Fills every monitoring point (teal ring, navy centre): SSE grid substations, pulsing = live feeder readings; SPEN metering points on the boundary circuits, history to 31 Jul 2026. No cable on the map has live metered flow published.
Key
Local Cluster
Vicinity Cluster — NnG, Dun Law, Toddleburn
B6 - Non Local
North of B4/B5
400kV 275kV 132kV HVDC Offshore wind connection
Constrained corridor: NESO flow over limit, or (feed offline) 100MW+ wind bid off just behind the boundary
Substation, size = MW bid off at connected wind farms
SSE / SPEN Flow Data (SSE up to T+18 mins; SPEN T+10 weeks) Network monitoring points. Pulsing = SSE live feeder readings (20 grid substations); still = SPEN boundary circuits, history only.
SSE - Live Cable Curtailment (data unavailable in SPEN) Red point and glowing cables: wind being bid off within 30 km of an SSE monitoring point now.
Trigger zone bid off vs E-Boiler accepted, last 8 hours
Merit Order
#
Site
Zone
Bid £/MWh
Accepted MW
Not taken MW
vs E-Boiler
Network constraints (NESO day-ahead)
Group
Where
Flow MW
Limit MW
%
Circuit ratings crossing*
* Sum of ETYS 2025 Appendix B ratings (current BSC season: winter Dec–Feb, spring Mar–May, summer Jun–Aug, autumn Sep–Nov) of the circuits drawn crossing B4 / B5 / B6 that could be matched. Ratings are not limits: NESO's limit allows for a circuit tripping.
