By Ian Lewis
Renewable energy experts have criticised government plans to water down a move to make all new-build homes "zero-carbon".
The last Labour government pledged to make sure all new homes were highly energy efficient from 2016.
Ministers had said they would implement the requirements from 2016, but the newly-announced Infrastructure Bill will enable builders to avoid building zero-carbon homes by funding off-site alternatives instead.
The Bill also exempts small building sites from the requirements, with the government claiming it isn't always possible or cost-effective to build fully reduced-emission homes.
Energy bills under £300
But experts in the renewables industry say this throws up the prospect of buyers having to pay for the cuts in carbon emissions without getting the benefit of lower energy bills.
The Renewable Energy Association's (REA) chief executive, Dr Nina Skorupska, said: "Imagine energy bills under £300. That's what energy efficiency and renewable technologies, like solar panels, wood fuel boilers and heat pumps, can offer.
"But the government is so desperate to get lots of houses built quickly that they seem blind to the opportunity to give these new homes super-low energy bills.
"Instead, the occupants will probably have to foot the bill for the new tax."
'Zero-carbon homes save a fortune'
Meanwhile, the UK Green Building Council's chief executive, Paul King, said: "The coalition will laud their green credentials by claiming to have delivered on the promise for all new homes to be zero-carbon from 2016.
"This has undoubtedly been hard-won by the Lib Dems, but unfortunately they are at risk of snatching defeat from the jaws of victory by letting small developments - a large chunk of the house building market - off the hook.
"Zero-carbon homes save a fortune for households in energy costs and are better for the environment."
The government has also announced plans to increase house building. They include legislation which will enable a garden city to be built at Ebbsfleet in Kent.