(Reuters) – The warmth generated by human bodies in the Parisian metro will help heat a public housing project in the city center, the capital’s largest owner of social housing said on last week.

The building, located in the famous rue Beaubourg close to the Pompidou museum, is being renovated in an environmentally friendly way.

“Luckily, the building is connected to the metro through a staircase,” Francois Wachnick from Paris Habitat told Reuters.

The calories emitted by passengers, around 100 watts per person, combined with the heat from trains moving along tracks and the underground location of the metro mean that corridor temperatures are 14-20 degrees Celsius all year around.

The project, which is based on geothermal technology, aims to draw heat from subterranean passages and move it to heat exchangers before supplying heating pipes. The system will complement district heating.

The project should slash carbon dioxide emissions by a third compared to using a boiler room connected to district heating, Wachnick said.

A tender for the experimental project, which is expected to heat 17 flats, will be launched before the end of the year, and work is expected to start in 2011.

But the system, which Wachnick said is also being carried out in Austria, will not be generalized in Paris because of costs and the need to build passages to convey the heat from the metro to buildings.

“We were lucky to find a passageway that allows us to collect the heat directly from the metro, without having to pay to build one, otherwise it would have been impossible,” he added.

Article by Mathide Cru; Writing by Muriel Boselli; editing by Jane Baird; appearing courtesy Reuters and reprinted with permission from CleanTechies