Body heat harnessed for heating at Stockholm Central Station

A Swedish company has found a way to harness the body heat of people passing through Stockholm’s Central Station and use it to warm an office block across the road. Jernhusen, a real estate firm based in Sweden’s capital, developed a system to harness the usually wasted natural resource that is produced by everyone.

“This is old technology being used in a new way,” said Klas Johnasson, one of the creators of the system and head of Jernhusen’s environmental division. “The only difference here is that we’ve shifted energy between two different buildings.”

“There are about 250,000 people a day who pass through Stockholm Central Station. They in themselves generate a bit of heat. But they also do a lot of activities. They buy food, they buy drinks, they buy newspapers and they buy books,” added Johnasson in a BBC report.

“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.”

The system works by exchanging excess body heat caught in the station’s ventilation system into hot water which is then pumped into the heating system of the opposite building. The arrangement has saved the office block 25 percent in energy costs and also reduced its carbon footprint significantly.

“This is generally good business,” said Mr Johansson. “We save money in energy costs and so the building becomes worth more. We are quite surprised that people haven’t done this before. For a large scale project like Kungbrohuset (the office block) this means a lot of money.”