A plan to weaken the link between electricity prices and the gas market has been unveiled by the UK government.

Energy Secretary Ed Miliband and the Chancellor Rachel Reeves want to protect consumers from supply chain shocks such as the outbreak of conflicts.

Under the plan, older renewable energy generators would move to fixed-price contracts, avoiding the variable price of gas.

The government also says that “excess profits” made by some electricity generators will be taxed at 55% from 1 July, up from 45%. This so-called windfall tax will be extended beyond 2028, when it had been due to expire.

The plan represents a doubling down on renewables, rather than a restart for fossil fuels which oil and gas supporters have demanded.

“For Britain and so many other countries, clean energy is now the only route to financial security, energy security and national security,” Mr Miliband said.

He argues that the war in the Middle East, and the need to tackle climate change make the focus on renewables such as wind, solar and hydro more important and that the UK should go faster in pursuit of net zero goals.

However, tackling the sources of supply that underpin electricity output when the wind is not blowing is vital. In Britain that is gas and nuclear.

A key blockage to translating an increase in wind output into lower bills is that the price of electricity is set by the last unit of electricity needed to meet demand at any given time. In Britain, that last unit is often gas – which means that when gas prices spike, so do electricity bills.

Britain has already moved from gas setting the price of electricity around 90% of the time in the early 2020s, to around 60% today. Through the government’s clean energy mission, it is estimated gas will set the wholesale price around half of the time by 2030.

Revamping the entire system has been set aside for now in favour of fixing the price.

Prime Minister Keir Starmer said: “We need to get off the fossil fuel rollercoaster – this will make energy bills more stable and take the pressure off family budgets. When global gas prices spike, people here shouldn’t be picking up the tab.

“Our focus is simple: easing pressure on household budgets now, while building a homegrown energy system that protects families from global instability in the years ahead.”

Energy Secretary Ed Miliband said: “As we face the second fossil fuel shock in less than 5 years, the lesson for our country is clear: The era of fossil fuel security is over, and the era of clean energy security must come of age. That’s why we’re doubling down on clean power, to give our country energy security and bring down bills for good.

Chancellor Rachel Reeves said: “Hardworking British families and businesses should not bear the brunt of global gas price shocks while electricity generators are making exceptional profits.

“Alongside moving generators onto the competitive pricing assured through wholesale Contracts for Difference, increasing the EGL to 55% will help to break the link between high gas prices and high electricity prices – offering households and businesses stronger protection against future energy shocks.”

Opponents claim the plan does not go far enough.

Shadow energy secretary Claire Coutinho pointed to taxes and levies on bills on top of wholesale prices.

“If we want people to use electricity, then we need to make it cheap,” she said.

In his manifesto speech last week, SNP leader John Swinney said: “In energy rich Scotland, people can’t afford to heat their homes. the problem is not that we don’t have the energy.

“The problem is that Westminster has the power. This election is our opportunity to take those powers and put them into Scotland’s hands.”

Liberal Democrat energy spokesperson Pippa Heylings said the government should act and break the link between electricity and gas prices.

“We have consistently argued that if Britain is generating more and more cheap renewable electricity, households should feel the benefit in lower bills,” she said.

Green Party energy spokesperson Carla Denyer said she was “relieved” to hear the plans but accused the government of being too slow to act.

Angharad Hopkinson, political campaigner for Greenpeace UK, said: “Britain is sick and tired of an energy system where pump prices and household bills go up and down based on Trump’s latest social post or the Persian Gulf opening and closing like an umbrella in April.

“The government is absolutely right to be looking at every possible solution to cut our dependence on volatile fossil fuels and take back control of our energy. 

“It’s obvious that consumers haven’t been taken in by the oil industry’s propaganda. People in Britain still support the transition, both in principle, as shown by polling, and practice, as shown by the boom in EVs, home solar and other clean tech.”