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Advanced fully analytical model for U-shaped closed-loop geothermal system: Heat transport and system performance

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  • Tang, Wenying
  • Hu, Zixu
  • Yuan, Yilong
  • Hao, Dongxue
  • Chen, Rong
  • Lin, Jianqing
  • Feng, Bo
  • Xu, Tianfu

Abstract

The U-shaped closed-loop geothermal system is a key direction for geothermal development due to its high flow rate and heat extraction. Accurate performance evaluation is essential to improve utilization efficiency. Traditional analytical models inadequately describe energy transfer, while numerical simulations are complex and time-consuming, hindering rapid assessment and mechanistic analysis. This study proposes a novel fully analytical wellbore–reservoir coupling model for deep U-shaped closed-loop systems, capturing heat transfer between formation and wellbore. The model precisely analyzes the process with minimal computation, overcomes numerical-simulation limitations, and agrees well with field data. Using this model, multi-factor coupling parameter impacts are quantified: increasing drilling depth has the most significant effect on enhancing heat production efficiency, and heat loss in the shallow wellbore section is negligible, with no significant impact on overall performance. The findings provide valuable guidance for optimizing and applying U-shaped closed-loop systems under diverse geological conditions.

Suggested Citation

  • Tang, Wenying & Hu, Zixu & Yuan, Yilong & Hao, Dongxue & Chen, Rong & Lin, Jianqing & Feng, Bo & Xu, Tianfu, 2026. "Advanced fully analytical model for U-shaped closed-loop geothermal system: Heat transport and system performance," Renewable Energy, Elsevier, vol. 262(C).
    • Handle: RePEc:eee:renene:v:262:y:2026:i:c:s0960148126002065
    DOI: 10.1016/j.renene.2026.125381
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    References listed on IDEAS

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