Work

An ultra-high-temperature geothermal battery for sustainable solar power

Year: 2025

Type: article

Abstract: This study proposes a novel geothermal battery system that combines concentrated solar thermal power (CSP) with ultra-high temperature underground thermal energy storage (UHT-UTES) to address limitations in current high-temperature energy storage technologies. By utilizing CSP waste heat, this approach aims to surpass the temperature constraints of existing CSP and UTES systems, enhancing geothermal power generation and enabling a scalable, long-duration energy storage solution. A one-dimensional analytical model is developed and validated to evaluate heat transfer dynamics and thermal front propagation within the UHT-UTES system. The study focuses on three key objectives: (1) determining the optimal geothermal battery size based on available CSP waste heat, (2) quantifying efficiency gains in the bottoming cycle from surplus waste heat, and (3) assessing long-term performance through a depletion phase. Results indicate that the integrated system can sustain an additional net thermal power output exceeding n × 114 MW for 30 years (with n the number of non-interfering well doublets in the reservoir). Post decomissioning of the CSP the system allows 30 years of gradual depletion, underscoring its long-term energy storage potential and sustainability. Compared to conventional geothermal-Organic Rankine Cycle (ORC) systems, the proposed configuration delivers an average thermal energy gain of 70%. This research establishes a foundation for future studies on the technical, economic, and environmental implications of CSP integration, with a reference case based on an operational geothermal site in Indonesia.

Source: Energy Conversion and Management

DOI: 10.1016/j.enconman.2025.119892

Authors: Putra H. Agson-Gani, Klaus Regenauer-Lieb, Robert A. Taylor, Hamid Roshan, Sheikh S. Rahman

Institutions: UNSW Sydney, Curtin University

Language: English

Topic: Geothermal Energy Systems and Applications

Subfield: Renewable Energy, Sustainability and the Environment

Field: Energy

Domain: Physical Sciences

SDGs: Affordable and clean energy, Climate action, Responsible consumption and production

Open Access status: hybrid

Estimated APC paid: $4,600