Using body heat as energy
Commuters who pass through Stockholm’s Central Station may not know that they are heating a building across the street.
This BBC video shows that Jernhusen, a real estate company in Stockholm, has found a way to channel body heat from people to heat another building. This is done by using heating exchangers to convert the Station’s trapped body heat into hot water and then pump that water to an office building next door, providing an environmentally-friendly and cost effective heating.
The engineers say that this process can reduce a building’s energy costs by up to 25 percent.

