Heat Energy Recovery From Waste Water in the Glasgow Subway System

This paper investigates the feasibility of utilizing the subsurface water ingress inside the Glasgow Subway (Metro) system. A study has been carried out in order to calculate the existing heat of the underground water. Water flow and water temperature were recorded for fifteen months within fifteen different places around the network of underground tunnels. Options were discussed and a selection of a site inside the underground tunnels for a pilot study was identified. The findings of this study developed an appropriate renewable solution and a cost effective heat pump system has been designed and implemented. At present, part of this water is being used as a source to provide heating and domestic hot water for one of the Subway's stations. The first results indicate that the energy savings compared to the old heating system and the carbon footprint reduction are substantial. An energy monitoring system monitors the energy input and energy output of the system. Further potentials after a full year of monitoring will be discussed with the customer.