A Department of Energy and Climate Change (DECC) consultation document issued in October proposed to cut the FiT rate from 43.3p to 21p per kilowatt-hour for the smallest band of solar installations.
The claimants argued that DECC’s decision to cut rates from 11 December – almost two weeks before the consultation ends on 23 December – was unlawful. Today the High Court agreed that the proposals are unlawful.
Friends of the Earth executive director Andy Atkins said: "These botched and illegal plans have cast a huge shadow over the solar industry, jeopardising thousands of jobs.
"We hope this ruling will prevent Ministers rushing through damaging changes to clean energy subsidies, giving solar firms a much-needed confidence boost.
"Ministers must now come up with a sensible plan that protects the UK's solar industry and allows cash-strapped homes and businesses to free themselves from expensive fossil fuels by plugging into clean energy."
"Solar payments should fall in line with falling installation costs, but the speed of the Government's proposals threatened to devastate the entire industry."