Scotland’s renewables industry is warning that a charging system designed for a very different energy era is now actively working against the UK’s clean power ambitions.

A new report from Scottish Renewables is calling on Ofgem to move immediately on reforming transmission network charges, arguing that the current system is deterring investment, destroying value for consumers and putting Scotland’s role in Britain’s future energy mix at risk.

At the heart of the problem are Transmission Network Use of System charges, the fees generators pay to access and fund the electricity grid.

Designed more than 30 years ago, the regime is volatile, unpredictable and badly misaligned with the government’s Clean Power 2030 mission.

Instead of rewarding renewable generation located close to abundant resources, it penalises Scottish projects with some of the highest charges in Europe.

Since 2015, existing Scottish generators have faced £2.9 billion in unforeseen and unavoidable increases in network charges. Those costs ultimately flow through to consumers while making Scottish projects less competitive, less investable and in some cases unviable.

The report warns that without urgent interim reform, the problem will intensify. Projects that could have delivered jobs, supply chain growth and clean power have already failed to secure support through Contracts for Difference auctions, because of exposure to unpredictable future charges. More are likely to follow.

Scottish Renewables is urging Ofgem not to wait for a full redesign of the charging regime but to act now.

For existing assets, it wants generators given the option to fix charges at a known level over the life of a project, based on forecasts that applied at the point of final investment decision. For new projects, developers should be able to lock in network charges at the level in place when they bid into CfD auctions, rather than rely on long-term forecasts built on a flawed methodology.

Claire Mack, CEO of Scottish Renewables, said the consequences of delay are already visible. “It has been clear for some time that the current transmission charging regime is not fit for purpose and we have now seen projects, jobs and supply chain opportunities lost as a direct result.”

She said the regulator and government must now align network charging with a reformed electricity market that supports decarbonisation at best value for consumers.