Economic evaluation and optimization of development models for geothermal resources of Well HR-1 in Huizhou, Guangdong

Economic evaluation and the selection of development models suited to local needs are crucial for the sustainable development of geothermal resources. Southern China, characterized by a developed economy and a hot-humid climate, exhibits a strong demand for new energy, particularly low-carbon cooling solutions. The geothermal resources in this region are mainly deep-circulation, medium-low-temperature (&lt; 150 ℃) hydrothermal systems, suitable for power generation, cooling, and direct utilization. Taking Well HR-1 in the Huangshadong geothermal field of Huizhou, Guangdong Province (wellhead temperature 110 ℃, flow rate 130 m ³/h) as a case study, this research conducts a 20-year life-cycle economic evaluation employing four methods: static payback period (SPP), dynamic payback period (DPP), net present value (NPV), and levelized cost of energy (LCOE). The economic performance of six distinct development models is comparatively analyzed. Two of these models are single-purpose systems: organic Rankine cycle (ORC) and absorption refrigeration system (ARS), with domestic water system (DWS) serving as the tail water treatment component. The remaining four models are cascaded utilization systems: ORC-ARS, ORC-DWS, ARS-DWS, and ORC-ARS-DWS. The results demonstrate that for Well HR-1 as medium-low temperature geothermal resources, the two-stage ARS-DWS cascaded utilization model performs best across key economic indicators, with a DPP of 1.42 years, NPV exceeding 139 million CNY, as well as an LCOE of 0.041 CNY/(kW·h). Sensitivity analysis further confirms the economic stability of this model under varying operational parameters and electricity price fluctuations. Based on this case study, the research suggests that the medium-low temperature geothermal resources in Southern China should prioritize the ARS-DWS cascade utilization model. This study provides a quantitative decision-making basis for the development and utilization of similar geothermal resources in the region. <sec><label/><title/><fig id="F1"><alternatives><graphic specific-use="print" href="./online/1000-2618-2025-42-6-631-F001.jpg" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="./online/1000-2618-2025-42-6-631-F001.jpg"/><graphic specific-use="online" href="./online/1000-2618-2025-42-6-631-F001c.jpg" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="./online/1000-2618-2025-42-6-631-F001c.jpg"/></alternatives></fig></sec>