Electricity dependency and CO_2 emissions from heating in the Swedish building sector—Current trends in conflict with governmental policy?

摘要

Coal-condensing power is marginal production in the deregulated Nordic power market and an increase in electricity consumption will therefore result in increased CO_2 emissions. One goal of the Swedish energy policy is to reduce the amount of electricity used for heating in the building sector. This paper investigates the potential for reduction in electricity dependency and CO_2 emissions from heating, taking the energy infrastructure into account, here defined as the capital stock of the buildings and heating systems together with geographical variations in heat intensity. In order to include the energy infrastructure in the analysis the study is made on a regional level (Southern Sweden) applying a comprehensive database describing the energy infrastructure of the region. The paper compares two scenarios for converting the heating systems of the region: one employing energy savings and with the aim to phase out the oil and most of the electricity used for heating purposes and a second which illustrates the effect if the current trend in the heating market continues. Both scenarios apply commercially available technologies only. From the second scenario it is seen that the current trend—contrary to the aim of the Swedish Governmental policy—shows an increase in electricity dependency for heating, mainly due to a large diffusion of heat pumps, but also due to installations of electrical floor heating and electricity heating systems installed in newly constructed one- and two-dwelling buildings. However, the options proposed in first scenario show that it is possible to reach significant reductions in the electricity dependency due to heating and in corresponding CO_2 emissions. An analysis of the age structure of the heating systems shows that the transformation of the heating system is not completed until the year 2025, if new investments for replacement of heating systems are made only provided they have reached their economical life time, and only applying heating technologies which at present are known to be economically competitive. It can be concluded that future policies on transforming the energy system should be based on an analysis that takes the entire energy infrastructure (in this case of heating system) into account (e.g. not directed towards single technologies). More specifically for the region studied, which is considered representative for Sweden as a whole, policies should aim at installing heat pumps to replace electricity heating only in regions with low heat density where district heating is not competitive, in contrary to the present situation where heat pumps replace all types of heating systems.