THE POWER BEHIND THE PLUG

The invisible geography of Britain's electricity system.

Electricity shapes modern Britain more than almost anything else, yet the machinery that makes and moves it is mostly out of sight: power stations on the coast, wind farms beyond the horizon, pylons crossing the hills, cables under the sea. This map pulls it into view. Power is made in one place, carried hundreds of kilometres, stepped down through substations and local networks, and used somewhere else.

1. Where it is made. DESNZ's power station list (DUKES 5.11, end May 2026) shows UK-wide installed capacity of about 33,700 MW of gas, 16,900 MW of offshore wind and 5,900 MW of nuclear at major producers, and 0 MW of coal. Of the offshore wind farms mapped, about 83% of the capacity (13,981 MW) sits in the North Sea, Moray Firth and Channel; about 2,905 MW is in the Irish Sea. Point size shows installed capacity.

2. How it travels. The 400kV and 275kV overhead lines form the national backbone. In OpenStreetMap, about 6,954 km of 400kV and 2,741 km of 275kV line is mapped across Great Britain. Amber dots mark mapped 400kV substations, where voltage is stepped up or down. Dashed outlines show the 14 regional distribution areas that carry power the last mile.

3. How it connects to Europe. DUKES lists seven interconnectors to continental Europe with 8,800 MW of capacity (IFA, IFA2, ElecLink, BritNed, Nemo Link, North Sea Link, Viking Link), plus links to Ireland and Northern Ireland. White bolt markers show the Great Britain end of each operational link. Open data for the undersea routes could not be obtained, so routes are not drawn. NeuConnect (to Germany) is under construction, with completion expected in 2028, and is not shown.

Installed capacity is not generation. Every MW figure here is what a plant could produce at most. Actual output changes hour by hour with wind, sun, demand and maintenance, and is much lower than capacity on average.

Data and method. Generation: DESNZ DUKES 2026 table 5.11 (published 30 Jul 2026, position at end May 2026); only larger sites are drawn to keep the map fast (gas 100 MW and over, onshore wind 60 MW and over, solar 40 MW and over, hydro 20 MW and over, all nuclear, biomass and offshore wind). Locations are as supplied by generators. Offshore sites and cable corridors: The Crown Estate open data (England, Wales and NI waters). Distribution areas: NESO GB DNO Licence Areas (3 May 2024). Transmission lines and substations: OpenStreetMap contributors (ODbL), pulled 12 Nov 2026. This is crowdsourced and simplified, not National Grid's asset register, and may have gaps. Northern Ireland has a separate electricity system and is not drawn.

Made for the 30 Day Map Challenge, theme POWER.