Enhancing Concentrated Solar Power (CSP) with Geothermal Energy: A Geothermal Battery Approach

Abstract This study presents an innovative approach to integrating concentrated solar power (CSP) with ultra-high-temperature underground thermal energy storage (UTES) as a geothermal battery for power generation. UHT-UTES is a combination of a CSP plant and a Geothermal Battery. The system consists of two main wells, a Brayton cycle and an Organic Rankine Cycle (ORC), which are used to convert the heat from the CSP into electricity. The ORC is used to extract heat from the CSP and the ORC is used to extract heat. The analytical solution is based on a one-dimensional (1D) approach to calculate the heat injection cycle in the battery, employing a one-dimensional approach. The numerical results show that the system can maintain more than 94% of its initial output capacity after 30 years, demonstrating the potential of this hybrid approach to enhance the longevity and reliability of renewable energy systems. The study further shows that the effectiveness of the UHT-UTES system depends on site-specific parameters, such as Direct Normal Irradiance (DNI) and subsurface temperatures.