Martin Lewis, backed by some 95 charities, has urged the government to look at energy social tariffs ahead of the Budget next Wednesday, 15 March.
A social tariff could help over 12mln low-income households save up to £1,500 each, according to Citizens Advice, which joined the calls alongside Lewis, claiming it would also be affordable for the government.
HMRC’s real-time data of household incomes, partnered with energy suppliers’ knowledge of usage, could allow the two to see who and how people needed help, it explained.
Many of these people are not currently offered support, the charity explained, since they are not claiming benefits.
A social tariff, already offered by broadband companies for customers on certain benefits, would see people in need granted cheaper bills through subsidies capping how much they are charged per unit of energy.
Ofgem determines how much suppliers can charge for electricity and gas, while the government’s Energy Price Guarantee governs how much people actually pay.
Since government support is set to be scaled back from April, households will likely face growing energy bills, despite the wholesale cost - governed by gas - having fallen recently.
“I’ve argued for a social tariff for years, and now it could be a crucial building block to help repair our broken consumer energy market,” Lewis said.
He added there “were two main routes” to fix the market - tougher regulation on pricing or increasing competitiveness among suppliers so customers could switch to better deals.
These, though, could only be addressed when the country returns “to a more normal situation,” following excessive price rises sparked by Russia’s invasion of Ukraine.
“We must be blunt and identify who are the legitimate and who are the illegitimate victims of competition,” he said.
“If I, as a wealthy, financially educated person chose not to switch, that’s my problem. If a struggling low-income 90-year-old grandmother with onset dementia doesn't switch – that’s all our problem.
“A social tariff looks to protect those who need it.”
Calls for the tariff grew after Which? found seven in ten people had put off heating their homes to combat rising bills, while many had also skipped meals and prioritised feeding others.
Citizens Advice added uninsulated homes were also causing people to waste money on bills, urging the government to kickstart a national effort to solve this, calculating it would cost £1.1bn, but save over a million billpayers up to £561 a year.