The World Wildlife Fund (WWF) has named and shamed the operators of the 30 most climate polluting power plants in Europe. A WWF survey has ranked the "Dirty Thirty" biggest emitters of carbon dioxide per kilowatt hour produced. It finds that 27 are coal fired stations, with facilities in Greece, Germany and Spain heading the table. Germany comes off particularly badly as home to five of the ten dirtiest stations, with four of them run by large utility RWE -- the largest emitter of CO2 among European generators. "The power sector is responsible for 37% of all man-made CO2," says Imogen Zethoven from WWF. Replacing the 30 stations with renewable sources of energy would result in a massive 73.4% cut in CO2 emissions from the power sector, claims WWF. "A crucial part of the solution ... is the European Emission Trading Scheme, says Zethoven, referring to the trade of CO2 emission credits. "Only tough limits on CO2 will force the utilities to replace dirty coal plants with cleaner gas or clean renewables."