2. Geothermal heat networks

Geothermal energy extracts heat from the subsoil and uses it to heat buildings or generate electricity.

There are several types of geothermal energy for different uses:

• High-energy geothermal energy (> 150 °C): drawn from geologically active environments, it is used to generate electricity. The only French site is located in Guadeloupe;

• Low- and medium-energy geothermal energy (between 30 and 90 °C, and between 90 and 150 °C): drawn from depths ranging from a few hundred meters to 3,000 m, this deep geothermal energy is used by heating networks;

• very low-energy geothermal energy (< 30°C): present at depths of up to a few dozen meters, this superficial geothermal energy can be used to heat small installations (individual homes, buildings, etc.),...