| Title | Techno-economic Performance Evaluation of Aquifer Thermal Energy Storage (ATES) |
|---|---|
| Authors | Paul FLEUCHAUS, Simon SCHÃœPPLER, Bas GODSCHALK, Guido BAKEMA, Roman ZORN, Philipp BLUM |
| Year | 2020 |
| Conference | World Geothermal Congress |
| Keywords | Aquifer Thermal Energy Storage, Seasonal Thermal Energy Storage, heating and cooling, performance analysis, shallow geothermal energy, |
| Abstract | While the share of renewables in the power generation sector steadily increases, less attention is paid to the decarbonisation of the heating and cooling sector. Since most industrial nations are located in the moderate climate zone, the global heating and cooling supply is less a matter of energy shortage than a matter of seasonal storage. Aquifer Thermal Energy Storage (ATES) is considered to bridge this seasonal gap between times of highest energy demand and times of highest energy supply. More than 80 % of all ATES systems are operating in the Netherlands and Scandinavia. This discrepancy in global ATES development is not only attributed to geological and climatic conditions, but also to several market barriers mainly of socio-economic nature. To evaluate the economic and environmental performance of ATES, the present study analysis monitoring data as well as capital costs of more than 100 low-temperature ATES systems currently in operation. With a total abstraction of 30.4 GWh heat and 31.8 GWh cold per year, the data analysis revealed only small thermal imbalances and small temperature losses during the storage period. The abstraction temperatures are around 10 and 15 °C during summer and winter, respectively. However, the temperature difference between abstraction and injection is 3 to 4 K smaller compared to the optimal design value. This indicates insufficient interaction between the energy system and the subsurface by an inadequate charging of the aquifer. Additionally, the financial analysis revealed decreasing specific capital costs from more than 1,200 €/kW for small systems to less than 300 €/kW for large buildings. A case study revealed that direct cooling with ATES systems is the most efficient supply option resulting in an electricity costs reduction of up to 80 % compared to conventional energy systems. The payback times range between 2 and 10 years. ATES is highly cost-effective for large buildings with a high cooling demand such as hospitals, airport, data canters, and hotels. |