I know I should be furious. The EDF takeover of British Energy means that four nuclear power stations could now be built around the UK, the first nuclear new build in a generation. As a long-standing Green party member, one who chops his own wood, grows his own leeks, keeps chickens and puts the kids in washable nappies, antinuclear indignation should spring easily to my lips.

After all, energy is something I care about. The last time I checked my carbon budget, I came in at a fifth of the national average. I rarely fly, even when booked to address faraway audiences about my personal obsession, climate change – a subject I’ve covered in three books. Whenever the word “nuclear” comes up at my talks, a shudder runs through the room. Because everyone knows that real environmentalists loathe nuclear power. It is just evil. Full stop.

Except, well, I don’t believe that any more. Just a month ago I had a Damascene conversion: the Green case against nuclear power is based largely on myth and dogma. My tipping point came when I discovered just how much nuclear power has changed since I first set my mind against it. Prescription for the Planet, a new book by the American writer Tom Blees, opened my eyes to fourth-generation “fast-breeder” reactors, which use fuel much more efficiently than the old-style reactors, produce shorter-lived waste and can also be designed to be “walk-away safe”.

Best of all, these new reactors – prototypes of which have already been tested – can produce power by burning up existing stocks of nuclear waste. As Blees puts it: “Thus we have a prodigious supply of free fuel that is actually even better than free, for it is material that we are quite desperate to get rid of.” Who could object to that?

Just about everyone on the eco-scene, it turned out. I began to receive e-mails from friends and colleagues warning me off the topic. Did I really want to risk my entire reputation by alienating the green movement? The backlash to my first magazine article on the subject prompted my inbox to collapse, the blogs to drip with venom, the dirty looks to multiply.

A former Greenpeace campaigner posted on my website that I needed to show “a bit of humility” and “less arrogance”. On Greenpeace’s blog my views were mocked as “wishful thinking of the day”. On Radio 4’s Today programme, Green party leader Caroline Lucas accused me of having “lost the plot”. When I argued back, she accused me of “just being silly”. I was a traitor.

This was a moment I had been dreading for nearly three years, ever since I first suspected that much of what I had been brought up to believe about nuclear power – that it is, without exception, dirty, dangerous and unnecessary – was untrue. Science has moved on. The old figures just don’t stack up any more.

According to the Intergovernmental Panel on Climate Change, nuclear is just as low-carbon a power source as wind and solar: the world’s 439 operating nuclear reactors save the planet from 2 billion extra tonnes of carbon dioxide per year, which would have been emitted had coal been used instead.

And those dangers? They’re still there but we need to discuss them truthfully. Take Chernobyl. We all know it was a disaster: the Greenpeace website states a death toll of 60,000 already and predicts another 140,000 deaths in the future. But these statistics fly in the face of mainstream science: according to the World Health Organisation and the United Nations Scientific Committee on the Effects of Atomic Radiation, 28 people died in the initial phase and several thousand more have suffered from nonfatal thyroid cancer because of the accident. The UN report concludes that “there is no evidence of a major public health impact attributable to radiation exposure 20 years after the accident” – so the real death toll from the world’s worst nuclear accident is tiny. On a deaths per gigawatt-year basis, nuclear is safer than coal and oil.

Curiosity whetted, I searched the scientific literature for evidence to support the other great green charge levelled at nuclear power: it kills its neighbours. I sifted through piles of rigorous epidemiological studies from all over the world, searching for proof that people who live near nuclear sites are more prone to cancer and leukaemia. None of the reputable journals turned up a link.

These are just two examples of eco-myths: there are many more. If only we were allowed to discuss them without being flayed for heresy.

When I e-mailed a senior ecological scientist with my conclusions, he agreed, but only privately. “Do not cite me as promoting nuclear,” he begged. I am still shocked that people of his stature are too intimidated to speak out. The result of this fear is that the public is dangerously misinformed about nuclear power.

I have finally thought of something useful that I can do with my Green party membership card: I’ll auction it on eBay and send the money to EDF – with a suggestion that it beefs up its marketing department. Any bids?

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