MAGNOX
The MAGNOX is a Generation I gas-cooled reactor. 1 unit is operating and 0 are under construction, out of 30 on record.
Operating
1
0.0 GW gross
Under construction
0
Planned
0
Cancelled
1
28 retired
Britain's first commercial reactor line, named for the magnesium alloy cladding on its natural uranium metal fuel. Carbon dioxide cooled, graphite moderated, and dual-purpose in the early units — producing plutonium alongside electricity. Built by several UK consortia rather than a single vendor. All units are now retired; Wylfa, the last, shut in 2015.
Design
| Vendor | built by consortium, no single vendor |
|---|---|
| Reactor type | Gas-cooled reactor (GCR) |
| Generation | I |
| Capacity range | 50–590 MWe gross |
| Coolant | Carbon dioxide |
| Typical enrichment | Natural uranium to 2.5–3.5% U-235 |
Where it is built
| North Korea | 2 units, 1 operating |
|---|---|
| United Kingdom | 26 units |
| Italy | 1 unit |
| Japan | 1 unit |
All MAGNOX units
| Unit | Country | Status | Gross MW | Online |
|---|---|---|---|---|
| Nyongbyon nuclear power plant 1 | North Korea | 5 | 1985 | |
| Berkeley nuclear power plant 1 | United Kingdom | Retired | 166 | 1962 |
| Berkeley nuclear power plant 2 | United Kingdom | Retired | 166 | 1962 |
| Bradwell nuclear power plant 1 | United Kingdom | Retired | 146 | 1962 |
| Bradwell nuclear power plant 2 | United Kingdom | Retired | 146 | 1962 |
| Calder Hall nuclear power plant 1 | United Kingdom | Retired | 60 | 1956 |
| Calder Hall nuclear power plant 2 | United Kingdom | Retired | 60 | 1957 |
| Calder Hall nuclear power plant 3 | United Kingdom | Retired | 60 | 1958 |
| Calder Hall nuclear power plant 4 | United Kingdom | Retired | 60 | 1959 |
| Chapelcross nuclear power plant 1 | United Kingdom | Retired | 60 | 1959 |
| Chapelcross nuclear power plant 2 | United Kingdom | Retired | 60 | 1959 |
| Chapelcross nuclear power plant 3 | United Kingdom | Retired | 60 | 1959 |
| Chapelcross nuclear power plant 4 | United Kingdom | Retired | 60 | 1960 |
| Dungeness nuclear power plant A1 | United Kingdom | Retired | 230 | 1965 |
| Dungeness nuclear power plant A2 | United Kingdom | Retired | 230 | 1965 |
| Hinkley Point nuclear power plant A1 | United Kingdom | Retired | 267 | 1965 |
| Hinkley Point nuclear power plant A2 | United Kingdom | Retired | 267 | 1965 |
| Hunterston nuclear power plant A1 | United Kingdom | Retired | 173 | 1964 |
| Hunterston nuclear power plant A2 | United Kingdom | Retired | 173 | 1964 |
| Latina nuclear power plant | Italy | Retired | 160 | 1964 |
| Nyongbyon nuclear power plant 2 | North Korea | Cancelled | 50 | — |
| Oldbury nuclear power plant A1 | United Kingdom | Retired | 230 | 1967 |
| Oldbury nuclear power plant A2 | United Kingdom | Retired | 230 | 1968 |
| Sizewell nuclear power plant A1 | United Kingdom | Retired | 245 | 1966 |
| Sizewell nuclear power plant A2 | United Kingdom | Retired | 245 | 1966 |
| Tokai nuclear power plant 1 | Japan | Retired | 166 | 1966 |
| Trawsfynydd nuclear power plant 1 | United Kingdom | Retired | 235 | 1965 |
| Trawsfynydd nuclear power plant 2 | United Kingdom | Retired | 235 | 1965 |
| Wylfa nuclear power plant 1 | United Kingdom | Retired | 530 | 1971 |
| Wylfa nuclear power plant 2 | United Kingdom | Retired | 540 | 1972 |
Sources
- MAGNOX — vendor documentation
- Global Nuclear Power Tracker, Global Energy Monitor, August 2026 release — CC BY 4.0 · retrieved 2026-09-06