Preliminary Study on Utilizing Closed-Loop Geothermal Systems for Seasonal Storage of Surplus Solar and Wind Energy

Abstract

The transition to renewable energy is crucial for mitigating climate change, yet the inherent intermittency of solar and wind power presents significant challenges for energy reliability. Seasonal energy storage solutions are essential to balance supply and demand, particularly in remote northern regions where extreme seasonal variations affect energy generation. This study explores the feasibility of utilizing a multilateral closed-loop geothermal system for long-term thermal energy storage, integrating surplus solar energy into the subsurface for use during high-demand winter months. A case study in Resolute Bay, Nunavut, Canada, is conducted to assess the system’s effectiveness in providing stable heat supply to a remote Arctic community. A thermodynamic model is developed to simulate heat injection and extraction dynamics, considering local geological formations, thermal conductivity, and operational parameters. Sensitivity analyses are performed to evaluate the influence of reservoir properties and wellbore configurations on system performance. Model validation is achieved through comparisons with numerical simulations. Preliminary results indicate that geothermal energy storage can smooth seasonal fluctuations in renewable energy supply, maintaining stable outlet temperatures over long-term operation. The system demonstrates potential for reducing reliance on imported fossil fuels in off-grid Arctic settlements while enhancing energy security. This study provides a foundation for future research on optimizing geothermal-based thermal energy storage solutions in cold-climate regions.