Nearly half of British homeowners are throwing away at least $160 (£100) in wasted energy payments every year because their houses aren’t adequately insulated.

The latest figures from the UK’s Department of Energy and Climate Change (DECC) show that only 57% of Britain’s lofts have been properly insulated and only 58% of cavity walls have been filled. Insulating lofts and cavity walls helps to reduce energy bills by cutting down on energy leakage.

“At a time when money is tight and with energy prices predicted to rise, householders are missing out on over £100 of savings every single year by not getting their lofts lagged and cavity walls filled,” said Chris Huhne, Energy and Climate Change Secretary. “We are making energy companies do more to help their hard pressed customers, with another 3.5 million households set to be protected against higher bills by the end of next year.”

Britain’s coalition government has told energy companies to increase their efforts to help people insulate their homes and save money. The government’s tougher Carbon Emission Reduction Target is expected to benefit a total of 3.5 million homes by December 2012.

Since adoption of the new target, some 479,000 professional insulation measures have already been installed, with more than three million more homes expected to be treated by the end of 2012. That averages out to more than 140,000 insulation measures a month.

Set to launch next year, the government’s Green Deal aims to help even more people improve the energy efficiency of their homes. The scheme will involve an extensive range of energy efficiency measures including installing insulation, replacing leaky windows, or upgrading inefficient old heating systems to the latest high-performing models. Homeowners will be able to invest in such improvements at no upfront cost and repay the costs through their savings on energy bills.

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