Labour accused ministers of making another U-turn as they finally agreed to cap prices charged by wind farms and nuclear power stations.
Ed Miliband said the Tories had been “dragged kicking and screaming” to introducing a limit on the money that can be made by electricity firms.
Renewable energy generators and nuclear plants will have their revenues capped under a new Government plan to ensure they are not benefitting from record-high energy prices.
As gas prices have soared over the last year, the price of electricity has also gone up meaning many of Britain's wind farms and solar farms were paid a lot more than normal for their products, even though their costs had not increased very much.
Without releasing much detail, the Government said it would try to break the link between high gas prices and the amount made by electricity producers.
Announcing the move tonight, Business Secretary Jacob Rees-Mogg said: "Businesses and consumers across the UK should pay a fair price for energy.
"With prices spiralling as a result of Putin's abhorrent invasion of Ukraine, the Government is taking swift and decisive action.
"We have been working with low-carbon generators to find a solution that will ensure consumers are not paying significantly more for electricity generated from renewables and nuclear."
The Government said it planned to introduce a price limit, but provided little detail about how this would work.
Mr Miliband, who is Labour 's Shadow Business Secretary, said ministers had “finally accepted the principle of Labour’s call for a windfall tax on excess profits of electricity generators”.
He added: “After months of telling the country they were utterly opposed to the principle of a windfall tax, they have been dragged kicking and screaming to implement it.
“Yet again this shows Labour leading the agenda in British politics with another screeching U-turn from a government in office but not in power.
"But the Government’s delay in acting will have cost billions and the public will pay the price.”
