An estimated 15,000 people died unnecessarily between December and March because they were living in homes they couldn’t afford to heat, new figures show.

The news has led campaigners to hit out at what they claim is an inadequate Conservative pledge to help freezing people by insulating homes.

Fuel poverty campaigners reckon the number of excess winter deaths surged last winter to 49,260, of which around 14,780 were due to people living in cold homes.

The Energy Bill Revolution estimates that the average number of excess winter deaths over the previous five years was 27,830, so last winter saw an increase of 77 per cent above the five year average.

But ahead of next week’s election, the campaigners hit out at Tory pledges to insulate just 1 million homes if they win the election.

Ed Matthew, director of the Energy Bill Revolution, said the pledge would represent an 80 per cent decline in the rate of home insulation compared to the last Parliament when 5 million homes were insulated.

“The Conservative pledge is shocking,” Mr Matthew said. “It would lead to a crash in the delivery of life-saving insulation measures and leave millions of people to freeze in their homes. Given most fuel poor are working families this strikes me as an election own goal.”

All the other major parties - Labour, Liberal Democrats and Greens – have made pledges in the lead up to the election to fund far more ambitious and effective home energy efficiency programmes to end the cold home crisis, he said.

The new figures follow research published two weeks ago that revealed that some 14.3 million households turned off heating at some point last winter to cut energy bills.

Some two-fifths of consumers said they left their oven door open after cooking and a quarter wore a coat, scarf or hat indoors to keep warm rather than turning on their heating, according to the uSwitch survey.

Ann Robinson of uSwitch, said: “It’s unacceptable that people should feel forced to gamble with their health to try and cope with sky-high energy bills.”

Making the homes of the fuel poor energy efficient is the most effective way to combat cold home deaths, reduce energy bills and bring them out of fuel poverty, says Energy Bill Revolution.

It has demanded that investment in making homes highly energy efficient be made a UK infrastructure capital spending priority.

Mr Matthew pointed out that the UK Treasury plans to spend £100 billion of public money on infrastructure over the course of the next Parliament. “Investing just 3 per cent of the budget in making homes highly energy efficient, alongside existing energy efficiency budgets, can bring two million UK low income homes up to a high standard of energy efficiency by 2020. All six million low income homes should be brought up to this standard by 2025.”

Such a move would not only cut cold home deaths, it would slash energy bills and carbon emissions, create more 100,000 jobs and helping end fuel poverty. It would also reduce costs for the NHS, Mr Matthew said.