Impact of distribution and transmission investment costs of district heating systems on district heating potential

Abstract

In this paper, we use a heat density map (HDM) and a plot ratio map to propose a GIS-based method for determining potential DH areas with specific focus on district heating (DH) grid costs. The DH areas are determined via performing sensitivity analyses on the HDM under consideration of predefined upper bound of the average distribution costs. The approach additionally allows for estimation of length and diameter of transmission lines and their associated costs. The outputs are GIS layers that illustrate areas that are economically viable for construction of DH as well as the cost-minimal transmission lines connecting these regions to each other. The impacts of key input parameters like grid costs ceiling and market share on potential and on expansion and extension of the DH systems were studied for the case study of Vienna. The results showed that the increase of DH market share in DH areas under a certain grid cost ceiling significantly reduce average grid costs. In addition, it was revealed that the expansion of DH system without increasing the market share in the DH areas does not effectively increase the share of DH from the total heat demand and leads to higher average grid costs. These results call for policy interventions like spatial heat planning, zoning and implementation of district heating priority areas.