Great Britain transmission boundaries: flow against limit
NESO publishes the flow it expects across each constraint boundary and the limit it can carry, half-hourly, a day ahead. Boundaries are ranked by loading for the period in force.
See it on the live Great Britain map, updating as the market publishes.
Explore the Great Britain network on the mapAbout this view
What a boundary is
A boundary is a cut across the network that NESO monitors as a group, named by its code. Loading is the flow as a percentage of the published limit.
Where there is no limit
NESO publishes 10,000 MW on a boundary it does not limit. Those boundaries show flow alone, with no loading percentage.
A day-ahead publication, with no price
These are day-ahead flows and limits. They carry no shadow price, so this view ranks loading rather than the cost of congestion.
Questions
Is this a real-time constraint feed?
No. It is NESO's day-ahead publication for the period in force.
Why is there no price?
NESO publishes flow and limit only. Constraint costs are settled separately.
What does a boundary with no loading figure mean?
NESO publishes 10,000 MW where it sets no limit, so only the flow is shown.