The Electricity System Operator (ESO) is to become the National Energy System Operator (NESO) in summer 2024, according to the Welsh Government's Heat Strategy for Wales, published in July 20241. The strategy records the change in its timeline of key policies, listing the Energy Act 2023 as passed and the ESO as due "to become National Energy System Operator (NESO) in summer 2024"1.
The same document sets out the wider policy context in which the transition sits. It states that "The Energy Act 2023 has been passed"1, the legislation under which the new body is established. The strategy does not give a precise date within summer 2024 for the change, and no further detail on the transfer of functions, staffing or licensing has been reported in the document1.
On the heat side, the strategy records several dated commitments that bear on how homes are supplied and heated. It states that "The UK Government has confirmed that the Clean Heat Market Mechanism (CHMM) will launch in April 2025"1, and that the Welsh Government will "introduce a new relief scheme for heat networks in April 2024"1. The latest iteration of the Nest scheme, it says, "launched on 1 April 2024, is explicitly focused on reducing greenhouse gas emissions from homes as well as addressing fuel poverty"1.
The strategy also notes where proposals have been dropped or deferred. It states that "Further increases (EPC C by 2025) proposed within the Minimum Energy Performance of Buildings Bill were scrapped in September 2023"1. On hydrogen, it refers to the "UK Government's decision on hydrogen in the gas network in 2026"1. On flexibility, it records that "Project Equinox, which ran its first trials in early 2023, is testing commercial models for domestic flexibility from heat pumps"1.
| Policy or measure | Date given |
|---|---|
| Energy Act 2023 | Passed |
| ESO to become NESO | Summer 2024 |
| Heat networks relief scheme (Welsh Government) | April 2024 |
| Nest scheme, latest iteration | 1 April 2024 |
| Clean Heat Market Mechanism launch | April 2025 |
| EPC C by 2025 proposals | Scrapped September 2023 |
| UK Government decision on hydrogen in the gas network | 2026 |
Why it matters for households
The body that balances supply and demand across the transmission network, and that increasingly runs the markets and services behind household electricity, changes name and legal footing in summer 20241. For a household, the practical effect is not a change to the wires or the meter but to who operates the system that keeps supply secure and that procures the flexibility services increasingly drawn from home batteries, heat pumps and electric vehicles1. The strategy frames this alongside a wider set of dates affecting how homes are heated and how their performance is rated, including the April 2025 launch of the Clean Heat Market Mechanism and the 2026 decision on hydrogen in the gas network1. It also records that proposed EPC C requirements by 2025 were scrapped in September 20231, so the timetable for minimum standards in the owner-occupied sector is not settled in this document. The strategy states that heat accounts for approximately 50 per cent of total energy use in Wales and that the most recent energy crisis is estimated to have put 45 per cent of Welsh households at risk of fuel poverty1.
What happens next
The strategy gives summer 2024 for the ESO's transition to NESO1. It gives April 2025 for the launch of the Clean Heat Market Mechanism and 2026 for the UK Government's decision on hydrogen in the gas network1. No date beyond summer 2024 for the completion of the NESO transition has been reported1.
Sources1 cited
- Heat strategy for Wales, gov.wales