55.23%
07-Jan 198127 69937 92329 159516 53.24%
08-Jan 195530 66135 94184 157929 54.85%
09-Jan 198083 71440 92127 158310 53.53%
10-Jan 196525 67863 94151 154291 56.13%
11-Jan 198771 70459 94307 156427 55.45%
12-Jan 201091 73286 93093 158198 54.13%
13-Jan 199162 73780 91265 159365 52.67%
14-Jan 190953 75210 84346 147283 52.67%
15-Jan 190015 76102 84285 144941 53.49%
16-Jan 194235 72916 90658 152251 54.77%
17-Jan 195873 72794 90992 155774 53.73%
18-Jan 198499 70231 95589 158527 55.46%

Page 7 of 9 Annexure I
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

19-Jan 198605 74395 92447 157269 54.07%

20-Jan 200434 70041 95590 156614 56.14%
21-Jan 202651 71925 92329 160862 52.79%
22-Jan 198656 72001 91630 156341 53.91%
23-Jan 201187 67989 97093 154520 57.79%
24-Jan 198155 70946 94043 154883 55.85%
25-Jan 197525 76860 87087 152216 52.62%
26-Jan 189047 75485 80425 138902 53.26%
27-Jan 198222 75991 83623 150931 50.96%
28-Jan 200527 74823 89381 155283 52.94%
29-Jan 196736 64884 98126 152216 59.29%
30-Jan 200235 76228 89207 156150 52.55%
31-Jan 197073 75571 89552 154130 53.44%
01-Feb 197730 68540 95829 154304 57.12%
02-Feb 200233 74816 89455 148672 55.34%
03-Feb 200364 74701 88842 154133 53.02%
04-Feb 201622 82015 81150 149265 50.01%
05-Feb 197420 74291 87643 151585 53.18%
06-Feb 199673 73149 90292 152309 54.53%
07-Feb 197570 70974 91984 151035 56.02%
08-Feb 198077 79724 84325 151089 51.33%
09-Feb 203259 74369 88909 154026 53.09%
10-Feb 202748 79046 87072 154633 51.79%
11-Feb 200769 70990 91692 156955 53.73%
12-Feb 199066 68657 94054 157536 54.91%
13-Feb 202838 71843 93117 156985 54.56%
14-Feb 200140 65092 99622 159219 57.55%
15-Feb 199910 66734 99300 155484 58.74%
16-Feb 202369 70317 94924 157556 55.41%
17-Feb 201832 72450 92112 157855 53.67%
18-Feb 202280 69969 96513 158747 55.92%
19-Feb 200899 68198 97624 155505 57.74%
20-Feb 203094 67883 95514 157142 55.91%
21-Feb 199735 74339 87212 153380 52.30%
22-Feb 200436 73071 92201 155683 54.47%
23-Feb 205811 75230 90723 155506 53.66%
24-Feb 206484 78427 89984 153419 53.95%
25-Feb 206012 73974 93439 158868 54.10%
26-Feb 201223 68365 97219 155226 57.61%
27-Feb 205525 64942 101933 161981 57.88%
28-Feb 199774 72894 94218 153172 56.58%
01-Mar 194645 73192 84304 147682 52.51%
02-Mar 199123 74122 84126 150339 51.47%

Page 8 of 9 Annexure I
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

03-Mar 199991 70355 92305 155407 54.63%

04-Mar 198135 67001 95481 157003 55.94%
05-Mar 193738 70476 89381 152273 53.99%
06-Mar 188377 70435 79324 144478 50.50%
07-Mar 192325 68859 88172 147063 55.15%
08-Mar 195373 64754 91865 146534 57.66%
09-Mar 199007 75316 84709 149235 52.21%
10-Mar 194368 74849 84075 144698 53.44%
11-Mar 195989 74353 83655 144223 53.35%
12-Mar 192602 70179 86341 140579 56.49%
13-Mar 185585 74684 73474 140192 48.21%
14-Mar 193897 71204 84725 143405 54.34%
15-Mar 191697 69151 84353 145626 53.28%
16-Mar 196454 65714 90988 152538 54.86%
17-Mar 198523 68859 89451 153300 53.67%
18-Mar 198752 70827 87912 154034 52.49%
19-Mar 196543 65838 94297 153523 56.49%
20-Mar 198477 68694 91356 155024 54.20%
21-Mar 201498 70917 90709 157639 52.93%
22-Mar 200848 66491 96597 155796 57.03%
23-Mar 202965 68666 96358 154126 57.50%
24-Mar 201722 70726 91413 154202 54.53%
25-Mar 206297 68780 96856 160561 55.48%
26-Mar 203421 66986 99974 157978 58.21%
27-Mar 204515 71018 94057 157033 55.09%
28-Mar 206749 70647 97170 159116 56.17%
29-Mar 202653 71733 93174 157860 54.29%
30-Mar 206216 65481 98809 160104 56.76%
31-Mar 206474 63019 103350 161301 58.93%

Page 9 of 9 Annexure I
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

Annexure
 Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

Assumptions

1. Cost due to increase in Heat Rate and Auxiliary Power Consumption (APC)

Assumptions in calculation of per unit cost are as follows.

For Significant Load Following, the calculations are mentioned in Tables 16 to 18.
The unit running as daily start-stop would remain either at zero load or at full load during its
operation in a day of the year. As such, for Daily Start, the net heat rate deteriorates by 3.8% &
6.3% for 200 MW & 500 MW unit resp.
The unit running as weekly start-stop would be required to flex during a day as per requirement
in addition to its weekly shutdown routine. As such, for Weekly Start, the net heat rate
deteriorates by 11.6% & 13.8% for 200 MW & 500 MW unit resp.
The base ECR has been assumed to be 200 paisa/kWh based on the average ECR of NTPC
stations from April to October 2018

2. Cost due to increase in Operation and Maintenance (O&M) due to reduction in life of
components

Assumptions in calculation of per unit cost are as follows.

2.1 The increase in O&M cost due to load following on per unit basis is calculated as per the following
formula.

n = 6, number of weeks of planned and forced outages per year.

k = 2, number of significant load followings considered per day.
O&M Costevent = 0.5 INR lakhs for 200 MW and 2.7 INR lakhs for 500 MW, increase in O&M cost
due to one event of significant load following as given in Table 19.
PLF is 63% for units operating under Significant load following.

2.2 The increase in O&M cost due to Daily and Weekly Start on per unit basis is calculated as per the
following formula.

Six weeks of planned and forced outages per year.

Daily Start: Total no. of starts are 81 where the ratio of cold (nc), warm (nw) and hot (nh) start is
1:4:2. Units are operated for six hours in the evening during a day for three monsoon months of
the year.
Weekly Start: Total no. of starts are 46. All are cold starts (nc). Units are flexed as per
requirement of grid in addition to weekly shutdown. PLF is 45%.

Page 1 of 2 Annexure III

 Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

3. Cost due to increase in Oil consumption on account of frequent start/ stops

Assumptions in calculation of per unit cost are as follows.

The increase in oil cost due to cycling on per unit basis is calculated as per the following formula.

Six weeks of planned and forced outages per year.

Daily Start: Total no. of starts are 81 where the ratio of cold (nc), warm (nw) and hot (nh) start is
1:4:2. Units are operated for six hours in the evening during a day for three monsoon months of
the year.
Weekly Start: Total no. of starts are 46. All are cold starts (nc). Units are flexed as per
requirement of grid in addition to weekly shutdown. PLF is 45%.
Oil Costevent = As given in Table 20. Cost of oil is 45000 INR/kl.

Page 2 of 2 Annexure III

Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
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Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

Minutes of the meeting held on 8th February 2018 on Task Force Committee Report
on Flexibilisation of Thermal Power Plants
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

List of participants.
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

Minutes of the meeting of the committee on Flexibilisation of Thermal Power Plants

held on 16th February 2018
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

List of participants.
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

e
region and Tertiary reserves should be maintained in a de-centralized fashion by each state
control area for at least 50% of the largest generating unit available in the state control area.
This would mean secondary reserves of 1000 MW in Southern region; 800 MW in Western
regions; 800 MW in Northern region; 660 MW in Eastern region and 363MW in north-eastern
region. (total approx. 3600 MW on an All India basis). Primary reserves of 4000 MW would
be maintained on an All India basis considering 4000 MW generation outage as a credible
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

1. CE (TPRM) welcomed the participants to the 7th meeting of the committee on Flexibilisation
of Thermal Power Plants and highlighted that pilot power project demonstration, identification
of units, transmission constraints, and economic / commercial analysis is the next step in the
study. He also congratulated NTPC for successful demonstration of 40% minimum load
operation at Dadri TPS, Unit 6.
2. Regarding pilot demonstration at Dadri TPS, unit 6, NTPC was requested to share its learnings,
test procedures, SOPs for guidance of the utilities.
3. An issue was raised by AGM, NTPC on operation of thermal plants equipped with FGD at
reduced loads. It remains a cause of concern whether FGD equipment will be able to perform
efficiently when the unit is running at low loads. In addition, upto what minimum load of the
TPS the performance of FGD will be called satisfactory.
4. Members discussed the matter of low load operation of TPS highlighting that the measures to
be implemented (automation etc.) for minimum load operation would require at least Rs. 10 to
15 Cr investment per unit. After detailed deliberation members agreed that the funding
opportunity for implementation of minimum load operation can be explored from PSDF, as it
is a matter of Grid security and stability. Further, funding option can also be explored from
Coal Cess Fund as investment in this regard is enabling integration of clean energy i.e. RES
directly.
5. Regarding flexibilisation from sources other than thermal:-
a. Members expressed hope that battery storage may become viable in coming years and
may be helpful in reducing the burden of RES integration on thermal power stations.
b. Members also expressed that modifications in approach towards distribution of Gas
may be required in order to employ Gas based power stations in flexible operation.
6. Members also emphasized that training of power plant personnel / operators on simulators and
education on automation etc. would be essential for operation of thermal units at low load.

The meeting ended with a vote of thanks to the Chair.

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Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation

1. Shri B C Mallick, Chief Engineer, TPRM, CEA

2. Shri Rajeev Kumar, Director, TPRM, CEA
3. Shri Rakesh Kumar, Director, HPP&I, CEA
4. Shri Vikram Singh, Director, GM, CEA
5. Smt. P. E. Kamala, DD, IRP, CEA
6. Shri Prabhjot Singh Sahi, DD, TPRM, CEA
7. Shri N. Nallarasan, AGM, POSOCO
8. Shri A.K.Sinha, AGM, NTPC
9. Shri Nathi Ram, Manager, NPTC
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation
Central Electricity Authority Flexible Operation Of Thermal Plant For Integration Of Renewable Generation