It must be quite hard generating good green PR for the power company E.ON, which is trying to get permission to build Britain's first coal-fired power station in more than 20 years. So well done the press office last week for its offering that "the future's bright at E.ON's Ratcliffe-on-Soar power station".

The station has become "a little greener" by putting 68 solar panels on the roof "to help heat and light the admin block". Its team leader on the environment, Christine Smith, says: "It's a great way to show how new, renewable technology can be integrated with the more traditional way of generating electricity."

"Integrated" is not quite the world I would choose. The company boasts that it will save an estimated 6.3 tonnes of carbon dioxide emissions a year. Green Party candidate and author of the Carbon Commentary blog Chris Goodall emailed me to point out that that is about one millionth of the emissions from the power plant itself. So, taking account of the saving, the plant's net emissions are now 99.9999% of what they used to be.

Actually, Chris, I think you were too generous. According to Carma (Carbon Monitoring for Action), which keeps tabs on major CO2 emitters round the world, the 40-year-old plant emits 12.8 million tonnes of CO2 a year. It is Britain's third largest source of CO2 into the air. So make that about half of one millionth. Eon is the company that wants to build a new coal-fired power station at Kingsnorth in Kent.

To be fair, the company recognises that a few solar panels on the roof may not be enough to secure government permission. Especially now the energy and climate change secretary, Ed Miliband, has promised a thorough look at the environmental implications of its plans.

Eon's trump card has been to promise that Kingsnorth will be "carbon-capture ready". That is, it will be designed so it is able to bolt on equipment to capture CO2 from the stack emissions and send them off for burial under the sea, or wherever, just as soon as the technology is ready for commercial application.

As we have reported here before that day is about $20 billion and probably a couple of decades away. By then, of course Kingsnorth may have emitted, by my estimate, some 120 million tonnes of CO2. But at least Kingsnorth will be ready.

Except that we are only now learning the extent to which the coal industry is unprepared to pay the billions to get carbon capture to the state when it can be used in anger against climate change.

Last month we learned that the "clean coal" guys are playing dirty. Paul Golby, chief executive of E.ON UK talked at length about the investment needed to make it happen, before dumping the whole deal into the government's lap. "If they fund it, we will fit it," he said.

Excuse me, Mr Golby. You ask the government to break all its promises about a clean energy future in order to allow you to build a coal power station, because you have this great new technology just round the corner that will make it miraculously green after all. Then you add innocently that, of course, the government will have to pay to develop that technology.

To add to the insult, the "pay up or else" threat was made at the London-based Adam Smith Institute, which describes itself as Europe's top "free market think tank". Call me naive, but I thought free marketers paid their own bills rather than relying on government largesse.

I guess we should be pleased that Golby has laid it on the line about who they expect to foot the bills. It's us. Meanwhile, I hope the sun shines on their solar panels.

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