Scotland’s largest operational offshore wind farm, the Seagreen project (1.075 GW capacity, 114 turbines, operated by SSE Renewables and TotalEnergies), reportedly wasted around 77% of its generated electricity in 2025 due to grid constraints.

This means operators were paid to curtail (switch off) turbines when the UK grid- particularly transmission lines from Scotland to higher-demand areas in England- could not handle the surplus power.

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Lack of grid capacity means operator cannot transport electricity to much of the country

The Seagreen wind farm off Scotland’s east coast is squandering vast amounts of its power because there is not enough grid capacity to transport it to areas of the country where it is needed most.

This inability to handle surplus electricity led to 77% of Seagreen’s total output going to waste last year, new accounts show, from a total of 114 turbines. The Telegraph has the story.

This is likely to have sparked hundreds of millions of pounds in so-called constraint payments for the wind farm, which is run by Scottish energy giant SSE and France’s TotalEnergies.

These payments are made under a Government scheme to encourage renewables, aimed at guaranteeing cash for green power even if it cannot be used.

SSE, which is the lead partner in the Seagreen wind farm, refused to disclose how much it was paid for switching off the turbines.

However, estimates from the Renewable Energy Foundation suggest it could amount to more than £200 million for the year.

Constraint payments relating to wasted wind are added to consumer and business energy bills in the form of network charges.

Overall, they totalled around £1.7 billion last year and are set to reach £8 billion by 2030.

Claire Coutinho, the Shadow Energy Secretary, blamed Ed Miliband, the Energy Secretary, for overseeing a system that is becoming unaffordable.

“What other sector do we pay people not to produce anything? We’re spending £1 billion switching wind farms off today, but thanks to Ed Miliband’s mad dash for renewables, we’ll be spending £8 billion by 2030,” she said.

“We simply cannot afford an approach that makes our energy system higher cost and less productive. Cheap, reliable energy must come first.”

Seagreen became operational in October 2022 with 114 turbines having a theoretical capacity of one gigawatt, although fluctuating wind power means effective capacity is less than half this figure.

Read the full story here.

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Scotland has abundant wind resources but limited interconnector capacity southwards (e.g., the B6 boundary bottleneck).

When wind generation exceeds local demand and export limits, the National Energy System Operator (NESO) curtails northern wind farms and ramps up southern generation (often gas plants), leading to inefficiency.

This is a known issue across UK renewables: rapid wind farm deployment has outpaced grid upgrades.