Waste Water Transformed into Heat Energy

This study investigates the feasibility of utilising ground water ingress into the Glasgow Subway system. At present this unused excess water is being discharged into the city’s drainage system as waste. This valuable resource could be channelled through a Water Source Heat Pump (WSHP) to produce heat energy for domestic or public use (heating and domestic hot water). A study has been carried out in order to calculate the heat contained in the water. Water flow and water temperature have been recorded over a ten month period (since May 2014) at fifteen different points within the network of underground tunnels. Water sampling has also been undertaken at all of these points, with chemical analysis results for six of them already obtained. The measurements will continue for at least seven more months to have readings for an 18 months period. A feasibility study to review the number of support factors (i.e. Renewable Heat Incentive) that could profit the subway system has been undertaken as well. Options have been discussed and a selection of a site inside the tunnels for a pilot system has been decided and is due to be installed in June 2015. The findings of this study are expected to develop an appropriate renewable solution through a cost effective heat pump system design. This waste water will be collected and used as renewable energy. During this process energy will be produced from a waste product using a sustainable and environmental friendly method. A similar approach ought to be transferable to many other subway systems around the world, some of which experience ground water ingress.