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Title: Recovery Act: Hybrid Geothermal Heat Pump Systems Research

One innovation to ground-source heat pump (GSHP, or geothermal systems is the hybrid GSHP (HyGSHP) system. A HyGSHP system can dramatically decrease the first cost of GSHP systems by using conventional technology (such as a cooling tower or a boiler) to meet a portion of the peak heating or cooling load. We monitored and analyzed three buildings employing HyGSHP systems (two cooling-dominated, one heating-dominated) to demonstrate the performance of the hybrid approach. The buildings were monitored for a year and the measured data was used to validate models of each system. Additionally, we used the models to analyze further improvements to the hybrid approach and established that it has positive impacts, both economically and environmentally. We also documented the lessons learned by those who design and operate the three systems, including discussions of equipment sizing, pump operation, and cooling tower control. Finally, we described the measured data sets and models from this work and have made them freely available for further study of hybrid systems.
Publication Date:
OSTI Identifier:
Report Number(s):
DOE Contract Number:
Resource Type:
Technical Report
Research Org:
Energy Center of Wisconsin
Sponsoring Org:
USDOE; USDOE EE Office of Geothermal Technologies (EE-2C)
Country of Publication:
United States
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 15 GEOTHERMAL ENERGY; hybrid, geothermal, ground source, heat pump, system, control