- Basic principle of a geothermal heat pump with horizontal capture
- Prerequisites for installing a geothermal heat pump with horizontal capture
When choosing to use a geothermal heating system, you must also decide on the type of collection. For geothermal heat pumps, there are two types of capture: horizontal or vertical. Here are the specifics of horizontal capture...
Basic principle of a geothermal heat pump with horizontal capture
As its not indicated, no need to dig vertically for horizontal capture. This is the least complicated capture to implement, since it is enough to bury sensors - which will draw the heat contained in the soil - in the garden.
These sensors do not require large-scale worksince they are buried in the ground at a quite low depth, which varies between 0.6m and 1.20m maximum.
These sensors are all connected to tubes, which contain brine or a refrigerant, and run the entire surface of the required garden in coils. These pipes are of course connected to the heat pump, which is in the house; and the heat pump will be connected to a hot water tank, or a central heating system (floor heating, radiators...) to provide heating and / or hot water in the home.
Since horizontal capture does not require major work, it is the most economical solution (approximately 150 € / m², compared to 200 € / m² for vertical capture). It is therefore the one currently used most in France.
Prerequisites for installing a geothermal heat pump with horizontal capture
Although horizontal capture is the least complicated and expensive to implement, it is not always possible to opt for this solution. Because horizontal capture necessarily requires:
- A big space
To qualify for installation with horizontal sensors, you need space. The numbers are clear: the capture surface must be 1.5 to 2 times equal to the living space to be heated. 3 times, if the house is too badly insulated. If you have a house of 150m², you will need a plot of land between 225 and 300m². Otherwise, we forget.
But why such a need for space? Firstly because the horizontal sensors are connected to tubes that snake in the garden. But there must always be a space of 50cm between these tubes.
In addition, the total length of these tubes is measured in hundreds of meters: it takes space to bury them!
Finally, for a horizontal catchment system buried in the ground to work properly, it is necessary that within a radius of 2 meters to the round, there is nothing that can hinder: no well, no old tree with large underground roots, no septic tank or oil tank...
- Quality soil
It is also the nature of the land that will make possible (or not) the installation of a geothermal heat pump with horizontal capture. It is necessary that the ground be:
- Little, if not sloping. And bare: no trees, porches, terrace...
- That it is not crossed by a stream.
- On the other hand, it must be permeable to rainwater. In no case will they damage the horizontal sensors, and they promote the regeneration of the heat of the ground.
- In absolute terms, it is better to have loose soil. Horizontal catchment and rocky soil rarely mix well.
- The soil must not be too clayey: the risk with a soil of this type is that once the winter comes, ice blocks develop around the tubes. And the more we "force" on the use of the heat pump, the bigger the ice will become. To the point of completely blocking heat, and make the use of the heat pump impossible.