Geothermal Heat Pumps
ENERGY STAR certified ground-source heat pumps, with the EER and COP spread across every loop configuration each model was rated in.
2,204 models · 49 brands
- Best
- 47.6BTU/Wh
- Median
- 24.1BTU/Wh
- Worst
- 16.1BTU/Wh
EER across 2,043 models that report it.
Geothermal (ground-source) heat pumps exchange heat with the earth rather than outdoor air. Because ground temperature is stable year-round (50–60°F in most of the US), geothermal systems maintain high efficiency even in extreme cold. EER ratings above 20 and COP above 4.0 are common — roughly 50% more efficient than the best air-source units.
Installation cost is higher than air-source systems because of the ground loop (horizontal trenches or vertical boreholes). However, operating costs are 30–60% lower, and the equipment lasts 20–25 years with minimal maintenance. Closed-loop systems are the most common; open-loop systems use groundwater directly and require permits in most jurisdictions.
Most efficient
Ranked by EER, an efficiency ratio that does not scale with size.
| Model | Brand | EER | COP |
|---|---|---|---|
| S7A(V/H)024BV1**2 | GeoSmart Energy | 47.6BTU/Wh | 5.50 |
| G7A(V/H)024BV1**2 | GeoStar | 47.6BTU/Wh | 5.50 |
| W7A(V/H)024BV1**2 | WaterFurnace | 47.6BTU/Wh | 5.50 |
| S7A(V/H)048BV1**2 | GeoSmart Energy | 41.7BTU/Wh | 5.20 |
| G7A(V/H)048BV1**2 | GeoStar | 41.7BTU/Wh | 5.20 |
| W7A(V/H)048BV1**2 | WaterFurnace | 41.7BTU/Wh | 5.20 |
| W7SZ042BV1**F | WaterFurnace | 41.4BTU/Wh | 5.20 |
| S7A(V/H)036BV1**2 | GeoSmart Energy | 40.2BTU/Wh | 5.30 |