Sweden might be cold, but humans are always warm, no matter where we live. The Swedes decided to take advantage of this fact to heat buildings around Stockholm’s Central Station.
About 250,000 people pass through the train station each day, eating, shopping, running to catch their train - which means a lot of body heat is generated. Jernhusen, a real estate company that runs the railway station as well as several surrounding buildings, developed a way to channel body heat to warm a building across the street.
According to a BBC article, the station is fitted with heat exchangers that convert excess body heat into hot water which is then pumped to a different building to keep it warm. Don’t be creeped out, though, Swedish commuters. The system isn’t stealing your body heat or anything; it’s just using surplus heat that would otherwise be lost to the atmosphere.
Jernhusen claims that the system is not only environmentally friendly, but also lowers energy costs by 25 percent.