Decc said improvements had been made to the proposals for the subsidies in the future, including lowering the level of energy efficiency housing must have to qualify for payments, as the previous tougher proposals were "impractical." And officials would be examining whether community and housing association projects should be exempt from a reduced rate for schemes which claim the tariffs for a series of installations. The reduced rate aims to take account of the lower costs of bigger projects and curb excess profits made by companies who install panels on people's homes and then claim the payments while the householders see a reduction in bills. Under the new plans unveiled today the rate will apply only to schemes with 25 or more sets of solar panels. The Department also said the overspend on the budget will be met by money from underspending on large-scale renewable subsidies, for example for offshore wind. Mr Barker, responding to a move this week by Conservative colleagues urging David Cameron to cut subsidies for onshore wind power, said while there were concerns about turbines in some locations, the Tories were enthusiastic about solar and decentralised energy. But while a new consultation on other types of small-scale renewable, also published today, proposes raising the payments for micro-combined heat and power boilers, it also sets out plans to cut small-scale wind and hydro scheme payments. Green MP Caroline Lucas said the new Lib Dem Energy Secretary Ed Davey should have delayed the solar policy change and got it right, warning that the proposals could see tariffs reduced as often as every two months. But today's announcement once again leaves the industry reeling, with tariff cuts going far deeper than the falling costs of installation warrant. While the Government sounds ambitious in its aims, the actual policy looks weak - with ministers giving themselves the option of changing the tariff every two months. The one thing that business needs is certainty, yet these Government cuts are being made so fast that it is destabilising the industry. The proposed tariff cuts also go deeper than the falling costs of installation should warrant.