Former Environment Secretary Owen Paterson will this week deliver a stark warning – that Britain will 'run out of electricity' unless it abandons its main green energy target.

Mr Paterson, who was sacked from the Cabinet in this summer's reshuffle, will argue in a lecture that the target enshrined in the Climate Change Act – which binds the UK to reducing emissions by 80 per cent by 2050 – is unaffordable.

He will go on to say that the current energy policy is a 'slave to flawed climate action', and warn that 'in the short and medium term costs to consumers will rise dramatically'.

In Wednesday's lecture, organised by the 'sceptic' think-tank Global Warming Policy Foundation, which is chaired by former Tory chancellor Lord Lawson, he will say: 'There can only be one ultimate consequence: the lights will go out.'

Because the Act forces Britain to invest in renewable electricity sources, mainly wind, he claims it 'blocks other feasible policies that would cut both emissions and costs'.

Previous energy secretaries –Labour's Ed Miliband and the Liberal Democrats' Chris Huhne – claimed to want to help the poor, he will say.

But Mr Paterson believes their actions led to 'the most regressive policy since the Sheriff of Nottingham' – with vast subsidies on consumers' bills going straight to the pockets of landowners and green investors.

He will go on to stress that although he has been accused of being a 'climate denier', he accepts the main points of greenhouse theory.

But he will point out that temperatures have risen much more slowly than scientists predicted, while by some measures, the current 'pause' in global warming has already lasted for 18 years.

To stand a chance of meeting its obligations, Britain should be building a new giant nuclear power station every three years, as well as thousands more of the turbines which have 'devastated landscapes, blighted views, killed eagles and carpeted the very wilderness that [greens] claim to love'.

Instead, Mr Paterson will argue, policy should focus on supplying cheap energy and cutting emissions. This, he says, can best be done by fracking for shale gas and building small gas and nuclear-powered electricity stations.

Mr Paterson told The Mail on Sunday that adding green energy costs to people's household bills and building onshore wind farms are policies that are sending Tory voters into the arms of Ukip – the only party committed to scrapping them.

'Ukip's opposition to green energy targets and wind is tapping a tremendous tide of anger felt across the country,' Mr Paterson said, adding: 'Everywhere I go, this issue comes up all the time. You could live with that if the policy was actually working, but it's not. If we change direction on this it will make a huge difference.

'It's an opportunity for the Tories to steal one of Ukip's most popular campaigns.'

Changing course would require the Climate Change Act's suspension, and possibly its eventual repeal, while the separate targets imposed by the EU would have to be part of the treaty renegotiation Mr Cameron has promised if the Tories win next year's election.

Mr Paterson insisted he was not trying to embarrass the Tory leadership, saying: 'I want to be seen as a constructive critic.' He added: 'I represent people who are not well off, old age pensioners, people who run businesses, and they've all got to pay their bills.

'Under current policy, we will fail on emissions targets, and we will fail to deliver a reliable energy supply.

'I think a large majority of Tory MPs will be sympathetic to what I'm saying.'