Bochum pilot site: 5th generation heating and cooling grid in practice!
Mark 51°7 is a 70-hectare area located in the city of Bochum in Germany. It has undergone several transformations over the years: it was originally the Dannenbaum coal mine, then the Opel company produced a car factory there from 1963 to 2000.
Today, it is home to an innovative energy concept throughout the area: the fifth-generation district heating and cooling grid co-created by FUW GmbH and Stadtwerke Bochum Holding GmbH. Fraunhofer IEG is the scientific partner of the pilot site.
The unique aspect of the 5GDHC grid in Bochum is that it uses the water-filled cavities of the former coal mine, situated under the site, as the primary source of heating and cooling. Two boreholes, one 820 meters deep and the other 340 meters deep, were drilled to access the water from the mines.
Coal mines, which are usually a source of fossil fuels, can now be used as a geothermal energy source.To provide heat, the mine water, which has a temperature of around 30°C, is extracted from the boreholes and heated to about 45°C using heat pumps.
For cooling, the grid uses the shallowest borehole and pumps water from the mine, which is around 18°C.
The completion of the heat and cooling grid is scheduled for 2024.