
Sweden's largest train station, Stockholm's Central Station, has begun harvesting the body heat of the 250,000 passengers who pass through everyday.
The station captures the excess heat from the commuters with heat exhangers in the station's ventilation system that transfer it to water-filled pipes. Those pipes send the hot water over to a building across the street, which uses it for heating. The heat harvesting has slashed electricity bills for the office block by 25 percent.
The real estate company Jernhusen, the owner of Central Station and the office block across the road, came up with the idea and created the system for the buildings when it realized that all the activity by hundreds of thousands of people was energy being lost through ventilation. Now, with the success of the system, it's hoping the idea will make its way into other buildings.
via BBC



