- What is geothermal or hydrothermal?
- The study of thermal needs before installing a geothermal heat pump
- The study of the basement before installing a geothermal heat pump
Enjoy the warmth of the basement to heat your home is now possible thanks to geothermal energy. But to dispose of this natural resource, inexhaustible and free, it must be able to collect and distribute throughout the house. This is the role of the geothermal heat pump. Be careful, however, because setting up such a system can not be improvised. It requires a set of geothermal studies prior to installation.
What is geothermal or hydrothermal?
Geothermal energy consists of using the heat naturally present in the basement (geothermal) or in a water table (hydrothermal) to heat a house. The deeper we go in the basement, the more the temperature increases. But at a given depth it remains almost constant whatever the time of the year. In the same way the water of a water table varies between 7 and 12°. It is therefore a resource always available and inexhaustible.
In this case, it is called geothermal very low temperature because the recovered temperature does not exceed 30° and the drilling is less than 100 m deep.
This heat is recovered via sensors, comprising a heat transfer fluid, sunk in the subsoil or in the water table. It arrives in a geothermal heat pump which thanks to a compressor, raises this temperature then distributes it in the house or ensures the hot water.
A reversible heat pump can also cool a home by transferring the ambient heat to the basement.
The study of thermal needs before installing a geothermal heat pump
Before installing a geothermal heat pump, you must have determined your needs. Would you like to heat all or part of your home? Throughout the year, or will an additional heater take over if needed? Do you want to ensure the production of hot water? Do you want to enjoy air conditioning?
If you build, RT 2012 (Thermal Regulation 2012) requires you to ask all these questions and consider the different alternatives.
In renovation, you will have to part of the existing: Surface, orientation, insulation, glazed area, air renewal, occupation period, etc. This study may show you that insulation work is needed or that you can better manage your heating depending on your absence or presence.
Do not neglect this part of the geothermal study which has the advantage of posing concretely and globally the question of your heating.
The study of the basement before installing a geothermal heat pump
The goal of geothermal energy is to go for heat in the basement or groundwater, the nature of it is very important. The geological study of your soil is an essential element before installation.
Technically all floors allow to install a geothermal system. On the other hand some soils are more easily exploitable than others: a sandy soil gives half less yield than clay soil. A rocky soil also provides less heat and is difficult to drill.
The nature of your land and its size, will also guide the choice of calorie sensors:
- Horizontal sensors if you have room and if your soil is favorable for energy transfer. But beware, they are sensitive to prolonged frost.
- Vertical sensors, that is to say, pressed into the ground. They are particularly well suited if you lack space and their performance is better. But they are more expensive.
They are the only ones adapted to hydrothermal since it is necessary to go to get the water table in depth. It is then necessary to determine the characteristics of this one (Depth, volume, variations, etc.)
- Elliptical sensors which appear as big coils installed in the ground. It is a mix between the two types of previous sensors.
It is according to your needs and the possibilities offered by your basement that you can make an informed choice of a geothermal heat pump adapted. That's why it's important that you pay close attention to pre-installation geothermal studies.