1. Technique
This technique is the most suitable for an area with limited
space. It is enough to dispose the minimum surface to achieve
the operations of vertical drilling.
The capturing of the calories with vertical detectors requires
drillings spaced min. 5-10 m, realized close to the house or
under it before its construction. Geothermal sensors made of
polyethylene tubings in U-shaped are introduced in the wells.
After the installation of the sensors the holes are sealed with a
mixture of gravel or fine vibrated sand and 'Bentonite', chose to
assure a good heat conduction and a good protection against
possible landslides, root attacks, …
Then the principle is the one of a WATER/WATER heat pump with
glycol water which circulates in a closed circuit in the senors to
fetch the calories present in the natural cellar. The
WATER/WATER heat-pump is a standard equipment, which
generates the best performance coefficient, the house-side
network is a classic installation of the type of floor heating or of
central low-temperature heating; which gives a quite simple
installation beside the drillings which demands a precise effort
and study.
The yields or performance coefficients are excellent (4 and
more) because, from a depth of 12 m, the ground has a relatively
constant temperature of 10°C, in any season, which corresponds
to the optimal conditions to use the ground as a resource of
heat.