The government's flagship programme to transform the energy efficiency of 14m homes in the next decade will fail and only reach only 2-3m households, according to an unprecedented attack from the government's own climate advisers.
The warning comes from the Committee on Climate Change (CCC), which on Tuesday for the first time published an open letter criticising government policy. It follows soaring energy bills and the news that one in four homes are now in fuel poverty.
The "green deal" plan, which will start in October 2012, will allow homeowners to take out loans to pay for insulation, with the guarantee that the savings on their energy bills will be greater than the loan repayments. Currently, energy companies have a legal obligation to enable their customers to improve their energy efficiency.
"The [green deal] proposal is to take away that obligation and say 'let's leave it to the market'," said David Kennedy, the CCC chief executive. "We think there is a significant risk in leaving it to the market, as that has never worked anywhere in the world and is unlikely to happen in the UK. We are talking about the transformation of the entire building stock of this country."