Green campaigners have accused the Conservatives’ of “living in fantasy land” after the party laid out plans to ditch net zero and prioritise cheap energy over decarbonising Britain’s power grid.

The shadow energy secretary Claire Coutinho revealed her party’s case for planning to ditch net zero in a speech on Wednesday, insisting the UK “should focus all our attention on making electricity cheap, and then let consumer choice be king”.

A report commissioned by the Conservatives, written by Tory-leaning think tank Onward and advisory firm Transira Energy, suggested focusing on cheap power could save families £540 a year from their energy bills.

But green campaigners have said the proposal is “completely out of touch with the public, its own voters, and economic reality”, while others branded the claims a “myth” that would require a “mathematical miracle”.

“After thousands of deaths from extreme heat this summer, this announcement shows the Conservative Party is completely out of touch with the public, its own voters, and economic reality,” Friends of the Earth energy campaigner Danny Gross said.

“Clean power is the route to cheap, secure energy, not a barrier to it. Home-grown wind and solar energy are cheaper and less exposed to global price shocks than gas. The Conservative plan would just leave the UK more exposed to volatile fossil fuel markets in the future.

“Anyone who thinks doubling down on new North Sea oil and gas projects will bring down energy bills is living in fantasy land. The only way to cut our energy costs is to reduce our reliance on expensive oil and gas.”

Greenpeace branded the proposals a “myth”, which flies “in the face of all the real-world evidence, both on climate and economics”.

“It is a myth that gas is cheaper than renewables,” Angharad Hopkinson, political campaigner for Greenpeace UK, said.

“One big gas price spike from a war or other major disruption costs Britain more than the entire net zero project.

“We saw the economic risk of dependence on fossil fuels when the wars in Ukraine and Iran sent energy bills skyrocketing. When a political party that receives lots of fossil fuel money says you should switch from the cheapest electricity sources to the most expensive, exercise caution.

“When they claim huge overall savings, best wait until some independent experts have a look before you start celebrating the mathematical miracle.”

James Sutton, Co-Executive Director of Zero Hour, said the government must “stay strong” and stay committed to renewables.

“The Conservatives might want us to forget 2022, but families will still remember the difficult choices they were forced to make when their bills shot up at the hands of a fossil fuel driven energy crisis,” he said.

“The price of electricity is high precisely because it is tied to the volatile price of gas. Yes, Britain needs control of its own energy. But doubling down on the North Sea or fossil fuels does the exact opposite. It locks communities into a future where household bills are dictated by global politics and conflict, and the only winners are oil and gas giants’ profits margins.

“It’s been proven time and again that fossil fuels are bad for bills, bad for the environment, and bad for our energy security. The Conservatives once understood that.

“The government must stay strong and do what is right for people - commit fully to renewables and keep household energy bills down”.

Reaching net zero by 2050, the policy aimed at balancing out the amount of greenhouse gases with those being removed from the atmosphere, was introduced by the Conservative government under Theresa May in 2019.

Ed Miliband continued the drive towards net zero as energy secretary, followed by Miatta Fahnbulleh, since Labour came into power – and the party is aiming to make the grid 95 per cent carbon-free by 2030.

But Kemi Badenoch has declared the 2050 target is impossible to meet, has vowed to scrap the policy, and is blocking Conservatives who support net zero from standing as parliamentary candidates in the next general election.

In her speech, Ms Coutinho said Mr Miliband is “intent on squeezing every last drop of carbon out of our electricity, no matter the cost”.

She added: “There are some who will say that the cost is worth it because it gives us climate leadership, but our high electricity prices are not convincing any other countries to follow our lead.

“In fact, it’s our hot and heavy pursuit of net zero that is giving the others ‘the ick’.”

She continued: “The truth is that too much wind and solar creates all of these extra hidden costs.

“It’s like a Ryanair flight. The ticket might look cheap, but once you’ve paid for a bag, a seat and a sandwich, you realise you’ve been stung.”

Ahead of the speech, Conservative leader Mrs Badenoch said: “Britain needs a serious plan to deal with climate change. Seriousness means looking at results, not simply setting targets and congratulating ourselves afterwards.

“Current Net Zero targets have driven up energy costs, weakened our industrial base, and made us more dependent on energy imports, while doing too little to make the country more resilient to floods, droughts, and other consequences of the changing climate.

“This report shows what a common sense approach looks like. Unlike Labour, who are wedded to the old failing plans; or Reform, who still don’t believe climate change is happening, the Conservatives will protect our environment, protect our energy security and make energy cheaper. Our plan means using our own oil and gas in the North Sea, removing unnecessary costs from energy bills, and backing cheap, reliable, abundant energy for homes and businesses.”

But Labour accused the Tories of “following Reform’s lead” in their policy direction on oil and gas, which they said would “tie Britain to the fossil fuel rollercoaster and keep bills higher for families.”

Energy secretary Ms Fahnbulleh said: “Labour is investing in more clean energy jobs, cutting tax on electricity bills to give families breathing space this winter and we’re taking action to tackle the climate crisis and bring down bills for good. Kemi Badenoch would put jobs at risk and increase bills.

“As global fossil fuel prices continue to rise amid conflict overseas and wildfires rage across the UK, we can’t turn our back on clean power. That won’t bring down bills and it won’t address the climate crisis. The Tories don’t have a clue.”