Thermal performance and analysis of high-temperature aquifer thermal energy storage based on a practical project

Geothermal heating technology based on high-temperature aquifer thermal energy storage (HT-ATES) is one of important development directions of geothermal multi-energy complementary and integrated energy system. In present article, thermal performance of HT-ATES based on a practical project is first proposed, and a long-term cycle of HT-ATES is constructed and verified. The heating up storage and isothermal heat storage of HT-ATES are experimentally conducted. The different standing time schemes causing mutation of the heat storage mechanism have been implemented to identify the optimal scheme. And then the outlet water temperature, heat storage efficiency is further calculated and analyzed under the same and different conditions of heat storage capacity. Compared with original heat production, the outlet water temperature is promoted and the single well heat storage efficiency can reach >80 % after 9 years of heat storage. The heat storage flow rate decreases or the heat storage temperature increases can prevent heat dissipation to the surroundings, so that obtaining high outlet water temperature and heat storage efficiency under the persistent annual heat storage capacity. Results also show that the outlet water temperature and heat storage efficiency are promoted when the heat storage temperature increases and heat storage flow rate decreases.