Electricity transmission network requirements
Great Britain’s NETS must continue to adapt and be developed so power can be transported from source to demand, reliably and efficiently.
East of England boundaries
The East of England region includes the counties of Norfolk and Suffolk, with EC5 being the only boundary within this region.
North Wales and the Midlands boundaries
The Western transmission region includes boundaries in the Midlands and the north of Wales.
North of England boundaries
The North of England transmission region includes the network between the Scottish border and the North Midlands.
Boundaries B7a and B8 are in this region.
Scottish boundaries
The onshore transmission network in Scotland is owned by SSEN Transmission and SP Transmission.
The Scottish NETS is divided into seven boundaries:
South Wales and South England boundaries
The region includes the high demand area of London, generation around the Thames estuary and the long set of circuits that run around the south coast and South Wales.
Boundary charts source data
Download the source data from all of our published ETYS 2025 boundary charts in a tabulated format.