Calder Hall Nuclear Power Station

Calder Hall Nuclear Power Station is a former Magnox nuclear power station at Sellafield in Cumbria in North West England. Calder Hall was the world's first full-scale commercial nuclear power station to enter operation, and was the sister plant to the Chapelcross plant in Scotland. Both were commissioned and originally operated by the United Kingdom Atomic Energy Authority. The primary purpose of both plants was to produce weapons-grade plutonium for the UK's nuclear weapons programme, but they also generated electrical power for the National Grid.

The site is partially demolished and is being decommissioned by Sellafield Ltd. The station's four cooling towers were demolished in 2007. The reactors were fully defueled in 2019 and fuel was taken across the Sellafield site to be reprocessed within the Magnox Reprocessing Plant.

History

Calder Hall was an early development of the existing Windscale site, and due to its size required considerable extension of the site to the south east across the River Calder. It was named after Calder Hall farm, which had farmed the land it was built on, and bridges were built over the River Calder to link to the existing site. It was divided into two operating units, Calder "A" and Calder "B", each having a turbine hall and two cooling towers shared between reactors 1–2, and reactors 3-4 respectively."Reminiscences of an atom pioneer". H.G. Davey, Works General Manager Windscale and Calder Works 1947-1958. Edited, Margaret Gowing, published Ca 1960 UKAEA, Risley, Lancs.

Construction began in 1953 and was carried out by Taylor Woodrow Construction and was completed in 1956. The primary purpose was to produce plutonium for the UK's nuclear weapons programme, for weapons including the WE.177 series. Electricity was always considered to be a by-product.

Calder Hall was officially opened on 17 October 1956 by Queen Elizabeth II. It was initially owned and operated by the Production Group of the United Kingdom Atomic Energy Authority (UKAEA) until the creation of British Nuclear Fuels Limited (BNFL) in 1971. Restructuring by the British government later resulted in a new company, Sellafield Ltd, gaining responsibility for operations of the Sellafield site.

Ownership of all of the site's assets and liabilities was transferred to the Nuclear Decommissioning Authority (NDA), a new regulatory body created by the Energy Act 2004. While operations were transferred from BNFL to Sellafield Ltd.

The station was closed on 31 March 2003, the first reactor having been in use for nearly 47 years. The cooling towers were demolished by controlled implosions on 29 September 2007, by Controlled Demolition, Inc. A period of 12 weeks was required to remove asbestos in the towers' rubble.

Features

Calder Hall nuclear power station was designed by Christopher Hinton, Baron Hinton of Bankside, upon being commissioned by Prime Minister Winston Churchill in 1952, and construction began the following year. Calder Hall initially had two cooling towers, with two further added at the opposite end of the power station in 1958 and 1959. Each were in height. The four Magnox (magnesium no oxidation) 180MWth graphite moderated, carbon dioxide cooled nuclear reactors were fuelled by natural abundance uranium enclosed in magnesium-alloy cans. The layout was largely emulated at Chapelcross in 1958, though at Calder Hall, the four units are divided by A and B each with their own turbine hall, unlike Chapelcross where all four units share a turbine hall. The Calder Hall and Chapelcross design was codenamed PIPPA (Pressurised Pile Producing Power and Plutonium) by the UKAEA to denote the plant's dual commercial and military role.

The reactors each weighed 33,000 tonnes, had four heat exchangers and 1,696 nuclear fuel channels. 8 x 3,000 rpm turbines, each long, wide and high were installed to generate the electricity. The reactors were supplied by UKAEA, the turbines by C. A. Parsons and Company, and the civil engineering contractor was Taylor Woodrow Construction.

See also

* Nuclear weapons and the United Kingdom
* Nuclear power in the United Kingdom
* Energy policy of the United Kingdom
* Energy use and conservation in the United Kingdom

References

External links

{{commons category, Calder Hall nuclear power station
Calder Hall
Nuclear Engineering International wall chart, October 1956

Former nuclear power stations in England
Decommissioned nuclear power stations
Energy infrastructure completed in 1956
Buildings and structures in Cumbria