District Heating and CHP – a Vital Role for the Development Towards a Sustainable Society?

In Sweden, district heating (DH) is quite well developed and is already mainly based on non-fossil fuels. Increased use of DH is therefore considered as a way of phasing out fossil energy for heating purposes. Furthermore, increased use of DH provides an increased basis for combined heat and power production (CHP). Considering that coal condensing is the marginal production of electricity in Europe, increased use of biofueled CHP leads to even greater reductions of global carbon dioxide (CO2) emissions. However, in a sustainable society, where there is no longer a systematic increase of CO2 (and no other sustainability problems), the benefits of DH are less obvious. The aim of this work is to explore the impact of DH and CHP in the development towards such a society. A local energy system is studied for five different time periods from 2010 to 2060 with different marginal technologies for electricity production. Results show that when the local energy utility co-operate with a local industry plant and invests in a new CHP plant for waste incineration the global CO2 emissions for the whole studied time period will be reduced with about 48 000 tonnes, which corresponds to over 100 % of the emissions from today’s system for the same time period. When considering that bio fuel is a scarce resource, and that the amount of CO2 emission linked to waste probably will be lower in sustainable society, the global CO2 emissions will be about 250% lower compared to the system of today. The studied DH related cooperation and introduction of CHP will reduce the system cost for the whole studied energy system with 2 500 MSEK for the studied period. In general, the results indicate that the modeled measures will not have any major advantages over other heating technologies in a sustainable society but that it can play a vital role for the development towards such a society.