Spend a day in Stockholm’s Central Station, and you’ll witness north of 250,000 passengers dashing and darting in crisscrossing directions to catch trains to and from work or home.
You’ll also be reducing the energy bill of a building across the street by 25 percent.
A Swedish real estate company, Jernhusen, is now harnessing the body heat of the rail stations's quarter million daily visitors, converting it to energy, and sending it 100 yards across the street to a 13-story building, reports the BBC.
“The people generate a bit of heat, but they do a lot of activities,” said Klas Johnasson, head of Jernhusen’s environmental division. “All this energy generates an enormous amount of heat. So why shouldn’t we use this heat? It’s there. If we don’t use it, then it will just be ventilated away to no avail.”
According to the BBC, the technology involved in the capture and conversion process isn't revolutionary:
Heat exchangers in the Central Station's ventilation system convert the excess body heat into hot water. That is then pumped to the heating system in the nearby building to keep it warm.
Using leftover body heat to raise the temperatures in a building is a tried-and-true concept.
According to Time, Minneapolis's Mall of America re-uses the heat generated from shoppers' bodies to help regulate the temperature of the complex during Minnesota's bitterly cold winters.
Jernhusen hopes to implement the system in other buildings, possibly even to heat the Central Station itself.