Scoping Study of Integrated Geothermal CO₂ Heat Pump and Water Well System in Cold Climate Region (CRADA Final Report)

Technical Report · Sun Sep 01 04:00:00 EDT 2024

DOI:https://doi.org/10.2172/3002853· OSTI ID:3002853

Sun, Jian ^[1]; Li, Yanfei ^[1]; Kashif, Nawaz ^[1]; Liu, Xiaobing ^[1]; Lian, Jamie ^[1]; Pagnotti, Anthony ^[2]; Neil, Emily ^[2]; Donald, Peter ^[2]

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1. Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
2. Dalrada Climate Technology, Escondido, CA (United States)

This study evaluates the feasibility of using ground-source heat pumps (GSHPs) integrated with water wells for residential heating demands in cold regions of the United States. Four different heat pump systems were evaluated and compared: a CO₂ air-source heat pump (ASHP), a R-410A ASHP, a CO₂ GSHP integrated with well water, and a R-410A GSHP integrated with well water. Simulations were conducted at both equipment and building integration levels, followed by a nationwide analysis across 10 selected cities. Results indicate that integrating GSHP technology with existing water wells (e.g., artesian, bedrock, drilled, and collector wells) is a feasible heating solution because of their high flow rates, good water quality, stable temperatures, and low environmental impact. Although R-410A systems demonstrate higher efficiency, CO₂ systems are more suitable for heating from contamination-free and energy security perspective. The CO₂ GSHPs maintain better performance in colder climates compared with that of ASHPs, providing higher coefficient of performance and environmental benefits because CO₂ refrigerant leakage would not contaminate well water. A national analysis confirms that CO₂ GSHPs outperform furnaces, especially in cold climates, making them a promising solution for residential heating.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Dalrada Climate Technology, Escondido, CA (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Energy Efficiency Office. Building Technologies Office
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 3002853
• Report Number(s): ORNL/TM--2024/3521; CRADA-NFE-23-09890
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY