Britain has one electricity price. So it pays wind farms to switch off.
When the wind in Scotland blows harder than the lines south can carry, a single national price doesn't reflect it. The system operator buys back the power it can't move instead. Here is one day of it, farm by farm and half hour by half hour.
Each circle is a wind farm, sized by its capacity; it fills with colour as it's paid to turn down, by the share of the farm turned down that half hour. Offshore farms are drawn in the sea, where they are. The bars are each half hour's wind turned down across Britain. Hover for a farm.
Why one price means paying to switch off
The day here is Tuesday 27 October 2026: 184 GWh of wind turned down and £7.15m paid to wind farms to do it, about £39 for each megawatt-hour they didn't make. Of what we can place on a farm, 99.8% was in Scotland, much of it at the big offshore farms in the Moray Firth and off Angus, and at Viking on Shetland. Britain's market sells power as if it could go anywhere at one national price. When it can't, because the lines from Scotland into England are full, the system operator pays Scottish farms to turn down in the Balancing Mechanism and pays other plant, often gas, further south to make up the difference. That second payment isn't in these figures.
How other places do it
New Zealand and Texas set a price at each point on the grid instead, so power behind a full line is simply cheap where it's made: see our New Zealand time-lapse. Britain chose to keep one national price in 2025 and is reforming the market around it instead; the cost of turning wind down is on our Curtailed page, every day, for every farm.
How this was made
Elexon's indicative accepted bid volumes and cashflows for every wind unit in each half-hour settlement period (BMRS data licence: contains BMRS data © Elexon Limited copyright and database right), the same figures our Curtailed page adds up by day; this day's totals match it. Units are matched to farms through the balancing units each farm is metered by; units we can't match still count in the totals and the bars. Paid is what wind farms received for bids at negative prices. A farm that bids a positive price pays the system to turn down instead, keeping what it had already sold, and that isn't counted as paid. The day is the one of the last 30 with the most wind turned down. Times are UK time, at the start of each half hour. Coastline: Natural Earth (public domain).
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