Underground, a stable, free and inexhaustible energyTransfer.Distribute.
Switch to closed-loop geothermal energy with WellDoneDrill and enjoy year-round thermal comfort thanks to stable, local and sustainable energy, tailored to your project in France.
Closed-loop geothermal: harness the energy beneath your feet
Closed-loop geothermal relies on vertical boreholes installed underground. They capture the heat naturally stored in the ground and transfer it to a heat pump to heat the building in winter and cool it in summer.
It is a lean, discreet and robust solution, suited to single homes as well as larger buildings, with a small ground footprint and very stable performance.
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How does closed-loop borehole geothermal energy work?
How does closed-loop borehole geothermal energy work?
The geothermal probe is a U-shaped tube (high-density polyethylene) inserted into a vertical borehole 80 to 200 m deep. A heat-transfer fluid — glycol water — circulates in a closed loop, never coming into contact with the rock or the groundwater. It captures the thermal energy of the ground, stable at around 10–14 °C all year round, and transfers it to the heat pump. The heat pump boosts this energy to produce hot water at 35–55 °C, supplying the heating (underfloor heating or low-temperature radiators) and domestic hot water. In summer the cycle reverses: the building's heat is dissipated into the ground, providing natural cooling with no significant extra consumption.
The benefits of geothermal energy
Profitable investment
A lower energy bill thanks to a free and renewable heat source.
Responsible installation
An environmentally friendly solution that reduces your carbon footprint.
Small footprint
No more oil tanks or pellet storage. Geothermal energy works without cluttering your home.
Silent system
No combustion noise or intense ventilation, for optimal acoustic comfort.
Durable equipment
Components designed to last for decades without loss of efficiency.
Minimal maintenance
A turnkey solution for heating and cooling that requires very little maintenance.
Unbeatable efficiency
With a COP far higher than that of an air-source heat pump, your system produces several times more energy than it consumes.
Heating and cooling
The heat extracted from the ground in winter is reused in summer to cool your building, with no air conditioning costs.
Frequently asked questions about closed-loop geothermal
Don't see your question here? Contact our team directly.
Contact usIt involves drilling one or more vertical boreholes to install closed-circuit probes. The system does not use groundwater directly.
They require little space, fit into many projects and provide a stable energy source that is largely unaffected by weather variations.
Yes. In many cases it allows passive or natural cooling, very useful for summer comfort.
The depth depends on the sizing, the geology and the energy needs. It must be defined project by project.
Geothermal energy for your home
Building or renovating? Geothermal energy is a sustainable solution to heat and cool your home with excellent comfort and strong long-term cost stability.
Request your quote →Geothermal energy for large projects
Developers, engineering firms, architects, installers, public bodies: we work on multi-unit residential, commercial, industrial and institutional projects.
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