Geothermal draws heat from the ground, whose temperature stays a stable 10–12 °C all year round in Belgium. The result: a seasonal efficiency (SCOP) of 4.5 to 5.5, independent of the weather. The investment is heavier, but it delivers the lowest heating bill over time.
The figures that matter for the highest-performing heat pump on the market.
Thanks to the stable temperature of the ground, geothermal reaches the highest efficiency of any heat pump, even in severe outdoor cold.
Loops buried at shallow depth over a large garden area (1.5 to 2 times the heated surface). Cheaper than drilling, but it requires land.
One or more vertical probes drilled into the ground. Little ground surface used, maximum efficiency. More costly but ideal when land is limited.
In summer, the reversed circuit circulates the cool water of the ground through the underfloor heating: passive, almost free cooling.
Like air-to-water, geothermal supplies domestic hot water via a tank, with even better efficiency.
The heat pump itself lasts 20–25 years. The collector (loops or probes) lasts several decades with no maintenance. The investment is built to last.
* Indicative values. Efficiency and the type of collector depend on the soil and the land — a geological study is carried out before the quote.
Geothermal is the highest-performing heat pump, but also the most demanding to install.
It stands out when the land and budget allow, and when performance is the priority.
The ideal moment: the collector fits into the groundworks. Paired with underfloor heating, geothermal delivers its best.
If the garden offers the surface for horizontal loops, geothermal pays off over time despite the higher initial cost.
Vertical drilling needs little ground surface. The cost of drilling is higher, but performance is at its maximum.
The air-to-water heat pump offers an excellent performance/price compromise without a collector. And the hybrid heat pump allows a gradual transition.
A 200 m² villa with an end-of-life oil boiler. Two 100 m vertical probes drilled in the garden, geothermal heat pump paired with the existing underfloor heating. SCOP measured at 5.2, heating bill divided by four. Geocooling cools the ground floor in summer without a compressor.
5.0/5 · 3verified reviews
« Châssis, panneaux et pompe à chaleur en une seule fois : on a eu un seul devis, un seul planning et zéro paperasse pour les primes. Le résultat est impeccable et notre facture d'énergie a chuté. On ne pensait pas que ce serait aussi simple. »
« Passage du mazout à une pompe à chaleur air-eau. Chantier propre, anciens radiateurs conservés. La maison est mieux chauffée pour bien moins cher. »
« PAC air-air réversible installée avant l'été. Confort été comme hiver, et le SAV répond vite. Très satisfait du suivi. »
Geothermal leads on efficiency. See how it compares to the alternatives.
| Critère | GeothermalVous êtes ici | Air-to-water heat pumpVoir la gamme → | Hybrid heat pumpVoir la gamme → |
|---|---|---|---|
| Efficiency (SCOP) | 4.5–5.5 | 3.5–4.8 | 3.5–4.5 |
| Stability in severe cold | No loss | Efficiency drops | Boiler takes over |
| Investment | €€€€ — the highest | €€€ — mid-range | €€€ — mid-range |
| Cooling | Passive geocooling | Depends on model | Depends on model |
| Land needed | Yes (horizontal) or borehole | No | No |
| Grants 2026 | Very well supported | Well supported | Supported |
| Best for | New build, long term, performance | Boiler replacement | Gradual transition |
Cheaper and without a collector. The go-to choice for replacing a boiler.
Compare with air-to-water →The simplest and most affordable. Heat and cold, without a water circuit.
Compare with air-to-air →The smooth transition: heat pump + boiler as backup for severe cold.
See hybrid →The ideal emitter for geothermal: low temperature, maximum SCOP, geocooling.
See underfloor heating →Installed geothermal price ranges and 2026 regional grants.
See the prices →An overview of our heat pump solutions in Belgium.
Back to the heat pump guide →The cost is higher than air-to-water, mainly because of the collector. Here are some benchmarks for installed equipment.
See heat pump prices & grants in detail →* Indicative ranges, collector included. The cost of drilling depends on the local geology.
For the horizontal collector, yes: you need 1.5 to 2 times the heated surface. For the vertical borehole, no: a 100 m probe takes up just 20 cm of ground. The choice depends on your land.
The drilling works last 1 to 2 days and require access for a rig. Reinstating the ground is included. After a few weeks, there is no visible trace.
Perfectly. The Belgian ground stays at 10–12 °C all year round from 1.5 m deep. That is enough for excellent efficiency, in both winter and summer.
Generally yes. Vertical drilling requires a declaration or a permit depending on the region and the depth. We handle the formalities for you after the geological study.
Yes, and it is ideal: the panels supply the electricity the heat pump consumes. Combined, they cut the energy bill to almost zero.
Yes. The higher initial cost is offset by the lowest heating bill of any heat pump. And the collector lasts 50+ years — you can replace the heat pump without redoing the probes.
Free technical survey, soil study, grants calculated. Describe your project in under a minute.