# Deep Geothermal Energy

Deep geothermal energy at high temperature is defined in the French mining code by a temperature higher than 150°C and a depth greater than 1500m.

The main impediments to deep geothermal reservoir development are the technical challenges involved in producing heat and electricity with this natural source of energy.

The word “Geothermal” originates from ancient Greek Geo (Earth) and Thermal (Heat). The natural heat of the Earth comes from two main sources: the heat of the Earth’s core (5000°C at 6000km deep) and naturally occurring radioactivity.

From the surface to 5000m deep and from 15°C to 200°C, geothermal energy can be exploited through many techniques.