Potential of aquifer thermal energy storage (ATES) for data centres in Germany

Abstract Data centres (DCs) produce large quantities of waste heat and thus require excessive amounts of cooling, which offers potential for an environmentally friendly space heating supply for nearby areas. However, this coupled supply suffers from a seasonal mismatch, with most space heating being required in winter, while DCs produce heat during the entire year. Aquifer thermal energy storage (ATES) systems are a cost-efficient way to overcome this mismatch and increase the utilisation of DC waste heat. In this study, we quantify the potential waste heat of 19 DCs in Germany, 13 of which are located in areas that are hydrogeologically suited for installing ATES systems. The waste heat of the DCs is quantified based on the installed cooling machines, which are detected on aerial images, their estimated cooling capacity and common DC cooling load factors. Considering typical heat recovery rates of ATES systems, the 13 DCs could supply 707 GWh th of heat. By comparing this amount of potential waste heat with local heating demands, supply areas are delineated, revealing a total of around 20,000 buildings that could be supplied. In Frankfurt, which has one of the largest accumulations of DCs in Europe, six identified DCs located in areas most suitable for ATES could supply 541 GWh th , which is equivalent to 13% of the city's residential and commercial heating demand. Considering all ten DCs in Frankfurt by placing the ATES systems in the most suitable areas, even 819 GWh th, equivalent to 20% of the area’s heating demand, could be achieved. This demonstrates the high potential of waste heat storage from DCs for urban areas with suitable subsurface for ATES systems and its importance for current and future municipal heat planning.