With the broader term of geothermal energy has prevailed to talk about when we talk about heating systems that derive energy from the ground. This energy is pumped with water/water heat pumps. These pumps operate like air pumps water only in this case exploiting the subsoil temperature, which is better than air, through a network of pipes with water. These networks can be vertically or horizontally or vertically closed circuit open circuit inside the sump with water. Geothermal pumps are characterized by very high performance coefficient 4-8 as they exploit the subsoil as a heat source or the water of the subsoil, which presents temperature stability throughout the year, with the temperature that approximates the average temperature of the atmosphere. They are financial to use and environmentally friendly.