EDF Energy owns eight nuclear power stations in the UK (15 reactors) of which three (six reactors) have been moved to defueling operations. The total generating capacity was 7.3GW at the start of 2022 and 5.9GW at the end. Centrica plc. (Centrica) holds a 20% shareholding in Lake Acquisitions Limited, the parent company in which the nuclear generation assets sit (except Nuclear New Build).
Dungeness B was moved to defueling operations in 2021 and Hunterston B and Hinkley Point B from January 2022 and August 2022 respectively as previously planned.
Seven of the eight nuclear power stations are AGR power stations (Dungeness B, Hartlepool, Heysham 1, Heysham 2, Hinkley Point B, Hunterston B and Torness) and the eighth, Sizewell B, is a Pressurised Water Reactor (PWR) power station.
Nuclear safety is EDF Energy’s overriding priority. In 2022, 2 events on the International Nuclear Event Scale (INES scale) were recorded, both of which were rated at Level 1 (anomaly).
EDF Energy operates to strict procedures to minimise and control the radiation doses received by employees and contractors at all of EDF Energy’s existing nuclear power stations. In 2022, the average individual dose received by all workers on EDF
Energy’s existing nuclear sites was approximately 0.022mSv. The highest individual dose received in 2022 was 2.7mSv, with the legal dose limit being 20mSv per year.
The actual lifetime of each power station is determined primarily by the technical and economic practicability of supporting its safety case. This is assessed at each statutory outage for the following operating period through inspection, maintenance, testing and assessment of plant performance. Following the outage, consent is required from the Office for Nuclear regulation (ONR) before restarting the reactor. The operating period between statutory outages is normally three years for the AGR power stations and eighteen months for Sizewell B.
In addition, every ten years, the stations are subject to a more detailed and wide-ranging Periodic Safety Review (PSR) of design, operational and organisational safety which must also be accepted by the ONR in order to secure continued operation. The next PSR due for submission to ONR is in January 2024 for Sizewell B, with their decision expected in January 2025.
The AGR fleet were designed with a nominal 25-year lifetime, and Sizewell B with a 40 year lifetime. However, with the aggregation of technical information, and operational and safety experience of EDF Energy, it has been possible to extend the expected AGR lifetimes. Since British Energy was acquired by EDF, the AGR lifetimes have been extended by an average of six years.
See also in section 2.2.5 in Risk factor 5A “Nuclear facilities in the United Kingdom”.
| Power Plant | Power (1) (in MW) | Output (2) (in TWh) | |
|---|---|---|---|
| AGR Power Plants | 2022 | 2021 | |
| Dungeness B | - | - | (0.2) |
| Hartlepool | 1,185 | 7.7 | 5.7 |
| Heysham 1 | 1,060 | 6.3 | 5.8 |
| Heysham 2 | 1,240 | 7.9 | 5.8 |
| Hinkley Point B | 965 | 4.1 | 4.8 |
| Hunterston B | 495 | 0.1 | 6.4 |
| Torness | 1,200 | 7.2 | 6.7 |
| PWR Power Plant | |||
| Sizewell B | 1,198 | 10.4 | 6.7 |
| TOTAL | 7,343 | 43.6 | 41.7 |
| LOAD FACTOR (3) | 77% | 59% | |
(1) Capacities are stated for all generating reactors, net of all power consumed for the power stations’ own use including power imported from the grid, at 1 January 2022. At 31 December 2022, Hunterston B Reactor 4 and Hinkley Point B had been moved to defueling operations and the capacity of the generating reactors became 5,883MW.
(2) Output in each year reflects any refuelling, planned and unplanned outages. Imports for non-generating stations are excluded.
(3) Load factors are obtained by dividing the actual output by the output that would have been achieved by each power plant operated at its stated capacity appropriate for the period. For 2022, Hinkley Point B has been included up to 30 June i.e. the end of the last quarter before end of generation, consistent with the WANO (World Association of Nuclear Operators) treatment of operational performance indicators.
The nuclear generation fleet produced 43.6TWh during 2022, 1.9TWh more than 2021 (41.7TWh). The increase in output is largely due to:
Following suspension of On-load refuelling in 2021 on all four reactors at Heysham 2 and Torness, the decision was taken in 2022 to continue off load refuelling for the remainder of their operational lives.
