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The grid is run by three different kinds of company. The system operator directs it, the transmission owner owns the high-voltage backbone, and the distribution operators own the local cables. These guides explain each one in plain words.
The system operator
NESO explained
The National Energy System Operator: what it does, why it was created in October 2024, who owns it, and how it keeps the lights on without owning a single cable.
Read the guideWho does what
National Grid vs DNO vs NESO
The three jobs on the grid: who owns the high-voltage motorway, who owns the local roads to your home, and who directs the traffic. The clearest split you will find.
Read the guideThe transmission backbone
What is the National Grid
National Grid owns the high-voltage transmission network in England and Wales. What it is, what it owns, and what it no longer does.
Read the guideThe one thing most people get wrong
Ask who runs the National Grid and most people will say "National Grid". That was true until 2024. The job of running the grid (deciding which power stations fire up, balancing supply and demand, planning the future network) was deliberately separated from the company that owns the wires. Since 1 October 2024, that job belongs to the National Energy System Operator, a publicly owned body. The owner of the cables and the operator of the system are now two different organisations, on purpose.
Why this matters to you
When you read that "the grid is under strain" or there is a "capacity margin notice" in winter, that is the system operator (NESO) talking, not your supplier and not National Grid. NESO decides whether Britain has enough power tonight. Understanding who holds which lever is the difference between blaming the wrong company and knowing where a decision actually comes from.
The system you cannot switch, and the one you can
NESO runs the grid and National Grid owns the wires, neither is yours to choose. Your supplier is. Compare every live UK tariff, cheapest first, and switch the part that changes your bill.
Cheapest live rate now: British Gas at 23.85p/kWh, about 3% below the 24.67p cap.
System operator: your questions answered
The system operator is the body that runs Great Britain's electricity grid in real time, making sure supply and demand match every second. Since 1 October 2024 this is the National Energy System Operator (NESO), a publicly owned company. It does not own the cables and does not sell electricity: it directs the system, like air traffic control for power.
Not any more. Until 2024 the system operator was part of National Grid (as National Grid ESO). It was separated and taken into public ownership to become NESO, independent of National Grid. National Grid still owns the high-voltage transmission network in England and Wales, but it no longer runs the system.
To remove a conflict of interest. The body that decides which power projects connect to the grid and how the network should grow should not also be a private company that profits from owning that network. Making the system operator independent and publicly owned means its planning decisions are made for the whole system, not for one owner's returns.
No. NESO works behind the scenes with generators, network owners and the regulator. Households never deal with it. For a power cut you call 105 (or your local operator), and for billing you contact your supplier. The system operator has no role in your individual connection.