Grid capacity has become the first question asked of almost any development in Britain, and the answer is spread across a planning database, a set of distribution network operator registers, a seabed leasing body and a live API. The generation, storage and flexibility map draws them together.

Everything above 150 kW

The Renewable Energy Planning Database carries every renewable and storage project above 150 kW at every stage — operational, under construction, consented, in planning, refused and abandoned. It is joined here by DUKES 5.11, which supplies the fossil and nuclear stations a renewables-only register cannot hold.

Because status travels with each site, the map answers pipeline questions as well as present-day ones: what is consented but unbuilt in a given area is often more useful than what is running.

The wires, and who owns them

Transmission lines and substations come from OpenStreetMap; the distribution estate comes from the operators themselves, with Northern Powergrid and SSEN publishing substation registers directly. Above them sit two boundary layers that decide procedure rather than physics: grid supply point boundaries, and the DNO licence areas that determine who a connection application actually goes to.

Proximity to a line is not access to it. The junction between a site and the network is a substation with headroom, which is why the substation layers matter more than the line layers for most real questions.

Offshore, and where it lands

The offshore half is easy to miss because it is named for the seabed rather than the function: offshore wind export cables are the Crown Estate and Crown Estate Scotland route agreements that carry power from a wind farm to shore. They are the offshore half of the transmission network, and the point at which they come ashore is where onshore reinforcement gets expensive.

Alongside them sit the offshore wind leasing areas themselves, and the NSTA's offshore oil and gas infrastructure and pipelines — the existing estate any new corridor has to route around.

Live carbon intensity

One layer is not static at all. Great Britain publishes regional carbon intensity every half hour, keyed to fourteen regions, and the map renders it as a choropleth over those boundaries — how clean the power is, right now, where you are looking.

It is deliberately not stored alongside the rest. A number that is stale in thirty minutes has no business sitting in a file next to registers dated 2021, so it is fetched live and joined to the geography at the moment you ask for it.

Sources

DESNZ (Renewable Energy Planning Database, DUKES), the North Sea Transition Authority, Northern Powergrid, SSEN Distribution, The Crown Estate, Crown Estate Scotland, NESO and carbonintensity.org.uk, under the Open Government Licence and the NSTA Open User Licence.