When deciding the criteria for the rehabilitation of Sant Pau, two premises taken into account were sustainability and energy efficiency. For this reason, geothermal energy was chosen to generate heating and cooling of the buildings.
Geothermal energy is a renewable source that uses the heat concentrated beneath the Earth’s crust. Temperature differences are harnessed by a closed underground circuit that was built with some 300 wells of different depths. Probes were placed in these boreholes to feed the geothermal heat pumps. Much of this machinery is located in underground rooms adjoining the buildings. In this way, it was also possible to preserve the heritage spaces and prevent visual pollution.
So how does this energy reach the buildings? The Art Nouveau buildings are equipped with underfloor heating and cooling. This system is based on the emission or absorption of heat by means of the water circulating inside the radiant surface. This system distributes heat or cold in a homogeneous and controlled way, and allows major energy savings.