NESO
National Energy System Operator
Network OperatorsThe publicly owned body that balances Great Britain's electricity system in real time and publishes the TNUoS and BSUoS tariffs. It took over from National Grid ESO on 1 October 2024.
NESO runs Great Britain's national energy system. It began on 1 October 2024, when the government bought National Grid Electricity System Operator Limited, took it into public ownership and made it independent of National Grid. It took over the ESO's electricity system operator roles, and gained gas system planning from National Gas Transmission.
While DNOs run local distribution networks, NESO operates the national transmission system. It does not own the transmission wires (the transmission owners do), but it decides how power flows across them and keeps supply and demand matched.
Key responsibilities:
- Second-by-second balancing of supply and demand from its control room
- Procuring and dispatching balancing services
- Setting and publishing TNUoS tariffs under the CUSC charging methodology
- Setting and publishing BSUoS tariffs, fixed in advance since CMP361 (April 2023)
- Acting as Delivery Body for the Capacity Market (prequalification and auctions)
- Long-term planning of the elec and gas systems
Why the name matters: Charging statements and tariff data published before October 2024 carry the National Grid ESO name; later ones come from NESO. The charges themselves did not change with the handover. Only the publisher did.
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