EE5053: Energy Efficiency, Demand Management and Conservation
Tutorial 1: Relevance of Energy Efficiency and Energy Intensity
1. Explain what is meant by “energy intensity” of a manufacturing industry. What
are the “energy intensive” manufacturing industries in Sri Lanka? Describe
explaining the different forms of energy used in these industries, energy intensive
manufacturing operations, and the energy-related issues faced by them.
2. Sri Lanka energy balance for 2015 is attached, both in terms of original
commodity units and in terms of tonne of oil equivalent.
Visit the Central Bank website www.cbsl.gov.lk or refer the Central Bank Annual
Report for 2015 and obtain/calculate the gross domestic product for year 2015.
Calculate the energy intensity of the Sri Lanka economy in terms of TOE/million
LKR and TOE/million USD, for primary energy as well as for commercial energy.
3. Energy prices in Sri Lanka are said to be high compared with the countries
competing with Sri Lanka to attract new industrial investments as well as to retain
and expand existing industries. Furthermore, it is often argued that it is the
manufacturing industry, which requires reliable and lower cost energy, that adds
significant value to our economy. Discuss this issue by conducting suitable
analyses of industrial data from national accounts and any other information
available from industries.
4. Describe the different forms of energy used worldwide, available fossil fuel
reserves, and the potential of using these different sources in Sri Lanka. Include
the costs and environmental impacts of the different resources, and the need for
diversification of energy sources in the country’s drives towards industrial
development.
5. An industrialist or a service provider comes to you complaining his energy
costs are too high, and that the business may even collapse if this problem is not
addressed immediately. How would you assist him to identify the energy problem
and resolve the issue in a systematic manner?
6. Figure Q6a shows the actual profile of energy intensity of the economy in Sri
Lanka, while Q6b shows published information from a few other countries.
Comment on how Sri Lanka’s economy and energy sector are performing with
regard to energy intensity. What are the shortcomings of this analysis ?
EE5053 Tutorial 1 1
Figure Q6a: Energy intensity of the Economy
Figure Q6b
Forward question
7. A recent sample survey revealed that nearly two million households in Sri
Lanka use only incandescent lamps. The 60 W lamp is most widely used. Lack of
upfront capital and cheaper electricity rates for low users have been identified as
the reasons for the continued use of conventional lamps.
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The country is facing a capacity crisis in the generating system. While diesel-fired
generators with an operating cost of 15 Rs/kWh are already operated at peak
time, there is a proposal to purchase emergency generating capacity at a cost of
25 Rs/kWh, if blackouts are to be avoided. The generating system is short of
about 100 MW of capacity to satisfy the evening peak, which lasts for about three
hours.
It has been proposed that 15 W energy efficient lamps should be distributed free
of charge to all the 3.5 million households, advising users to replace the most-
frequently used incandescent lamp in the household, with the energy efficient
lamp. Electric lighting is used in households for about three hours, and the
network energy losses are 20% of generation during the evening peak period.
Examine whether this proposal to distribute CFLs free of charge makes financial
sense from the point of view of the electricity supplier to,
(a) save on fuel costs of existing power plants
(b) possibly avoid the purchase of emergency power
(c) possibly avoid load shedding.
An energy efficient lamp costs Rs 350. You may consider a period of one year to
be the crisis period, during which the expenditure on lamps should pay back to
the Government.
Household customers pay at an average rate of Rs 12 per kWh.
For any further information required, suitable assumptions can be made.
EE5053 Tutorial 1 3
Sri Lanka Energy Balance: 2015 (In Original Units)
Renewable Electricity LPG/F. gas Petrol Naphtha Avgas Kerosene Jet A1 Diesel Fuel Oil Residual Solvents Coal Bagasse, Agro Firewood Charcoal Crude Oil
(GWh) (GWh) (kt) (kt) (kt) (kt) (kt) (kt) (kt) (FO 1500) Oil (kt) (kt) Residues (kt) (kt) (kt) (kt)
(kt ) (kt)
Supply
Primary Energy 6,429.12 196.44 12,406.07
Imports 277.00 898.98 0.14 - 270.78 1,288.85 203.26 - 1,881.46 1,676.76
Direct Exports - 22.39 - 184.56 -
Foreign Bunkers & Aviation - 0.01 -370.53 -360.62
Stock Change 6.71 -217.12 30.53 -0.13 54.96 -52.26 256.01 707.70 72.25 -0.23 85.13 94.00 - - 107.59
Total Energy Supply 6,429.12 - 283.71 681.85 8.14 - 54.96 -152.02 1,544.86 365.78 72.25 -0.23 1,966.59 290.44 12,406.07 - 1,784.35
Energy Conversion
Petroleum Refinery 9.65 154.24 136.56 75.23 154.57 516.65 541.12 11.37 1.51 - 1,692.07
Conventional Hydro Power -4,904.41 4,904.41
Thermal Power Plants 6,796.42 -144.69 -98.55 -223.09 -83.62 -1,880.01
Small hydro Power -1,064.72 1,064.72
Wind Power -343.20 343.20
Biomass Power -57.31 57.31 -94.00
Solar Power -1.87 1.87
Waste Heat
Net-metered Power Plants -38.84 38.84
Self Generation by customers
Off-grid conventional
Off-grid non-conventional -18.77 18.77
Charcoal Production 30.74
Own Use - 560.70
Conversion Losses -92.28
Losses in Transport and Distribution - 925.02
Consumption for Non Energy Use -1.28 -30.74
Total Energy Conversion -6,429.12 11,739.83 9.65 154.24 -8.14 75.23 154.57 418.10 318.04 -72.25 0.23 -1,880.01 -94.00 -1,784.35
Energy Use
Agriculture 0.31
Industries 3,880.11 57.62 8.00 109.46 683.50 86.58 196.44 4,535.74
Road Transport 1.22 836.10 1,815.11
Rail Transport 38.39 -
Domestic Aviation 2.55
Household, Commercial and Other 7,860.77 234.52 122.19 7,870.32
Total Energy Use - 11,740.88 293.36 836.10 - - 130.19 2.55 1,962.96 683.81 - - 86.58 196.44 12,406.07 - -
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Sri Lanka Energy Balance: 2015 (In thousand toe)
Sri Lanka Energy Balance 2015 (in thousand toe)
Renewables Electricity LPG/F. gas Petrol Naphtha Avgas Kerosene Jet A1 Diesel Fuel Oil Residual Solvents Coal Bagasse & Firewood Charcoal Crude Oil Total
Oil Agro
Residues
Supply
Primary Energy 1,542.99 78.58 4,714.31 6,335.87
Imports 293.62 979.88 0.15 284.31 1,353.29 199.19 1,185.32 1,727.06 6,022.83
Direct Exports -24.41 -180.87 -205.27
Foreign Bunkers & Aviation -0.01 -389.06 -353.41 -742.47
Stock Change 7.12 -236.66 33.27 -0.14 57.71 -54.87 268.82 693.54 70.81 -0.20 53.63 37.60 110.82 1,041.44
Total Energy Supply 1,542.99 300.74 743.22 8.87 57.71 -159.62 1,622.10 358.46 70.81 -0.20 1,238.95 116.18 4,714.31 1,837.88 12,452.39
Energy Conversion
Petroleum Refinery 10.23 168.12 148.85 78.99 162.30 542.48 530.30 11.15 1.35 -1,742.84 -89.07
Conventional Hydro Power -1,177.06 421.78 -755.28
Thermal Power Plants 584.49 -157.72 -103.48 -218.63 -81.95 -1,184.41 -1,161.69
Small hydro Power -255.53 91.57
Wind Power -82.37 29.51 -37.60
Biomass Power -13.76 4.93
Solar Power -0.45 0.16
Waste Heat
Net-metered Power Plants -9.32 3.34
Self Generation by customers
Off-grid conventional
Off-grid non-conventional -4.50 1.61
Charcoal Production 19.98 19.98
Own Use -48.22 -48.22
Conversion Losses -95.05 -95.05
Losses in Transport and Distribution -79.55 -79.55
Consumption for Non Energy Use -1.14 -19.98 -21.12
Total Energy Conversion -1,542.99 1,009.63 10.23 168.12 -8.87 78.99 162.30 439.01 311.67 -70.81 0.20 -1,184.41 -37.60 -1,837.88 -2,230.00
Energy Use
Agriculture 0.31 0.31
Industries 333.69 61.08 8.40 114.93 669.83 54.54 78.58 1,723.58 3,044.64
Road Transport 1.29 911.35 1,905.87 2,818.51
Rail Transport 40.31 40.31
Domestic Aviation 2.68 2.68
Household, Commercial and Other 676.03 248.59 128.30 2,990.72 4,043.64
Total Energy Use 1,009.72 310.96 911.35 136.70 2.68 2,061.11 670.14 54.54 78.58 4,714.31 9,950.08
EE5053 Tutorial 1 5
