Ground-source heat pumps (brine-to-water)
Extract heat from the ground through a closed loop (vertical boreholes or a horizontal collector). The ground stays at a stable temperature all year, so efficiency is high, although installing the loop costs more.
250 models in our database meet this; below the first 25 in order.
Criteria:
- Type (source): Ground source
- Sorted by: SCOP (35 °C) (highest first)
Only models for which these figures are known. This is a ranking by data, not a test or recommendation; the source of every value is on the product page.
| # | Model1 | SCOP (35 °C) | Rated output 35 °C | SCOP (55 °C) | Refrigerant |
|---|---|---|---|---|---|
| 1 | Thermia Calibra E Cool 8 400V BW | 7.93 | 8.86 kW | 5.41 | R452B |
| 2 | NIBE S1156-8 | 7.87 | 10 kW | 5.63 | R454B |
| 3 | Thermia Calibra 7 230V | 7.82 | 9.43 kW | 5.47 | R410A |
| 4 | CTC EcoPart 7060 | 7.81 | 61.6 kW | 5.73 | R290 |
| 5 | Thermia Mega E XL 400V | 7.78 | 75.12 kW | 5.68 | R454B |
| 6 | Thermia Mega E L 400V | 7.77 | 52.53 kW | 5.58 | R454B |
| 7 | Kronoterm ETERA M-1 HT / HK UF E | 7.72 | 12.1 kW | 5.47 | R452B |
| 8 | Bosch CS7800i LW 6 (+F) | 7.7 | 7.8 kW | 5.24 | R410A |
| 9 | Buderus WSW196i.2-6 (+W) / 186-6 | 7.7 | 7.8 kW | 5.24 | R410A |
| 10 | Kronoterm ETERA S-1 HT / HK UF E | 7.68 | 9.1 kW | 5.37 | R452B |
| 11 | Thermia Mega E M 400V | 7.63 | 60.14 kW | 5.62 | R454B |
| 12 | Thermia Calibra E 8 230V | 7.56 | 8.88 kW | 5.23 | R452B |
| 13 | Thermia Calibra E 12 230V | 7.51 | 12.24 kW | 5.52 | R452B |
| 14 | Thermia Calibra 12 230V | 7.45 | 10.42 kW | 5.36 | R410A |
| 15 | Bosch CS7800i LW 16 (+F) | 7.43 | 20.43 kW | 5.51 | R410A |
| 16 | Buderus WSW196i.2-16 (+W) / 186-16 | 7.43 | 20.43 kW | 5.51 | R410A |
| 17 | Bosch CS7800i LW 8 (+F) | 7.4 | 9.09 kW | 5.23 | R410A |
| 18 | Buderus WSW196i.2-8 (+W) / 186-8 | 7.4 | 9.09 kW | 5.23 | R410A |
| 19 | Bosch CS7800i LW 12 (+F) | 7.33 | 15.37 kW | 5.28 | R410A |
| 20 | Buderus WSW196i.2-12 (+W) / 186-12 | 7.33 | 15.37 kW | 5.28 | R410A |
| 21 | NIBE S1155-25 | 7.32 | 34 kW | 5.14 | R410A |
| 22 | Thermia Sigrin 13 230V | 7.26 | 12.8 kW | 5.6 | R454C |
| 23 | Thermia Sigrin 9 230V | 7.03 | 8.67 kW | 5.35 | R454C |
| 24 | NIBE F1153-4 | 7 | 5.2 kW | 5.45 | R407C |
| 25 | NIBE F1153-6 PC | 6.95 | 7 kW | 5.55 | R407C |
More selections
- Quietest 4–6 kW heat pumps
- Most efficient 4–6 kW heat pumps
- Quietest 6–8 kW heat pumps
- Most efficient 6–8 kW heat pumps
- Quietest 8–10 kW heat pumps
- Most efficient 8–10 kW heat pumps
- Quietest 10–14 kW heat pumps
- Most efficient 10–14 kW heat pumps
- Heat pumps with R290 (propane)
- Most efficient heat pumps for radiators (55 °C)
- Air-to-water heat pumps
- Water-to-water heat pumps (groundwater)
- Hybrid heat pumps (with a gas boiler)
Sources
- Heat Pump Keymark certificates — EHPA / DIN CERTCO (Heat Pump KEYMARK) · accessed 29 Sept 2026