Methodology to evaluate and map the potential of waste heat from sewage water by using internationally available open data

Abstract

The integration of waste heat from industrial processes has been identified as a major research area in the European Union strategy on heating and cooling. In fact, the waste heat potential of combined cycle gas turbine power stations or energy-from-waste plants is well known. Plenty of district heating networks, in markets of different maturity across the world, make use of this technology. This work contributes to the wider integration of low-grade waste heat from sewage water systems by providing an open data methodology that can be easily adapted to various types of cities and district heating systems under changing boundary conditions. The methodology provides an easy calculation of waste heat potential for a city using population density and geographic information system data. The methodology identifies suitable sites for the integration of heat sources into district heating systems or building heating. It is based upon open-source technology and open data that helps to map waste heat sources spatially. Graph theory is key to generating a generic sewage network needed to carry out the methodology. The methodology will be applied and validated at an example city in Germany.