Energy bills will account for up to 10% of the average salary from April, new research suggests.
The TUC said its analysis found the average energy bill will rise to £250 a month, more than double the amount workers were paying a year ago.
The union organization urged the government to create a public energy company to reduce bills, saying low-paid workers were the most affected.
A full-time minimum wage worker will face bills worth 16% of his monthly salary when the maximum price is raised in April, up from 8% in March 2022, the TUC said.
He repeated his calls for a higher windfall tax for big oil and gas companies and urged ministers to end “Britain’s standard of living nightmare”.
The TUC claimed the UK energy market has become a “gimmick” with oil and gas companies raking in billions in profit while families struggle to heat their homes.
TUC General Secretary Paul Nowak said: “The government must write off its impending rise in household energy bills in next month’s budget. Families across Britain are being pushed to the brink by sky-high bills.
“That means imposing a higher windfall tax on greedy oil and gas suppliers, and it means raising wages throughout the economy.
“UK workers are on track for two decades of lost wages. This has left millions brutally exposed to sky-high prices.
“Unless we raise wages, workers will continue to lurch from one crisis to another.
“Our energy market has become a racket. It is time for companies to return to public ownership.
“Privatization has been a disaster for struggling households. The only real winners have been the shareholders who have made hundreds of millions in dividends.
“That’s why the TUC asks the government to create a public energy company to lower bills.”
Shadow Climate Secretary and Labor MP Ed Miliband said: “Within a matter of weeks, Rishi Sunak plans to allow the maximum energy price to rise to £3,000.
“At the same time, the oil and gas giants are taking the windfall of war, and Rishi Sunak’s conservatives refuse to implement a proper windfall tax that would make them pay their fair share.”
He said Labor would use a “proper windfall tax to prevent prices from rising in April.”