1980年瑞典乌普萨拉市(16万人)92％的暖气依赖石油,1984年石油的需求量减少了一半,而现在仅5％的热水和蒸气是靠烧液体燃料取得的。原来,该城的能源主要靠垃圾和木头。郊区的垃圾焚烧厂由于过滤设备先进而成为世界上最干净的工厂,而且不污染空气。不过,本市的垃圾不够用,还要从半径为75公里的范围内运来。2吨垃圾相当于1吨石油。 In 1980, 92% of the heating in Uppsala, Sweden (160,000 people) depended on oil. In 1984, the demand for oil was reduced by half. Now only 5% of the hot water and steam are obtained by burning liquid fuel. It turned out that the city’s energy mainly depends on garbage and wood. The waste incineration plant in the suburbs is the cleanest factory in the world due to advanced filtration equipment, and it does not pollute the air. However, the city’s waste is not enough, but also from a radius of 75 km. 2 tons of waste is equivalent to 1 ton of oil.