MODELING REGIONAL DISTRICT HEATING SYSTEMS – THE CASE OF SOUTH-WESTERN SWEDEN

Other conference contribution, 2012

Biomass has become the main fuel for district heating (DH) systems in Sweden and is used both in heat-only boilers and, increasingly, in combined heat and power (CHP) plants. DH contributes also to increased sustainability through the utilization of waste heat (WH) which substitutes for primary energy use. Both the geographical distribution of WH sources and the scale effects of bio CHP plants are driving forces for the merging of DH systems. In this study, we are assessing opportunities for connecting local DH systems by transmission pipelines in the Västra Götaland region of Sweden and the system effects and costs of such investments. The assessment is carried out assisted by the optimizing MARKAL_WS model, in which the municipal DH systems in the region are represented individually as well as their relative geographical distribution. The results indicate that linking of local DH systems into larger regional systems can assist economic and environmental sustainability since it enables utilization of, currently unexploited, industrial waste heat resources. However, the cost-effectiveness of pipeline investments is dependent on the size of the available WH capacity. Furthermore, increased use of WH leads to less electricity generation from CHP in the region.