برق تجاری و کاهش انتشار گاز CO2 در کشورهای اسکاندیناوی

Agreements on emissions of CO2 change the basic conditions for use of fossil fuels and by that the electricity markets. This paper describes, by using an equilibrium model, the challenge of meeting the Kyoto target and how the recently liberalised energy markets can help easing the joint target of the Nordic countries, Denmark, Norway, Sweden and Finland. Electricity trade serves in some cases as a substitute if emission trading is not allowed, but can even if permit trading is possible reduce marginal emission reduction costs further. The costs of meeting the Kyoto target differ among countries owing to different targets and different reduction costs. The analyses indicate that Denmark and Norway in terms of marginal reduction costs have accepted higher costs than Sweden and Finland.

In 1997 in Kyoto, the developed countries agreed to reduce emissions of greenhouse gasses of which the most important is CO2 (UNFCC, 1998). The Annex B countries have agreed upon a system of unequal percentage reductions. The target year is 2010, while the benchmark levels for the emission level are the average emissions in the period 1990–1995. Several countries (except among others USA and Russia) have on later Conference of Parties ratified the agreement and several details regarding e.g. the specific rules have been developed. The most important principles from the Kyoto agreement, namely, the emission quota trade, joint implementation and clean development mechanism are the basic principles for this development. After having agreed upon a total reduction, the EU countries agreed upon how to distribute this reduction obligation among the individual countries. Also, at this level the different percentage reductions in the countries were agreed upon. Denmark has agreed to reduce emissions by 21%, Finland has agreed to keep emissions unchanged, while Sweden and Norway have agreed not to increase emissions by more than 4 and 1%, respectively. The Nordic countries differ with respect to the composition of energy use and how electricity is generated (Table 1). These differences imply together with the different emission targets the potential gains from trade of electricity and emission permits. The Danish thermal power production is primarily based on coal, while half the Finnish thermal power production is half coal based and half bio fuel based. Norway and Sweden have already low emissions from electricity and district heating production. In Kyoto they may, therefore, have committed themselves to tight targets taking their possible abatement costs into consideration. Denmark on the other hand has a large base year emission from electricity and district heating based on coal. If this production is substituted towards less polluting fuels, emission reductions may be relatively low. Sweden has officially decided to phase out nuclear power, and one block of the Barsebäck nuclear power plant is already closed. This creates special problems in meeting the emission target as the bygone production must be substituted by other maybe more CO2-intensive production (Nordhaus, 1995, Löfstedt, 1997 and Barrett, 1998). Whether some countries are partly free riding in the Kyoto agreement is one major subject here. In Kyoto, it was also agreed that emission permits could be traded internationally, while liberalisation of the European electricity markets in the recent years implies free trade of electricity. This creates both risks and possibilities with respect to environmental policy (Eikeland, 1998 and Hauch, 1999). How trading of electricity and emission permits potentially can reduce emission reduction costs is another main subject here. One suitable model for analysing the joint problem of environmental targets and liberalised energy markets is the Elephant model (Hauch, 2000). A thorough description of the model is given in Hauch (2000). A presentation of the model and central data and assumptions are found in Appendix A. The model and the background data are crucial, which should be remembered when interpreting the results. The Elephant model is a partial equilibrium model covering the Nordic countries, Denmark, Sweden, Norway and Finland, and simulating the energy markets from the base year 1995 to 2020. In each country are modelled five energy consuming sectors and one household that demand energy for final consumption. These sectors and households demand electricity, district heating, natural gas, solid fuels, fluid fuels and an aggregate of other inputs following a top down system of nested production/utility functions. An electricity and district heating producing sector is included by a bottom up modelling. This sector chooses production level and technology use depending on relative input–output prices and technological possibilities. An overview of included technologies is included in Appendix A. Both supply level and choice of technology is determined endogenously. The available technologies are described by technological parameters determining type of fuel, efficiency, electricity–district heating ratio, emissions of pollutants and business economics. The technologies use different fuel inputs; several technologies using coal, natural gas, hydro power, nuclear fuels, bio fuels and wind power are included. Technologies installed in the base year are included in the model and through the simulation period their capacities are depreciating with a speed depending on their type. Several other models have been used in analysing similar problems, e.g. in Andersson and Hådén, 1997, Aune et al., 1998 and Amundsen et al., 1998. The models used in these works are using a bottom up description of electricity production and a top down description of other production and demand and they describe one or several of the Nordic countries. Elkraft System (2002) uses the Balmorel model to analyse a liberalisation of the Baltic electricity market and the Balmorel model is also used to analyse the Nordic power sector (see www.balmorel.com). Balmorel have a high focus on electricity production and time variation, while less attention is given to the demand system. The model used here is within this tradition but is improved in the respect that it describes all energy use and includes combined heat and power production in the technology description. It does, on the other hand, unlike in Aune et al., 1998, Andersson and Hådén, 1997 and Elkraft System, 2002, include seasonality in energy demand, which may influence the results. Even though the Elephant model, Elkraft System, 2002, Andersson and Hådén, 1997, Aune et al., 1998 and Amundsen et al., 1998 is within the same tradition, results differ among the models. These differences can in most cases be explained by differences in the models or in the scenario designs (Hauch, 2000). The most important assumption is, however, the choice of modelling tradition. Models from other traditions could generate very different results due to implicit assumptions given by the model choice. The Elephant model is designed to maximize the realism of the analyses presented here, but the results should only be used as one contribution and analyses using other models and traditions should be taken into account in policy decisions. The consequences for the Nordic electricity markets of reaching the emission targets given by the Kyoto agreement are analysed. Previous analyses covering other aspects of the Kyoto agreement include among others Lindholt, 1998, Aune et al., 1998 and Jacoby et al., 1998. In Section 2, marginal CO2-abatement cost curves for the four countries are presented. These curves are used for analysing the countries’ emission reduction possibilities and how the possibility of international trading of emission permit and electricity influence the costs. In Section 3, the Kyoto agreement is analysed. The focus of the analysis is the importance of international electricity and emission permit trading and whether some countries were free riding in Kyoto in the respect that they have committed themselves to emission targets that can be fulfilled at smaller marginal costs than in other countries. The analyses are concluded in Section 4.

Calculation of abatement cost curves for the Nordic countries, Denmark, Norway, Sweden and Finland, reveals different reduction costs. Finland and Denmark have larger reduction potentials than Norway and Sweden. If a 20% Nordic emission reduction is considered, the saving potential from emission trading is substantial compared with a situation where the countries undertake equal percentage reductions. International electricity trading can reduce emission reduction costs even when emission trading is permitted. Largest savings from electricity trading are found for emission targets of medium size. The Kyoto agreement is analysed for Norway, Denmark, Finland and Sweden. For the target year, 2010, an equilibrium price of CO2 emission permits of €60 per ton is found. The price will increase to a level above €100 per ton in 2020. This is caused by increasing economic activity that, ceteris paribus, increases the demand for fossil fuel and electricity. The emission constraints are met through a combination of reductions in use of fossil fuels in final consumption and changes in the technology choice in electricity and district heating production. Finland and Sweden export emission permits. This indicates that Finland and Sweden have managed to make a good bargain in Kyoto, if marginal reduction costs at the target level are used as an indication and the total emission target is taken as given. Electricity trade plays an important role in minimizing the costs of emission reductions under the Kyoto agreement. The Kyoto agreement changes the trade pattern dramatically even if trading of emission permits is possible.