Scientists are always trying to find new green energy. Now, some scientists in Sweden have found one: the heat from our own bodies. They are putting together the heat that our bodies give off naturally, and using it to heat buildings.
In general, the temperature of the human body is about 36.8C and we are always giving off some heat because our bodies are usually much warmer than our environments around us. When many people get together, they can produce a lot of heat.
About 250,000 people pass through Stockholm Central Station each day.' Their bodies produce a lot of warm air. Usually, ventilator fans(换气扇) would guide this warm air to the outside of the station and it would be lost. But the Swedish scientists are using a piece of equipment to catch the warm air and guide it to heat underground water tanks (水箱). The warmed water from these tanks makes heat enter an office building about 60 metres away. As a result, the building's energy costs are down by 20%.
There are problems, of course. “It's very hard to move low-temperature heat very far," says Lester Lane of Carnegie Melon University. "You must be careful," he says," not to use more energy than you save when passing on the warmed water to another place.
The Swedish scientists say that, however, this is not a big problem and, after. all， they want to use body heat more to heat homes and other buildings. This would make energy cheaper and the environment better.
①The heat makes underground water tanks become warmer.
②The heat is passed on to enter an office building.
③Use a piece of equipment to collect our body heat.
