Friends of the Earth is urging consumers to start pulling the plug on the country's polluting nuclear and fossil-fuel power companies. The environment group's call comes as all power companies are for the first time obliged to tell their consumers how polluting their electricity is.

From this week, new European-wide rules mean that electricity supply companies have to say how much pollution is generated by coal, gas, nuclear and renewables, and how much carbon dioxide and nuclear waste results from their activities. The figures reveal that Powergen and ScottishPower generate the most carbon dioxide emissions for each unit of electricity supplied while British Gas and EDF Energy generate the most nuclear waste per unit.

The data also highlights a number of companies who rely instead on non-polluting renewables such as wind power. Friends of the Earth's Climate Campaigner Martyn Williams said: "Consumers wanting clean energy should stop propping up polluting power companies, vote with their purses and switch suppliers.

But the Government must do more to ensure more of our electricity comes from cleaner sources. "Even electricity companies have told Ministers they want a clear policy framework for cutting greenhouse gas emissions to ensure investment in clean energy sources. The Government must stop dithering, recognise that the UK public does not want nuclear power and commit more to developing renewable energy."

Friends of the Earth is calling on the Government to set legally binding targets to cut carbon dioxide emissions by three per cent each year. Eight major energy companies wrote, along with Friends of the Earth, to key Ministers saying that: "a clear pathway to the 2050 emissions reduction target would enable a sustained shift across the economy that would enable market to react accordingly. We recommend that consideration should be given to the proposals for a statutory framework to ensure that the UK reduces its greenhouse gas emissions". The figures also suggest that some companies are attempting to downplay the amounts of nuclear power they really use. Despite the fact that 21% of Britain's electricity is generated by nuclear, none of the companies admit to using anywhere near these amounts.