Techno-economic assessment of high-temperature aquifer thermal energy storage system, insights from a study case in Burgwedel, Germany

To mitigate the increasing greenhouse gas emissions, the technology of high-temperature aquifer thermal energy storage system (HT-ATES) is attracting the public’s attention as an alternative to traditional fossil fuels for domestic heating and cooling. Based on a wellbore model and a reservoir model, we did a comprehensive economic assessment of the target HT-ATES planning in Burgwedel near Hannover, Germany. The levelized cost of heat (LCOH), payback time, and CO₂ emission reduction are selected to assess the HT-ATES performance. Results show that the total energy loss during the stages of injection, production and reservoir storage is ca. 9%, of which ca. 2.7% during injection, ca. 2.2% during production, and ca. 4% within the reservoir. Provided that the heat exchange efficiency between the subsurface part and end-use system is 70%, the HT-ATES starts to profit from the 3^rd operation year with 30-year LCOH of nearly 2.3 cent per kWh, similar to the currently running ATESs. The 30-year net CO₂ emission reduction is ca. 58.1 kt with an average of ca. 1937 t/year, which is more considerable than the low-temperature ATES, i.e., ranging from 150 and 1500 t/year. The economic assessment of the HT-ATES indicates that the planning project can provide heating and cooling services for the district of Burgwedel with lower price and CO₂ emission.