Kristianstad and its surrounding county, with a population of 80,000, burn practically zero oil, natural gas or coal for heating, The New York Times reports. Twenty years ago, all its heat was derived from fossil fuels.
The agricultural region generates energy from ingredients such as potato peels, manure, used cooking oil, stale cookies and pig intestines. A plant outside Kristianstad uses a biological process to convert the refuse into biogas, a form of methane, which is then burned to produce heat and electricity, or is refined as a fuel for cars.
The city also burns gas seeping out of an old landfill and sewage ponds, as well as wood waste from flooring factories and pruned trees. Kristianstad officials say the city's carbon dioxide emissions have been cut by a quarter in the last decade.
The European Union's emissions trading system taxes fossil fuel consumption, and many European countries have increased their reliance on renewable energy, from wind farms to hydroelectric dams.
In Germany, about 5,000 biogas systems generate power, many of them on individual farms.