EE9800007

190 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM

15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM

Olev Liik and Mart Landsberg Tallinn Technical University, Department of Electrical Power Engineering 82 Kopli Str., EE0004 Tallinn

Introduction After Estonia regained its independence, planning of energy policy became topical. Since 1989, several expert groups have worked on the urgent problems and developments of Estonia's power engineering (e.g., Eesti energeetika ..., 1990; Energy Master Plan, 1992/93). However, the researchers have not had powerful and sufficiently detailed mathematicals model capable of describing the energy sector as a whole and facilitating to study of different development strategies. Comprehensive energy system planning by mathematical modeling was accomplished in 1994. Then Tallinn Technical University acquired the MARKAL model (Fishbone & Abilock, 1981) from the Swedish National Board for Industrial and Technical Development (NUTEK). The authors of this paper took a training course at the Chalmers University of Technology, Goteborg, Sweden. First, this model facilitated data base building and conversion technology options study (mainly for electricity production) (Liik, 1995). The influence of air pollution constraints on energy system development was first investigated in 1995. At the end of 1995, under the U.S. Country Studies Program, a detailed analysis of future CO2 emissions and their reduction options began.

Model Description MARKAL (an acronym for market allocation) is a demand-driven multi-period linear programming model of a technical energy system concerned evenhandedly with supply- and demand-side options. It is a cost-minimizing energy-environment system planning model used to investigate mid- and long-term responses to different future technological options, emission limitations, and policy scenarios (Fishbone & Abilock, 1981; Fishbone et al., 1983; Kram, 1993). MARKAL was developed in the late 1970s jointly at Brookhaven National Laboratory (BNL), USA and Kernforschungsanlage-Jiilich (KFA), Germany, as part of a collaborative effort of seventeen nations under the auspices of the International Energy Agency (IEA). Today, the model is used worldwide and it is being further developed under the IEA Energy Technology Systems Analysis Programme (ETSAP). Figure 1 shows the model interfaces (Fishbone, et al., 1983). In Estonian applications, the total discounted net present cost of the energy system over the whole planning horizon has been an objective function. However, it can also be a weighted sum of this cost and the environmental emissions or security of energy supply (Kram, 1993). 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM 191

Energy Economy

Availabilities Capital of Resources requirements Technologies Economy and Limits on Useful Mining, Energy and Imports and World Demands Exports Society Trade Ecological effects Environment

Fig. 1. Interfaces of the MARKAL model.

Estonia has not yet run a hybrid MARKAL-MACRO model that combines "bottom-up" engineering model MARKAL and MACRO, a "top-down" single producer/consumer macroeconomic growth model (Manne & Wene, 1992).

Present Situation and Key Assumptions Economic Development Political and economic independence brought about drastic changes in Estonia's economy. These changes mean a transition from a highly centralized planned economy to a demand-driven and market-oriented economy, a sharp shift in the foreign trade orientation and a dramatic rise of fuel and raw material prices. As a result, in 1991-1993, Estonia's economy declined markedly. Revisions of the GDP data have been multiple, revealing discrepancies in different sources. However, these sources show that the drastic decline in economy stopped in 1993-94. Figure 2 illustrates annual growth in the GDP according to the Statistical Office of Estonia (Estonian Statistics Monthly No 1 (37) and No 10 (46), 1995). The 1995 GDP makes up 63.4% of that of 1989. Because of different accounting and monetary systems, before 1993, the evaluation of the GDP was complicated. Estonia carried out the currency reform on June 20, 1992, introducing the freely convertible Estonian Kroon (EEK) with the exchange rate at fixed 1 DEM = 8 EEK. The official exchange rate of EEK was set approximately three times lower than its purchasing power (Schipper, et al., 1994). The same source, based mainly on the World Bank reports, estimates the GDP for 1990, 1991 and 1992 at 6.6 billion, 5.9 billion and 4.4 billion, respectively (1990 US dollars). 192 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM

1990 1991 1992 1993 1994 1995

5T 3 0 •

% -5- -2,8 -6,5 -10- -8,6 -15 -13,6 -14,2

Fig. 2. Annual growth of GDP, %.

However, the Statistical Office of Estonia calculates the GDP value in EEK (Table 1). The official figure for 1993 was 21.918 billion EEK (Statistical Yearbook, 1995). However, taking into account the official exchange rate of EEK and neglecting its real purchasing power, GDP values in foreign currencies are much lower than in (Schipper, et al., 1994). During 1992-95, the total population has decreased from 1.56 to 1.5 million.

Table 1. The structure of Estonian GDP, 1993-1994

Economy sector 1993,% 1991,% Agriculture, forestry, fishing 10.0 9.2 Manufacturing 17.1 16.8 Fuels, energy and water supply 4.9 4.7 Construction 5.9 5.5 Trade 15.4 16.9 Transport, communications 11.2 9.0 Services, real estate 12.6 11.8 Education 5.1 5.0 Health and social care 2.3 3.0 Banking, insurance 2.6 2.8 Public administration 3.1 4.0 Taxes 11.3 13.5

Subsidies •1.5 •2.2

As compared to the previous year, in 1990, 1991, 1992, 1993, and 1994, average inflation was 84%, 249%, 1152%, 36%, and 47.7%, respectively (Energy Master Plan, 1992/93; Rajasalu, 1994; Statistical Yearbook, 1995). The inflation rate for 1995 was estimated to be approximately 29%. Estonia's energy sector is totally dependent on fossil fuels, its substantial part being imported. The mining and power generation equipment as well as heat production and energy networks are old and depricated, and the abatement equipment is poor or is absent. 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM 193

Estonia's domestic fuels are oil shale, peat and wood. All other fuels are imported, mainly from Russia. The share of domestic fuels in energy balance is approximately 60%. Real hydro-potential makes up less than 1 % of the present power generation capacity, whereas nuclear reactors are absent. Although the wind potential is quite substantial, in particular on islands, both technical and economical conditions for its utilization are non-existent today. Estonia's main fuel is oil shale: 99% of electricity generation and ca 25% of heat production is based on its combustion. Furthermore, it is used for shale-oil (synthetic crude oil) production (25 PJ in 1993) and as a raw material for the chemicals and the cement industry. Oil shale has an average calorific value of 8.7 MJ/kg, containing 45-50% of ash, 11-13% of moisture, 1.4-1.8% of sulphur and 0.3% of nitrogen (Energy Master Plan, 1992/93). Its carbon emission factor is 29.1 tC/TJ (Punning, et al., 1995). Oil shale is extracted from both underground mines (50%) and openpit quarries (50%). Nowadays the mines and quarries occupy ca 8% of Estonia's territory. An annual extraction was 31.3 Mt in 1980, 22.5 Mt in 1990, and 14.9 Mt in 1993. Part of oil shale is imported from Russia (16 PJ in 1993). Tables 2, 3 and 4 show primary energy resources, supply and final energy consumption (Eesti energiabilanss 1994; Energy Balance 1995).

Table 2. Estonia's primary energy resources, supply and final energy consumption

Category/Year 1990 1991 1992 1993 199+ Total resources 520.6 PJ 462.5 PJ 337.2 PJ 277.0 PJ 306.2 PJ Oil shale 54% 53% 63% 61 % 60% Fuel oil 18% 16% 11 % 14% 12% Motor fuels 11 % 11 % 8 % 11 % 12% Gas 10% 11 % 9 % 6% 7% Coal 2% 3% 3% 2% 2% Wood and peat 4% 4% 0 /o 6% 7% Electricity (hydrotimport) 1 % 2% 0 0 0 Share of domestic fuels 53% 52% 63% 62% 61 % Total supply 416.6 PJ 390.6 PJ 277.3 PJ 224.2 PJ 238.7 PJ Final consumption 213.4PJ 208.9 PJ 136.9 PJ 114.0 PJ 1K.9PJ 194 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM

Table 3. Primary energy use in 1993, %

Category Share in total resources, % Electricity generation 36.2 District heat production 19.9 Oil shale processing 9.0 Peat processing 0.8 Direct use of fuels 15.1 Non-energy use 1.1 Fuel losses 0.3 Export 3.4 Stockpiles K.2

Table 4. Structure of final energy consumption in 1993, PJ

Sector Electricity Heat Fuels TOTAL Industry 7.0 25.5 7.1 39.6 Construction 0.2 0.3 1.3 1.8 Agriculture 2.7 0.9 4.8 8.4 Transport 0.5 0.9 20.2 21.6 Households 3.9 16.5 17.2 37.6 Other economy 3.1 1.9 0.2 5.2 TOTAL 17.4 +5.9 50.8 1H.0 Losses 5.3 3.4 0.7

Key Assumptions MARKAL calculations, based on the accounting year of 1993, were planned for 45 years, divided into nine five-year periods. Table 5 illustrates the development of fuel prices during recent years (Energy Master Plan, 1992/93; Foreign Trade, 1994) and future price projections used in the MARKAL runs. Future price estimates were based on the Energy Master Plan (1992/93) and on the Swedish MARKAL data used in the Chalmers University of Technology. The 1990 and 1991 prices were converted from Soviet Roubles (SUR) to EEK (official exchange rate on June 20, 1992, 1 EEK = 10 SUR). Table 5. Import and producer prices of fuels, EEK/GJ

Fuel/Year 1990 1991 1992 1993 1998 2018 2033 Oil shale 0.117 0.169 2.22 4.41 10 15 20 Coal 0.186 0.328 9.17 13.35 20 27 30 Heavy fuel oil 0.144 0.253 17.86 18.54 30 58 65 Natural gas 0.067 0.158 13.0 29.75 35 50 55 Peat 8.7 30 Wood 0.192 0.239 7.26 8.7 30 Gasoline 0.361 1.05 43.78 50.46 70 115 130 Diesel oil 0.261 0.675 32.64 32.86 55 90 105 Approximate exchange rate 1 USD= 12 EEK 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM 195_

Two final energy demand growth scenarios were considered: increasing two-fold in fourty years and in twenty years. It was assumed that economic growth leads to significant energy conservation. An electricity consumption growth rate higher than that of heat and fuels was considered. Because new prognosis have not been publicized, the future energy demands, phase-out speed of existing capacity, and availability of new technologies are the estimates made by the authors. The early 1990s forecasts (Eesti energeetika..., 1990; Energy Master Plan, 1992/93), appear improper because since then Estonia's economy has changed drastically. Only this year, under an EU PHARE Programme project, work on Estonia's energy strategy can begin. Other key assumptions for MARKAL runs were: • long-term annual discount rate - 0.06; • no limits on fuel import and investment; • upper capacity bounds established for coal- and gas-fuelled power plants only in the scenarios with forced oil shale use; • electricity import restricted; • social and political constraints non-existent or scarcely considered in the scenarios with forced use of oil shale in power production; • no sizeable electricity exports in the future; • limit for annual wind power production is 10 PJ; • gradual elimination of so-called "commercial losses" in the electric network during fifteen years (presently ca 10% of production); • environmental constraints accounted as upper bounds on total emissions, taxes not considered.

Technological and Environmental Constraints Currently, Estonia's installed capacity of electricity generation exceeds the domestic winter peak load approximately two-fold. However, the oil shale power plants have been in operation for 23- 47 years, and their equipment appears next to the operation time limit. In the following ten or twenty years, these plants must be either reconstructed or closed (Table 6). They were designed to supply electricity to the north-west of the USSR, nearly neglecting environmental impact. During Soviet regime, approximately 50% of electricity was exported (Fig. 3). Heat is produced by cogeneration plants, boiler houses of district heating and enterprises, and small boilers of private houses. All towns, most small towns and villages have district heating networks, about 80% of apartments being connected to it (Energy Master Plan, 1992/93). Today, heat production capacity exceeds its demand about three times. 196 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM

Table 6. Electricity and heat production capacity

Plant Erected El. cap. Th. cap. Effi- Fuel MW MW ciency Eesti PP 1969-73 1610 84 29% oil shale BaltiPP 1959-66 1390 690 27% oil shale Iru PP 1981 - 190 460 49% oil, gas Kohtfa-Jarve PP 194-9-59 39 301 28% oil shale Ahtme PP 1951-56 20 102 25% oil shale Other power plants 64 138 oil, peat, diesel Boiler houses 11450 oil, gas, solids TOTAL 3313 13 225

70

60

50 /Net production 40 \ PJ / 30 / Consu np t ion ^^_^- ' +10!ses^ 20 .^ 10 / Grid losses . 0 _ 1945 1955 1965 1975 1985 1995 Year

Fig. 3. Electricity net production, consumption (incl. losses), and grid losses in 1945-1995.

The future electricity generation technology options are listed in Table 7. Such figures as investment costs, fixed and variable operation and maintenance costs, efficiencies were taken as European average values from (Kram, 1994) or from the Swedish data base.

Table 7. New generating capacity options

Planttype First year of availability Reconstruction of existing oil-shale plant 1998 New oil-shale power plant 2008 Coal fluidized bed (FB) 2008 Natural gas combined cycle 2008 Peak-load gas turbine 2003 Light water nuclear reactor 2023 Wind generator (land) 1998 Peat-fired cogeneration heat and power (CHP) 2003 CoalCHP 2003 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM 197

Air pollution data are presented in Table 7 (Energy Master Plan, 1992/93; Punning, et al., 1995; Estonian Energy, 1994). Today, CO2 is not considered as a pollutant in Estonia. According to international agreements, Estonia must reduce its SO2 emissions by 50% by 1997 and by 80% by 2005 from the 1980 level. The NOX emissions cannot exceed the 1987 level.

Table 7. Air pollution 1990-1992, thousands of tonnes. Year Solids SO, CO NO, CO, 1990 300 240 WO 74 37797 1991 278 232 390 60 33590 1992 130 177 125 30

CO2 Reduction Options The CO2 reduction options for Estonia are: • Energy conservation, more efficient appliances on the consumer side. The economically feasible energy conservation potential is estimated to be up to 50% of heat and 30% of electricity (Energy Master Plan, 1992/93). In MARKAL runs, conservation was taken into consideration by assuming low demand growth. • Change of fuels, especially reducing share of oil shale in electricity production. • New clean and efficient conversion technologies.

Result Description of CO2 Emission Scenarios

Development of CO2 Emissions by Different Scenarios Development of CO2 emissions was calculated for nine scenarios: 1. Scenarios with low final energy demand growth (doubling in 40 years): l.a. BASE - no emissions control,

1 .b. REF - reference case considering SO2 and NOX restrictions,

I.e. REF-40%CO2 - reference case + CO2 emissions not allowed to exceed 60% of 1990 level. 2. Scenarios with high energy demand growth (doubling in 20 years): 2.a. BASEH - no emissions control,

2.b. REFH - reference case considering SO2 and NOX restrictions,

2.c. REFH-20%CO2 - reference case + CO2 emissions not allowed to exceed the 80% of 1990 level. 198 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM

3. Scenarios with high energy demand growth and forced use of oil shale in power production: 3.a. OSH_B - no emissions control,

3.b. OSH_R - reference case considering SO2 and NOX restrictions,

3.c. OSH_RC - reference case + CO2 emissions not allowed to exceed 82% of the 1990 level.

Forced use of oil shale means that reconstruction of existing power generating capacity has lower bound and the corresponding upper bound is almost three times higher than in other scenarios. At the same time, upper bounds were put on the capacity of possible new coal and natural gas power plants. The results of model runs are shown in the Figs. 4, 5 and 6.

27

25 -- •••••BASE — REF -^-REF-40%CO2 23

Mt 21 --

15 1 1 —i—i—i—i—i— 1993 1998 2003 2008 2013 2018 2023 2028 2033 Year

Fig. 4. CO2 emissions under low energy demand growth.

•••••BASEH 45 - ——REFH •in - -^•REFH-2 0%CO2

35 - Mt •\ 30 - /i*^- * *

- \ 25 -

20 -

,r 1 1 1 \ 1 1 1 1 1 1988 1993 1998 2003 2008 2013 2018 2023 2028 2033 Year

Fig. 5. CO2 emissions under high energy demand growth. 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM 199

••-• OSH_B 45 - —OSH_R 40 -^•OSH_RC

35 - Mt 30

\ ••/ 25

20 -

- \^-^ 15 - 1988 1993 1998 2003 2008 2013 2018 2023 2028 2033 Year

Fig. 6. CO2 emissions under high energy demand growth and forced use of oil shale.

CO2 Reduction Costs Figure 7 illustrates increments in the total discounted system cost of all scenarios as compared to the BASE scenario (measured in 1993 GDP). The extra costs to reduce CO2 are not high because the old and inefficient oil shale power plants must be closed. Moreover, measures to reduce SO2 and NOX will also reduce CO2. Presently, approximately 50% of the 1990 level, CO2 reduction is caused by a reduced domestic energy demand and a sharp decrease of electricity exports. Expenditures for the scenarios with forced oil shale use are less than they should be. Factors related to highly extensive mining will raise oil shale price (such as opening of new mines, deeper mines, worsened quality of oil shale, environmental problems). Because no evaluations of the dependence of oil shale price on its amount extracted were publicly available, the same price forecast was used for all scenarios.

Marginal cost curves of CO2 reduction for different scenarios for 2018 are illustrated in Fig. 8. 200 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM

D ° 3 - CO

E. 2 - I 1 - wit h

o " I—I , I—I , —I— —I— '—1— X I CM LU U_ m a: o LU X O 1 I DC a. LU ti X X <^ a: LU o CO CO X CO It o O O CO CM o

Fig. 7. Increment in the total discounted system cost as compared to the BASE scenario and measured in 1993 GDP.

140 - - • - BASEH [ [ co 120 Q -•-OSH_B 100 - -x-0SH_R Q 1 LU CC CM O 80 - o j i j 60 - co O X _ . .* X BASE o 40 o a: 20 n - .,,--'-•'''7"/ ,.^^^^ 0 10 20 30 40 50 60 70 CO2 REDUCTION IN 2018 [% FROM 1990 LEVEL]

Fig. 8. Marginal cost of CO2 reduction in 2018.

Impacts of CO2 Reduction on the Development of Energy System Primary energy demand and fuel composition for the nine scenarios are presented in Figs. 9 and 10. As shown in the use of oil shale, coal and natural gas major differences exist. Nuclear energy will be used under every scenario considered here. Its share is significant in the case of high demand growth and emissions control. Wind power will be used only under the high demand growth and constrained CO2 emissions. 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM 201

Figures 11 and 12 show electricity production by fuel for all the scenarios. During 1993-2000 slow growth or even reduction in the total generation under constrained emissions is caused by a decreas in electricity exports as compared to the unconstrained cases. In 1993 electricity exports were 5.74 PJ (Energy Balance 1994, 1995). The upper limit of export was assumed to grow from this figure to 10 PJ in 2033. No electricity imports were allowed. An analysis of the new generating capacity based on (Eesti energiabilanss, 1993, 1994) and corresponding to the slow growth in demand can be found in (Liik, 1995). Results show that the construction of a new oil-shale power plant is not attractive under any scenario.

350 •MOTOR FUELS 300 nW00D 250 0 200 NUCLEAR PJ •PEAT 150 a -.— ^S^^^^BBBM^ FUELOIL 100 nGAS 50 •COAL

—»—i—i—r-—f—i—i—~ "OIL SHALE 1993 2003 2013 2023 2033 Years a) BASE

2033 1993 2033

b)REF c) REF-40%CO2

Fig. 9. Primary energy consumption under low growth in demand (including export of electricity and secondary fuels such as shale oil, coke and peat briquettes). 202 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM

1993 2033

1993 2013 2033 Years

500 . c) REFH-

1993

• Oil shale HCoal DGas • Fuel oil BPeat • Nuclear BHydro+Wind DWood • Motor fuels

Fig. 10. Primary energy consumption under high demand growth (including export of electricity and secondary fuels). 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM 203

1993 2033

180

1993 2033

180

2033 1993 2033

• Oil shale Coal DGas DON BPeat Nuclear •Hydro+Wind

Fig. 11. Electricity production by fuel under high demand growth. 204 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM

• Hydro+Wind SUNuclear • Peat PJ HOil • Gas • Coal El Oil shale

1993 2003 2013 2023 2033 Years

a) BASE

70 T-- 60 - 50- 40- PJ 30 -U- 20- 10 -

0 ,• 2DB3 1993 2003 2033

b)REF c) REF-40%CO2

Fig. 12. Electricity production by fuel under low demand growth.

Conclusions During 1990-1993, energy demand lowered due to economic decline and sharp rise in the fuel and energy prices as well as a decrease in electricity exports, has resulting in 50% reduction of CO2 emissions. For the same reasons, Estonia has been able to meet the requirements set in the agreements on SO2 and NOX emissions with no special measures or costs. To meet the rigiding SO2 restrictions and growing energy consumption in the future, Estonia must invest in abatement and in new clean and efficient oil-shale combustion technology. Along with the old oil-shale plants closing and electricity consumption growing, other fuels will be used. The increase in 15. SOME SCENARIOS OF CO2 EMISSIONS FROM THE ENERGY SYSTEM 205 energy demand then should not be fast due to constantly rising prices and efficient energy use. Measures to reduce SO2 and NOX emissions will also reduce CO2. In MARKAL runs the 1990 level of CO2 emissions will be exceeded only along with high demand growth and absence of emissions control. Restricted availability of imported fuels and nuclear power or enabling electricity import can change the results significantly. The results discussed here can also change because the data base is being improved (such as detailed description of energy networks, description of demand-side technologies, accounting of energy conservation measures, addition of new technology options).

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