A comprehensive review of geothermal energy storage: Methods and applications

Effective or improved energy conservation is essential as energy needs rise. There has been a rise in interest in using thermal energy storage (TES) systems because they can solve energy challenges affordably and sustainably in various contexts. This study presents a comprehensive review of geothermal energy storage (GES) systems, focusing on methods like Underground Thermal Energy Storage (UTES), Aquifer Thermal Energy Storage (ATES), and Borehole Thermal Energy Storage (BTES). It highlights the significance of TES systems in addressing global energy challenges sustainably and economically. The Geothermal Energy Storage concept has been put forward as a possibility to store renewable energy on a large scale. The paper discusses the potential of UTES in largescale energy storage and its integration with geothermal power plants despite the need for specific geological formations and high initial costs. ATES is explored for its large storage capacity and lower operating costs, though it is limited to regions with suitable aquifers and carries the risk of aquifer contamination. Despite site constraints and drilling costs, BTES is noted for its minimal land footprint and adaptability to various ground conditions. The study emphasizes the role of TES technologies in transitioning to renewable energy sources, reducing climate change impacts, and providing efficient energy solutions for heating and cooling applications. The paper aims to discuss the concepts, advancements, and global statistics related to these systems. It highlights the importance of TES in addressing energy challenges affordably and sustainably, with a special emphasis on the potential of geothermal energy storage as a large-scale renewable energy solution. The paper also explores the integration of TES systems with geothermal power plants and their role in improving energy efficiency and reducing dependency on nonrenewable energy sources. Additionally, it examines the economic and technological challenges TES technologies face in the market and the need for research and development to enhance material, container, and thermal insulation designs for more complex systems like thermos-physical and chemical storage.