The Scottish Wind Farms That Get Paid to Switch Off

Twenty-seven miles off the Angus coast, Britain's biggest offshore wind farm spends a lot of its time doing nothing.

Seagreen, at 1,075 MW, was the single most curtailed wind asset in Britain in 2025, with 2.7 terawatt hours of potential generation turned away. Independent estimates put its curtailment rate at roughly 66 per cent. Two thirds of the time, the wind is blowing and the turbines are told to stand down. Modo EnergyUKERC

And here is the strange part. The owners get paid for it.

The short answer: Scotland generates more wind power than the cables to England can carry. When that happens, the grid operator pays Scottish wind farms to switch off, then pays gas plants in the south to switch on and fill the gap. In 2025 the total bill came to £1.46 billion, with £380 million going to wind farms for turning down and £1.08 billion spent replacing the lost power, usually with gas. You pay for all of it through your electricity bill. Bitcoin miners think they can soak up some of that wasted energy, and in Texas they already do. National Wind Watch

A billion and a half pounds for nothing

The payments are called constraint payments, and they are not small change.

In the first two months of 2025 alone, they cost £252 million, roughly £178,000 an hour. Back in 2020 the annual figure was around £282 million. By 2025 it was £1.46 billion, and Octopus Energy has warned it could hit £8 billion a year by 2030 without reform. Britain paying £180,000 an hour to switch off wind farms +2

This is overwhelmingly a Scottish story. An estimated 98 per cent of curtailed wind generation is Scottish, and the biggest, newest farms are hit hardest. Seagreen, Viking on Shetland and Moray East, three flagship projects, show curtailment estimates of 66, 60 and 38 per cent respectively. Tim HarperUKERC

The money is real, and so is the waste. Between January and November 2024, 6.6 terawatt hours of wind power was curtailed, up from 3.8 terawatt hours in all of 2023. That is roughly enough electricity to power every home in Scotland for most of a year, generated by nobody and paid for by everybody. MARA

Why the grid pays people to stop working

The problem is not the wind. It is the wires.

Britain built its grid for a world where power stations sat near cities. Then it built its wind farms where the wind is, which is mostly the north of Scotland and the seas around it. The demand, though, is mostly in England.

The cables connecting the two can only carry so much before they overheat, so on windy days the grid operator turns wind farm output down in Scotland, because the power cannot safely be exported south, and replaces that energy in the south, typically with gas. UKERC

That is the double payment. Wind farms receive curtailment payments for shutting down, while grid operators simultaneously pay gas plants to produce replacement power. Pay one side to stop. Pay the other side to start. Send the bill to households. Ofgem says constraints added about £15 to a typical annual bill, and the fix is not cheap either: the regulator has approved around £70 billion of network upgrades over five years, which it expects to add roughly £60 to bills by 2030. How Much is Clean Energy Curtailment Costing UK Consumers? | Sustainability Magazine +2

The new cables will help. But they arrive at the end of the decade, and Clean Power 2030 targets call for 20 GW of Scottish wind generation, so generation keeps growing while the wires catch up. In the meantime, an enormous amount of clean energy has nowhere to go. Modo Energy

Which brings us to the shipping containers.

Enter the machines that eat spare electricity

A Bitcoin mine is not a glamorous thing. It is a metal box full of specialised computers, fans roaring, doing one job: guessing numbers to secure the Bitcoin network in exchange for newly issued Bitcoin. Park it next to a power source and it converts electricity into money, anywhere, at any hour.

What makes miners unusual is not that they use a lot of power. It is that they do not care when they get it. Mining rigs can scale up and turn on instantly when there is excess production, and shut down when demand returns. Almost no other industrial customer can do that. A factory cannot run only on windy nights. A metal box of computers can. CryptoNexa

So miners have started turning up wherever energy is stranded. In 2022, Bitcoin miners in West Texas consumed 1.3 terawatt hours of otherwise curtailed wind energy, generating 60 million dollars in revenue for wind farms. In 2024 the American mining firm MARA went a step further and bought a Texas wind farm outright, with 114 MW of active generation, to mine with electricity that would otherwise have been curtailed. SazminingCfC St. Moritz

Closer to home, researchers have run the numbers on Irish wind, which faces the same problem as Scotland. One peer-reviewed study modelled a 100 MW Irish wind farm and found that co-locating 20 MW of Bitcoin mining raised the farm's revenue by 32 per cent, absorbing 83 per cent of the energy that would otherwise have been turned away. ScienceDirect

The logic for a Scottish turbine owner is the same. Instead of being paid to produce nothing, sell the trapped electricity to a buyer standing in the field next door. Advocates argue that Bitcoin mining is the only technology offering completely elastic demand for spare renewable energy, setting a floor price for supply that would otherwise be curtailed at cost, without requiring subsidies. CryptoSlate

The honest caveats

This is not a magic fix, and it is worth being straight about why.

First, mining next to a turbine does not remove the constraint payment system. That is set by how the grid market works, and changing it is a policy question. Second, miners running only on surplus wind sit idle when the wind drops, which stretches the payback on their hardware. And it remains unclear whether Bitcoin's price volatility would make these returns dependable. CryptoNexa

The strongest version of the argument is narrower: while Britain waits years for new cables, a flexible buyer that monetises wasted clean energy makes wind farms more viable and wastes less of what we have already built. The weakest version, that mining alone solves the grid, is hype, and we do not do hype.

Where this lands

Every wasted terawatt hour off the Scottish coast is a reminder that energy and money are tangled together. Bitcoin's critics call its energy use a bug. Its supporters point at Seagreen's idle blades and call flexible demand a feature. Both sides agree on one thing: the machines keep turning up next to the turbines, because that is where the cheap electrons are.

If you want to understand what those machines are actually building, start with our beginner's guide, [WTF is Bitcoin]. If you run a company and you are wondering what any of this means for you, [Bitcoin for Business] is written for exactly that. And for one email a week cutting through stories like this one, join the [weekly newsletter].

This article is for education, not financial advice.

FAQ

What are wind farm constraint payments?
Payments made to wind farms to reduce or stop generation when the grid cannot carry their power. The grid operator then pays other generators, usually gas, to produce replacement power nearer to demand. Sustainability Magazine

How much do constraint payments cost the UK?
Total constraint costs reached £1.46 billion in 2025, and Octopus Energy warns they could reach £8 billion a year by 2030 without reform. National Wind Watch

Why is most curtailed wind in Scotland?
Scotland has the wind and the wind farms; England has most of the demand. The transmission boundaries between them were constrained for large parts of the year, so Scottish output gets turned down first. Modo Energy

Can Bitcoin mining really use curtailed wind power?
Yes, and it already happens elsewhere. Texas miners consumed 1.3 TWh of curtailed wind in a single year, and modelling of Irish wind farms found co-located mining absorbed 83 per cent of dispatch-down energy. In the UK it remains early and largely untested at scale. SazminingScienceDirect

Do constraint payments affect my energy bill?
Yes. Ofgem estimates constraints added about £15 to a typical annual household bill. National Wind Watch