Great Britain system warnings from NESO
Check the latest recorded Great Britain capacity declarations, their stated levels and the days affected this year. Read the source postings, then open the grid map to investigate operating conditions.
See it on the live Great Britain map, updating as the market publishes.
Explore Great Britain grid conditionsAbout this view
Great Britain's ladder
NESO issues an Electricity Margin Notice to ask the market for more margin, which it states is not a shortage. A High Risk of Demand Reduction warning follows if margin may not cover demand, and Demand Control Imminent when disconnection is expected within the hour. Negative Reserve Active Power Margin warnings, usually for one Scottish region, say there is too little room to turn generation down.
How the days are counted
A day counts when a capacity declaration at alert or above covers any part of it, in the market's own time zone, whether it covered the whole footprint or one region. Each day takes the highest step and NERC EEA level declared that day, and overlapping or renewed postings count once. Drills are never counted.
One ladder across markets
Every operator names its steps differently. Ask the Grid places each on one ladder, advisory, alert, warning, emergency action and load shed, with the NERC EEA level the operator states or its procedure defines, so a day here means the same thing in every market.
Questions
Has NESO issued a system warning this year?
The counts at the top of this page say, with each day a warning at alert or above was in force. They come from NESO's own notices and update within minutes of a new one.
Does an Electricity Margin Notice mean blackouts?
No. NESO uses it to ask for more margin between supply and demand in the hours ahead, and says so in every notice. A demand reduction warning is the step that says margin may not cover demand.
Why is there no EEA level?
Energy Emergency Alert levels are a North American (NERC) scale. Great Britain's warnings are defined by its Grid Code, and Ask the Grid places them on the same ladder without claiming an EEA level.
How far back does this go?
From the first NESO warning Ask the Grid recorded. Days before it are not counted.