The sun has set on DECC’s plan to cut the solar Feed-In Tariff after the Supreme Court ruled it could not appeal against a previous judgement.

At the end of last year DECC wanted to halve the FiT for solar panels installed after 12 December, two weeks before the end of a consultation into cutting the subsidy.

Two solar firms and campaign group Friends of the Earth teamed up to bring a lawsuit against the department over the cut. They claimed it would damage the fledgling solar industry because it could potentially mean DECC could change how much people were paid for producing solar energy under the FiT when they had already built the panels.

In late December and then at the end of January two courts both ruled in their favour, finding DECC’s action “unlawful”.

DECC disagreed and asked the Supreme Court for permission to challenge the judgements, but today the Supreme Court upheld the decision that it was not in the Energy Secretary’s power under the Energy Act 2008 to cut the subsidies in such a way.

Now all solar PV installations built between 12 December and 3 March will get the higher tariff rate of 43.3p/kWh (for up 4kW in size) for the next 25 years.

This is instead of the lower tariff rates now in place, which are 21p/kWh.

The Solar Trade Association hailed the end of a “turbulent” few months for the industry.

Chief Executive Paul Barwell said: “This marks the end of this particular turbulent chapter for the UK solar sector. We welcome the certainty for those who invested and installed since 12th December.”

Responding to today’s decision Energy Secretary Edward Davey said: “We are disappointed by the decision of the Supreme Court not to grant permission to hear this case.  But the Court’s decision draws a line under the case.  We will now focus all our efforts on ensuring the future stability and cost effectiveness of solar and other microgeneration technologies for the many, not the few.”