Calder Hall
Sellafield, Cumbria
Reactor Data
Reactor Units
Every power reactor at this site as listed in the IAEA Power Reactor Information System (PRIS): reactor type and model, net electrical capacity, grid connection and commercial operation dates, and current status.
4 units: 4 permanent shutdown.
| Unit | Type | Model | Net MWe | Construction | Grid | Commercial Op | Shutdown | Status |
|---|---|---|---|---|---|---|---|---|
| Calder Hall 1 | GCR | MAGNOX | 50 | 1953-08-01 | 1956-08-27 | 1956-10-01 | 2003-03-31 | Permanent Shutdown |
| Calder Hall 2 | GCR | MAGNOX | 50 | 1953-08-01 | 1957-02-01 | 1957-02-01 | 2003-03-31 | Permanent Shutdown |
| Calder Hall 3 | GCR | MAGNOX | 50 | 1955-08-01 | 1958-03-01 | 1958-05-01 | 2003-03-31 | Permanent Shutdown |
| Calder Hall 4 | GCR | MAGNOX | 50 | 1955-08-01 | 1959-04-01 | 1959-04-01 | 2003-03-31 | Permanent Shutdown |
Capacity, milestones and suppliers
| Unit | Design MWe | Gross MWe | Thermal MWt | First Criticality | Reactor Supplier | Turbine Supplier | Notes |
|---|---|---|---|---|---|---|---|
| Calder Hall 1 | 35 | 60 | 268 | 1956-05-01 | UNITED KINGDOM ATOMIC ENERGY AUTHORITY | C.A.PARSONS | |
| Calder Hall 2 | 35 | 60 | 268 | 1956-12-01 | UNITED KINGDOM ATOMIC ENERGY AUTHORITY | C.A.PARSONS | |
| Calder Hall 3 | 35 | 60 | 268 | 1958-01-01 | UNITED KINGDOM ATOMIC ENERGY AUTHORITY | C.A.PARSONS | |
| Calder Hall 4 | 35 | 60 | 268 | 1958-12-01 | UNITED KINGDOM ATOMIC ENERGY AUTHORITY | C.A.PARSONS |
Lifetime performance, through 2025
| Unit | Electricity Supplied | Load Factor | Energy Availability | Operating Factor |
|---|---|---|---|---|
| Calder Hall 1 | 14.0 TWh | 76.9% | 79.6% | 82.3% |
| Calder Hall 2 | 14.0 TWh | 76.9% | 79.6% | 82.7% |
| Calder Hall 3 | 14.0 TWh | 76.9% | 79.6% | 82.7% |
| Calder Hall 4 | 14.0 TWh | 76.9% | 79.6% | 82.7% |
Operator: Sellafield Limited
Owner: Nuclear Decommissioning Authority
Source: IAEA Power Reactor Information System (PRIS), as of 2026-10-26.
Working Here
Per Diem Rates FY 2026
Per diem covers lodging and meals & incidental expenses (M&IE) for government and contractor travel near this facility. Rates are from the U.S. State Department foreign per diem tables for FY 2026.
$252
Lodging/Night
$108
M&IE/Day
$360
Total/Day
United Kingdom: rate for locations the State Department does not list separately
U.S. Department of State foreign per diem, for U.S. government and contractor travel.
Photos
Photos of this facility from the NukeWorker photo gallery. Click the header or any photo to browse the full album.
Facility Map
Interactive satellite map showing the facility's geographic location. Marker color indicates current status: green for online, red for offline, orange for reduced power. Click the header to open in Google Maps satellite view.
54.4227, -3.49496
Location & Contact
Physical address, phone number, and website for this facility. Use the directions link to get driving directions via Google Maps.
Plant Facts
About This Site
Written by NukeWorker from public records: facts that do not change. Operator, status and capacity come from the live data elsewhere on this page. Sources: Wikipedia: Calder Hall nuclear power station.
Calder Hall was a nuclear power station on the Sellafield site in Cumbria, North West England. It had four graphite-moderated, carbon-dioxide-cooled Magnox reactors fueled with natural uranium.
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Construction began in 1953. The first reactor was connected to the grid in August 1956, and the station was officially opened by Queen Elizabeth II on 17 October 1956. The other three reactors were connected between 1957 and 1959. All four reactors were permanently shut down on 31 March 2003, three years earlier than planned. Its cooling towers were demolished by controlled implosion on 29 September 2007, and the reactors were fully defueled in 2019.