NESO managed up to 4.9 GW of wind through storms Austen and Boelo

Serguey Asael Shinder28 October 2026, 09:131 min read

Great Britain's electricity system operator says the national system stayed secure, with healthy operating margins, through storms Austen and Boelo, which hit over the weekend before its 26 October update. Storm Boelo brought gusts above 80 mph in exposed areas. Demand exceeded 33 GW while transmission circuits suffered repeated storm-related faults, and restoration in the Western Isles was slowed by the continuing weather.

NESO says that at times up to 4.9 GW of wind generation had to be actively managed to keep the system secure, while additional generation was brought forward for resilience and stability. In northern Scotland it identified a potential 70 MW shortfall in flexibility and issued a Localised Negative Reserve Active Power Margin (NRAPM) notice, asking generators in that part of the network to make more flexibility available; they did. It also issued an emergency instruction to one generator for 50 MW to balance the system.

The operator distinguishes the national picture from the local one: power cuts and flooding affected communities, and distribution network teams were still repairing assets and restoring supplies when the update was published.

What it means

The figures show where a storm strains a high-wind system: not total supply, but the ability to turn generation down in the right place when lines trip. A 70 MW gap is small nationally and decisive locally, which is why the tool used was a localised notice rather than a system-wide one. "Secure" in this report describes the transmission system; it does not mean customers kept their power.