Developer Banks Renewables has broken cover as the source of the legal challenge to the UK government’s latest renewable energy auction as it contests the “needless prejudice” against onshore wind in the contract-for-difference (CfD) mechanism.

Banks Renewables said it has launched a judicial review process challenging the exclusion of onshore wind and other renewables from the latest CfD round, the schedule for which was this week pushed back as a result.

The exclusion of onshore wind and solar is a long-standing grievance of many in the UK renewables sector, who argue that the process unjustifiably favours offshore wind against potentially cheaper alternatives – especially land-based turbines, which apart from some exceptions on remote islands are banned from seeking CfD contracts.

Banks Renewables managing director Richard Dunkley said: “At a time when the UK Government has said it wants to accelerate its decarbonisation objectives, it would seem illogical to most people that, for the last four years, it has itself significantly undermined the deployment of the lowest cost low carbon technology available – onshore wind.

“We have consistently expressed the view for many years that, as the most cost-effective method of low carbon electricity generation available, consented onshore wind farms should be included within the CfD auction process, and we have been in discussion with the UK Government over this matter for several months.”

Dunkley said the government has shown no sign of shifting a policy introduced by the ruling Conservative Party when it came to power in 2015, leaving Banks “reluctantly” with legal action as its only option.

“We simply desire a level playing field, and believe consented onshore wind farms are legally entitled to participate in all CfD auction processes and to have an opportunity to access the aid necessary to construct consented sites.

“The exclusion of the onshore sector is clearly contrary to the open, transparent and non-discriminatory way in which the CfD scheme was expected to work,” said Dunkley.

“This legal challenge is very much a last resort and we hope it will be resolved as quickly as possible, but we firmly believe that changes are required to ensure the UK Government complies with its legal obligations and to end the needless prejudice within the CfD process against the most cost-effective and popular form of renewable energy generation.”

Banks Renewables operates 224MW of wind farms in northern England and Scotland.