Nuclear Development in the United Kingdom

British scientists were preeminent in the development of nuclear energy through to the early 1940s. This work was picked up again after the Second World War and while the USA was initially focused on reactors for marine propulsion, the world's first commercial-scale nuclear power reactor started up in the UK in 1956.

A fleet of 26 Magnox power reactors was built, followed later by 14 advanced gas-cooled reactors (AGRs), and finally a single PWR at Sizewell B. Plans for a new era of nuclear power are now in place and described in the main information page on Nuclear Power in the United Kingdom.

Beginning of UK civil nuclear power

Following the Second World War, nuclear research in the UK was mainly focused on defence-related applicationsa. The country's first nuclear reactors were built at the Atomic Energy Research Establishment (AERE) at Harwell in Oxfordshire, which was formed at the beginning of 1946 under the UK's Ministry of Supply. The first reactor at AERE – the 3 kWth air-cooled graphite-moderated GLEEP (Graphite Low Energy Experimental Pile) – commenced operation in August 1947. This was followed by the commissioning in 1948 of the first large reactor outside the USA, the 6 MWth British Experimental Pile '0' (BEPO). The reactor demonstrated the viability of commercial power reactors and was a forerunner of the Windscale Piles1.

During 1947, the site of the former Sellafield ordnance factory – renamed Windscaleb – was announced as a new atomic energy site, and construction activities on the two Windscale Piles commenced. Fuel for the Piles was produced at the Springfields nuclear fuel manufacturing facility in Preston, established by the Ministry of Supply in 1946. Piles No 1 and 2 were completed in 1950 and 1951, respectively.

In 1953, following the government announcement that the country would begin a civil nuclear power program, the Ministry of Supply commenced construction on the first nuclear power reactors at Calder Hall on the Windscale site. The next year, the Atomic Energy Authority Act 1954 created the United Kingdom Atomic Energy Authority (UKAEA), which took on the responsibility for the UK's nuclear energy program. As well as to provide nuclear material for the country's nuclear defence programc, the role of the UKAEA was to develop nuclear reactor technology.

The UK's civil program was also to include the construction of an experimental fast breeder reactor (FBR) and in March 1954, a former wartime airfield at Dounreay in Caithness, on the north coast of Scotland, was chosen for this purpose. The UKAEA commenced work on the Dounreay Fast Reactor (DFR) the following year (see section below on UKAEA).

Magnox reactors

One of the greatest achievement's of these early years of the UKAEA was marked in October 1956 with opening by Queen Elizabeth II of the world's first commercial nuclear power station at Calder Hall (which had been grid-connected since August). The reactor was the first of eight small prototype Magnox units to be built at Calder Hall and Chapelcross (in southwest Scotland). Although Magnox reactors were initially dual-purposed, combining power generation with plutonium production for military purposes, the latter function from 1964 was confined to other facilities at Windscale. There were previously two fuel changes per year with burn-up about 400-600 MWd/t.* They used natural uranium metal fuel, had a graphite moderator and were cooled with carbon dioxide. Magnox fuel is so called because of its magnesium alloy cladding, and the chemical reactivity of this means that the fuel cannot be stored indefinitely but must be reprocessed.

* the Calder Hall codename was PIPPA – pressurized pile producing power and plutonium.

Subsequent Magnox units were progressively scaled up tenfold and optimised for continuous electricity production. The thermal efficiency was initially very low – 22% for the first single-use ones and this rose to 28% for the later ones of the 26 built in UK. Two were sold to Japan and Italy, and similar units were built in Francee. Design life was originally 20 years, but most ran for at least twice that period.

UK Magnox reactors

Reactor MWe net Startup Status Operating life (years)
Berkeley 1 138 1962 Shutdown 1989 27
Berkeley 2 138 1962 Shutdown 1988 26
Bradwell 1 123 1962 Shutdown 2002 40
Bradwell 2 123 1962 Shutdown 2002 40
Calder Hall 1 50 1956 Shutdown 2003 47
Calder Hall 2 50 1957 Shutdown 2003 46
Calder Hall 3 50 1958 Shutdown 2003 45
Calder Hall 4 50 1959 Shutdown 2003 44
Chapelcross 1 49 1959 Shutdown 2004 45
Chapelcross 2 49 1959 Shutdown 2004 45
Chapelcross 3 49 1959 Shutdown 2004 45
Chapelcross 4 49 1960 Shutdown 2004 44
Dungeness A1 225 1965 Shutdown 2006 41
Dungeness A2 225 1965 Shutdown 2006 41
Hinkley Point A1 235 1965 Shutdown 2000 35
Hinkley Point A2 235 1965 Shutdown 2000 35
Hunterston A1 160 1964 Shutdown 1990 26
Hunterston A2 160 1964 Shutdown 1989 25
Oldbury 1 217 1967 Shutdown end Feb 2012 45
Oldbury 2 217 1968 Shutdown mid-2011 43
Sizewell A1 210 1966 Shutdown 2006 40
Sizewell A2 210 1966 Shutdown 2006 40
Trawsfynydd 1 196 1965 Shutdown 1993 28
Trawsfynydd 2 196 1965 Shutdown 1993 28
Wylfa 1 490 1971 Shutdown Dec 2015 44
Wylfa 2 490 1971 Shutdown April 2012 41
Total: 26    

In February 1955, the government published a white paper titled A programme of nuclear power announcing the first purely commercial program, building between 1400 and 1800 MWe of Magnox capacity by 1965 and investigating the future use of fast breeder reactors.

Then the 1956 Suez crisis accentuated concerns about shortages of coal and oil, prompting a white paper of April 1957, Capital investment in the coal, gas and electricity industries, which proposed increasing the nuclear build program to between 5000 and 6000 MWe.

The government gave the job of implementing the new Magnox program to the Central Electricity Authority, which was soon after replaced by the Central Electricity Generating Board (CEGB) in April 1958f. Ownership of the first eight Magnox reactors at Calder Hall and Chapelcross, as well as the country's wide range of nuclear research and development efforts – including the FBR program centred at the Dounreay site – remained with the UKAEA (see section below on UKAEA).

In 1956, construction on the twin-unit Berkeley station commenced, followed by a sister station at Bradwell the next year. Both stations started generating electricity in 1962. A further seven Magnox stations (each comprising two units) built by five different consortiaj were commissioned by 1971. Although fewer units than had been envisioned by the 1957 white paper were built – somewhat later than originally planned – as a result of the later plants being scaled up more than expected, around 4200 MWe of Magnox capacity was installed.

The advanced gas-cooled reactor

In April 1964, a government white paper, titled The Second Nuclear Power Programme, set out the next phase of the UK nuclear power program. Some 5000 MWe of capacity was expected to come online between 1970 and 1975. The Central Electricity Generating Board (CEGB) was to call for tenders for designs based on the UKAEA's advanced gas-cooled reactor (AGR) or US water-cooled reactors. Following much debate over choice of design – with the CEGB pushing for the American technology and the UKAEA favouring its own – the AGR was eventually adopted as the UK standard. In May 1965, describing the AGR as "the greatest breakthrough of all time," the Minister of Power announced that the first twin AGR station would be built at Dungeness B in Kent.

The AGR design was based on the UKAEA's 30 MWe prototype Windscale Advanced Gas-cooled Reactor (WAGR), which supplied electricity to the grid from 1963-1981. Seven twin-unit AGR stations were built, starting up 1976-89. As with the Magnox design, they are also graphite moderated and carbon dioxide cooled; but, in contrast to the Magnox reactors, the AGRs use enriched oxide fuel in a ceramic form which is burned up to low levels (relative to LWR fuel). They have a high thermal efficiency – around 40%, due to very high coolant temperatures of well over 600ºC (double the figure of many reactors). However, there was little standardization across each pair of reactorsm and operational problems were significant. The AGR is exclusive to the UK.

As was the case with the Magnox fleet, the AGRs were designed and built by private industrial nuclear power consortia as complete power stations. The Atomic Power Construction Ltd (APC)n consortium – one of three consortia competing for the contract – was awarded the first AGR contract for two 660 MWe (gross) units at Dungeness.

The other two consortia also won orders for AGR stations. In 1967, The Nuclear Power Group (TNPG)o was awarded contracts by the CEGB and the South of Scotland Electricity Board (SSEB)p for the Hinkley Point B and Hunterston B stations, respectively. Also in 1967, the Nuclear Design and Construction (NDC) consortium, which was later to become British Nuclear Design and Construction (BNDC)q, was awarded contracts from the CEGB for the Hartlepool and Heysham I stations.

Numerous problems with the original design of Dungeness B came to light during its construction, leading to several delays that were compounded by financing problems. By 1969, following the collapse of NPC, the project was taken over BNDC.

With five twin-unit AGR stations under construction, and with few more orders expected at the time, the government and the CEGB decided to merge the two remaining consortia. This led to the creation in 1973 of the National Nuclear Corporation (NNC)r from TNPG and BNDC. The Nuclear Power Company, a subsidiary of NNC, was put in charge of design and construction.

Two further AGR stations were to be ordered – Heysham II and Torness – but not until 1980, after much debate about which design of reactor was to be built next.

AGR and PWR stations

Plant name Type Present capacity (MWe net) First power Status
Dungeness B 1&2 AGR 2 x 545 1983 & 1985 Expected shutdown 2018
Hartlepool 1&2 AGR 2 x 595 1983 & 1984 Expected shutdown 2014, possibly 2019
Heysham I-1 & I-2 AGR 2 x 580 1983 & 1984 Expected shutdown 2014, possibly 2019
Heysham II-1 & II-2 AGR 2 x 615 1988 Expected shutdown 2023
Hinkley Point B 1&2 AGR 2 x 610, but operating at 70% (430 MWe) 1976 Expected shutdown 2016
Hunterston B 1&2 AGR 2 x 610, but operating at 70% (420 MWe) 1976 & 1977 Expected shutdown 2016
Torness 1&2 AGR 2 x 625 1988 & 1989 Expected shutdown 2023
Sizewell B PWR 1188 1995 Expected shutdown 2035
Total: 15 units   Approx. 8800    

The third nuclear power program 

The initial problems encountered with construction of the AGRs, particularly at Dungeness B, resulted in another debate on choice of reactor design. Several designs were considered – Magnox, AGR, HTRs, SGHWRt, Candu and PWR – with the Central Electricity Generating Board (CEGB) pushing strongly for the US-designed PWR. Following the government's choice of the SGHWR design, in February 1975, the go-ahead was given for two SGHWR plants at Sizewell B (four units) and Torness (two units) of 660 MWe capacity per reactoru.

However, due to cuts in public spending along with increasing projected costs of the SGHWR, the government put on hold financing of the initial SGHWR contracts. By mid-1977, the National Nuclear Corporation (NNC) recommended a program of new AGRs and PWRs, instead of the SGHWR. Early in 1978, the then Secretary of State for Energy Tony Benn announced that the SGHWR was to be abandoned and that the CEGB and SSEB were to each build a twin-unit AGR station. In addition, Benn said the government supported the industry's intention to order a PWR station.

In mid-1979, there was a change of government, with the Labour government of James Callaghan giving way to Margaret Thatcher's Conservatives. The new government was more supportive of the PWR and gave the go-ahead to a Westinghouse PWR at the end of 1979. It was less enthusiastic about the AGR but nevertheless confirmed in April 1980 that the two AGR stations (at Heysham and Torness) were to go ahead.

A single PWR at Sizewell B was eventually ordered, but not until a public inquiry had sat for over two years from January 1983. Government approval for the 1188 MWe four-loop Westinghouse PWR was given in 1987, and the reactor started up in 1994. The basic design was the SNUPPS (Standardised Nuclear Unit Power Plant System) with a number of modifications to meet UK requirements.

Further PWRs were planned, namely Hinkley Point C, Wylfa B and Sizewell C. A planning inquiry for Hinkley Point C was carried out in the late 1980s and consent was given in 1990. However, at the end of 1989, the government had announced that a review of nuclear policy would be carried out in 1994, until which time no new nuclear stations were to be built. Following the review, in May 1995, the government concluded that new nuclear would not receive public sector support. At the end of that year, the CEGB's successor, Nuclear Electric (see section below on Privatization), decided that further nuclear plants were not economically viable and abandoned its plans for new nuclear plants.


When the UK Atomic Energy Authority (UKAEA) was created on 19 July 1954, it inherited a number of facilities from the Ministry of Supply:

  • The Windscale site (where the two Piles had started producing plutonium for the country's weapons program and construction was underway on the Calder Hall power plant).
  • The Dounreay site in Caithness (the site chosen for the fast breeder reactor program).
  • The Atomic Energy Research Establishment (AERE) at Harwell, Oxfordshire.
  • The site of the headquarters of the Ministry of Supply's Directorate for Atomic Energy Production at Risley in Cheshirev.
  • The Atomic Weapons Research Establishment (AWRE) at Aldermaston in Berkshirew.
  • The Capenhurst gaseous diffusion plant in Cheshirex.
  • The Springfields nuclear fuel manufacturing facility in Preston, Lancashire.
  • The Radiochemical Centre at Amersham, Buckinghamshirey.

Soon after it was set up, the UKAEA acquired further sites, including Winfrith and Culham.


Early in 1957, a new site at Winfrith Heath in Dorset was chosen as a new nuclear research site – the only nuclear site to be built on a greenfield site. The site was to eventually host eight reactors, including the Dragon high temperature gas cooled reactor. Operating between 1964 and 1975, Dragon was a 20 MWth helium-cooled materials testing reactor and the first to use coated particle fuel. Another significant prototype at Winfrith was the 100 MWe (gross) steam generating heavy water reactor (SGHWR) which was a pressure-tube type with light water boiling in the core and heavy water moderation. It was the only reactor at Winfrith to generate electricity and operated from 1967 to 1990. In the early 1970s, the SGHWR was the design selected for Australiaz, as well as for the UKaa.


Fusion research was carried out at in the 1940s and '50s at AERE, where the Zero Energy Toroidal Assembly (ZETA) operated from 1954 to 1958. A new site for fusion research was identified by the UKAEA – the location of a former Royal Naval Air Station at Culham in Oxfordshire – and this was acquired in 1960. The site is now known as the Culham Science Centre.

The Culham Science Centre hosts the Culham Centre for Fusion Energy (CCFE, formerly UKAEA Culham), which includes the Joint European Torus (JET, see section on JET in the information page on Nuclear Fusion Power) and the Mega Ampere Spherical Tokamak Experiment (MAST). JET has been in operation since 1983 and in 1991 was the first facility to produce controlled fusion power. JET was originally built and operated as a Euratom project, but since the end of 1999, has been managed by the UKAEA under the European Fusion Development Agreement (EFDA). MAST began operation in 1999, following on from the Small Tight Aspect Ratio Tokamak (START) experiment (1991-1998).

Dounreay and the FBR program  

Early in 1955, construction on the 60 MWth Dounreay Fast Reactor (DFR) commencedbb. The reactor achieved criticality in November 1959 and in October 1962 became the world's first fast reactor to supply electricity to the grid. The maximum electrical power it achieved was 14.5 MW in 1963. It was cooled by liquid NaK (sodium-potassium 70:30 alloy) and shut down in 1977.

In 1958, the 25 MWth Dounreay Materials Test Reactor (DMTR) became the first operational reactor in Scotland. DMTR used enriched uranium fuel with aluminium cladding and was heavy water cooled. The reactor was shut down in 1969.

With DFR in operation, a second fast reactor at Dounreay was ordered in 1966. Construction on the Prototype Fast Reactor (PFR) commenced in 1968 and it began supplying electricity to the grid in 1975. The 660 MWth (250 MWe) reactor used plutonium metal fuel and was cooled with liquid sodium.

Despite the success of the fast reactor program, PFR was shut down in 1994 following the government's decision to withdraw its support for the program. Certain fuel cycle operations continued at Dounreay for a few years, but these ceased in 1998, since when the site has had no operational nuclear facilities.

Break-up of UKAEA

In 1971, the production activities of the UKAEA were separated out into two new companies, the main one being BNFL (see section below on BNFL). Production of medical and industrial radioisotopes at The Radiochemical Centre in Amersham, Buckinghamshire was taken over by The Radiochemical Centre Ltd, which, in 1982, became the first company to be privatized (as Amersham International) under Margaret Thatcher's Conservative government. It later changed its name to Amersham plc and, in 2004, was acquired by General Electric and incorporated into GE Healthcare.

In 1996, the commercial arm of the UKAEA was privatized as AEA Technology. However, in 2000, AEA Technology decided to sell its nuclear engineering business and also to exit the nuclear industry altogether. By March 2004, AEA Technology completed its withdrawal from the nuclear industry.

On 1 April 2005, the Nuclear Decommissioning Authority began operation, taking control of the country's nuclear liabilities, including all of the UKAEA's sites except Culham (see section on NDA below). The UKAEA's Dounreay Site Restoration Ltd (DSRL) and Research Sites Restoration Ltd (RSRL) subsidiaries responsible for remediation work at Dounreay (DSRL) and the Harwell and Winfrith (RSRL) sites were placed into a commercial business, UKAEA Ltd, in April 2008. The UKAEA agreed to sell UKAEA Ltd to Babcock International in September 20092. Following this sale, the main focus of the UKAEA is now fusion research, based at its Culham site.


In 1971, the Atomic Energy Authority Act separated two new companies out of the UKAEA, with the UKAEA retaining its research activities. Production of medical and industrial radioisotopes at The Radiochemical Centre in Amersham, Buckinghamshire was taken over by The Radiochemical Centre Ltd, and the other production activities were transferred to British Nuclear Fuels Ltd (BNFL). Responsibility for the following facilities were taken on by BNFL:

  • The Calder Hall and Chapelcross Magnox plants.
  • The Magnox reprocessing plant (often referred to as B205) on the Windscale site.
  • The Capenhurst gaseous diffusion plant.
  • The Springfields nuclear fuel manufacturing facility.
  • The Risley site, which remained BNFL's headquarters until 2003.

The Atomic Weapons Research Establishment (AWRE) was also transferred to BNFL, but soon after, in 1973, it was taken over by the Ministry of Defence.

Initially, the UKAEA held all the shares in BNFL (and The Radiochemical Centre Ltd) but in 1981, the shareholding was transferred to the Secretary of State for Energy. In 1984, BNFL became a public limited company, British Nuclear Fuels plc, still fully-owned by the government. It was to become one of the world's largest nuclear companies, providing services covering almost every part of nuclear fuel cycle.


Although much of the Windscale site was transferred to BNFL, the prototype Windscale Advanced Gas-cooled Reactor (WAGR) and the two Windscale Pilescc remained with the UKAEA. In 1981, the BNFL part of the site was renamed Sellafield, while the UKAEA's portion retained the Windscale name.

A number of major plants were built at Sellafield. Following the decision to reprocess used oxide fuel from the UK's AGR fleet, as well as from foreign nuclear reactors, the go-ahead for construction of the Thermal Oxide Reprocessing Plant (Thorp) was given in 1978. (Used Magnox fuel has been reprocessed at the B205 Magnox reprocessing plant since 1964dd.) With a design capacity of 1200 t/yr, Thorp commenced operation in 1994 (see also information page on Processing of Used Nuclear Fuel). A leak at Thorp in April 2005 put its continued operation into question, but permission to restart was given at the beginning of 2007ee. It had been planned to operate Thorp until 2011 to meet contractual commitments for AGR and overseas LWR fuel. However, following the April 2005 incident and the subsequent period of closure, Thorp has since been operating on reduced capacity due to constraints over evaporator capacity. A review of the strategy for the management of used oxide fuel resulted in a June 2012 decision to close it in 2018 after completing existing reprocessing contracts. This is conditional upon having adequate storage space for used AGR fuel and not needing to replace highly-active storage tanks (HASTs) of which there are now 21.

The MOX Demonstration Facility at Sellafield was a small-scale plant to produce commercial MOX fuel for light water reactors. The plant was commissioned between 1992 and 1994, and until 1999 produced fuel for use in Switzerland, Germany and Japanff.

In 1997, construction on the Sellafield MOX Plant (SMP) was completed but, due to a lengthy justification process, operation did not commence until 2001. The plant produced its first fuel assembly suitable for export in 2005, but was then downrated to 40 t/yr from its 120 t/yr design capacity. In August 2009, it was reported that SMP had produced only 8 tonnes of fuel (24 assemblies) in eight years, after costing £637 million to build and £626 million to operate. However, technical and commercial endeavours continued and, in May 2010, the Nuclear Decommissioning Authority (NDA, see section below on Nuclear Decommissioning Authority) announced that agreement had been reached with Japanese utilities "on an overall framework for future fabrication of MOX fuel in SMP."5

Growth and break-up of BNFL

BNFL continued to expand up to the turn of the Millennium:

  • In 1990, BNFL established a decommissioning division in the USA, known as BNFL Inc.
  • In 1998, Magnox Electric was transferred to BNFL, bringing ownership of all the UK's Magnox reactors under BNFL (see section on Privatization below).
  • In 1999, BNFL acquired Westinghouse Electric Company for $1.1 billion.
  • BNFL bought the nuclear business of ABB for $485 million in 2000 and integrated it into Westinghouse.
  • In mid-2000, BNFL acquired a stake in South Africa's Pebble Bed Modular Reactor (PBMR) venturegg.

However, after initially deciding to pursue a public private partnership arrangement for BNFLhh, government policy on nuclear changed towards focusing on cleaning up the liabilities. The 2002 white paper, Managing the Nuclear Legacy – a Strategy for Action6, proposed transferring responsibility for the country's civil nuclear assets and liabilities to a new body (which was eventually named the Nuclear Decommissioning Authority). Then, much to the industry's surprise, the government made it clear in its February 2003 energy white paper, Our energy future – creating a low carbon economy7, that it had no current plans to expand the use of nuclear power. The white paper stated that the "current economics" of nuclear power "make new nuclear build an unattractive option and there are important issues of nuclear waste to be resolved." The government therefore did not propose to support new nuclear build, although it added: "But we will keep the option open."

With the change in focus towards decommissioning, the government asked BNFL to carry out a strategic review, which was completed the end of 2003 under its new chief executive, Mike Parker. This review led to the break-up of BNFL, a process that was essentially completed by May 2009.

Following the strategic review, BNFL initially reorganized into four business units: British Nuclear Groupii; Westinghouse; Nuclear Sciences and Technology Services; and Spent Fuel Services. Assets and liabilities that were to be transferred to the Nuclear Decommissioning Authority (NDA) were held in a separate unit known as BNFL ALFA until 1 April 2005, when the NDA commenced its activities. BNFL ALFA acted as an internal customer to the other BNFL businesses during this transition period.

BNFL's businesses were eventually restructured and divested as follows:

  • On 1 April 2005, Nuclear Sciences and Technology Services was renamed Nexia Solutions, which later became the National Nuclear Laboratory (NNL). In preparation for the establishment of the NNL, the main base of Nexia Solutions was moved in April 2007 to the newly-built British Technology Centre (BTC) on the Sellafield site. NNL was launched in July 2008, and its ownership transferred to the government in April 2009.
  • In October 2006, a 49% stake of Spent Fuel Services was transferred from BNFL to the Nuclear Decommissioning Authority (NDA). Spent Fuel Services was renamed International Nuclear Services Ltd (INS) in 2007 and in April 2008 the remaining 51% interest in INS was acquired by the NDA. INS is responsible for fulfilling used fuel reprocessing and MOX fuel manufacture contracts. Transportation of the materials associated with these contracts is carried out by its Pacific Nuclear Transport Limitedjj (PNTL) subsidiary.
  • Westinghouse was sold in 2006 for $5.4 billion to Toshiba Corporation (77%), The Shaw Group (20%) and Ishikawajima-Harima Heavy Industries Co., Ltd (3%)8. The acquisition included the contract to manage and operate the Springfields fuel fabrication sitekk.
  • US decommissioning business BNFL Inc changed its name to BNG America in April 2005ll. Early in 2006, BNG America was acquired by Envirocare for $90 million to form EnergySolutionsmm.
  • British Nuclear Group Project Services was acquired by VT Groupnn early in 2008.
  • At the end of 2008, the parent body contract to own the shares in Sellafield Ltd (formerly British Nuclear Group Sellafield) was awarded to Nuclear Management Partners (NMP), a US-UK-French consortium of URSoo, Amec and Areva. The agreement was for an initial period of five years with the potential of further extension periods to a total of 17 years9. Sellafield Ltd manages and operates the reprocessing and waste storage facilities at Sellafield, the closed Calder Hall and Windscale reactors, the Capenhurst site and an engineering and design centre at Risley.
  • Reactor Sites Management Company (formerly British Nuclear Group Magnox), the parent company of Magnox Electric Ltd was sold in mid-2007 to EnergySolutions Inc. Later, in October 2008, Magnox Electric Ltd was separated into two nuclear licensed companies – Magnox North Limited (responsible for Chapelcross, Hunterston A, Oldbury, Trawsfynydd and Wylfa) and Magnox South Limited (Berkeley, Bradwell, Dungeness A, Hinkley Point A and Sizewell A).  These were then combined into Magnox Ltd in January 2011. The former Calder Hall station remained under the management of Sellafield Ltd.
  • BNFL's one-third shareholding in uranium enrichment company Urenco was transferred to the government in 2008. Earlier plans by BNFL to sell its stake in the Urenco business were blocked by Urenco's German and Dutch shareholders.

Since May 2009, BNFL has had no remaining operational businesses, and in October 2010 the government announced that it was to be formally wound up, "subject to transferring remaining assets and liabilities."


At the end of 1988, the Conservative government announced that, in preparation for privatization, the Central Electricity Generating Board (CEGB) would be broken up into two utilities – National Power and PowerGen – and transmission system operator National Grid. Ownership of CEGB's nuclear power stations in England and Wales was taken on by National Power. (The Magnox stations at Calder Hall and Chapelcross remained with BNFL.) However, due to uncertainty over decommissioning and nuclear waste disposal costs, the government then decided to delay privatization of the nuclear stations and in March 1990, the nuclear division of National Power was placed into a new company named Nuclear Electric. Meanwhile, in Scotland, the nuclear assets of the South of Scotland Electricity Board (SSEB) were placed into Scottish Nuclear in April 1990 and in the following year, the non-nuclear parts of SSEB was privatized as ScottishPower.

British Energy 

A review carried out in 1994, Review of the Future Prospects for Nuclear Power in the UK (published in May 1995), concluded that moving as much of the nuclear generating industry as possible into the private sector would bring benefits for the industry, electricity consumers and taxpayers. This led to the establishment of British Energy in 1995 to take on the more modern plants for privatization.

However, the 1994 review also took the view that public sector support for a new nuclear station was inappropriate. This led to Nuclear Electric's decision not to proceed with plans to construct Hinkley Point C (which had received planning permission in 1990) and to withdraw the planning application for Sizewell C (see section above on The third nuclear power program).

Having taken ownership of the country's seven AGR stations – Scottish Nuclear's Hunterston B and Torness plus Nuclear Electric's five AGR stations – and the Sizewell B PWR, British Energy was privatized in July 1996. Scottish Nuclear's Hunterston A Magnox station (by then shutdown) and the eight Nuclear Electric Magnox stations (two of which were shutdown) were kept in the public sector under a new company, Magnox Electric plc. In March 1998, Magnox Electric was integrated with BNFL, which already operated the Calder Hall and Chapelcross Magnox stations.

British Energy initially operated successfully and became the country's largest generator by 1998. However, this success led to high payments to shareholders rather than adequate investment in plant, leading to several unplanned outages in the future. Before significant problems began to surface, the company grew ambitiously at home and abroad:

  • In an attempt to become a vertically integrated company, British Energy acquired the electricity and gas retail distribution business Swalec (South Wales Electricity) from Hyder early in 1999pp. Within a few weeks, British Energy had changed its corporate strategy away from retail sales and sold Swalec to Scottish and Southern Energy.
  • In September 1997, British Energy and Philadelphia Electric Company Energy (Peco Energy) formed AmerGen, a 50:50 joint venture company to acquire and operate nuclear plants in the USAqq. AmerGen bought Three Mile Island 1, Clinton and Oyster Creek in 1999.
  • In 2000, British Energy bought the 1960 MWe Eggborough coal-fired plant from National Power for £650 million. The purchase was largely driven by the company's concern over the effect its lack of flexible generation would have under the New Electricity Trading Arrangements, which came into force in March 2001.
  • Bruce Power was established in April 2000 by British Energy (82.4%), Cameco Corporation (15%), the Power Workers’ Union (2%) and The Society of Energy Professionals (0.6%) to acquire Ontario Power Generation's (OPG's) Bruce A and Bruce B plants (both four-unit Candu stations) in Ontariorr. In May 2001, Bruce Power leased the Bruce stations for 17 years, with options to extend the lease for up to 25 more years.

The introduction of the New Electricity Trading Arrangements in March 2001 led to considerable overcapacity due to recent construction of much gas-fired plant. The result was that wholesale prices declined to a level that was below production cost for British Energy and, in September 2002, the company was no longer able to meet its liabilities. The government granted British Energy a credit facility to allow it to continue operation and, in October 2003, British Energy agreed a restructuring deal with the government and its creditors.

Several factors contributed to the financial collapse of British Energy:10  

  • The company was saddled with expensive reprocessing contracts with BNFL (at 0.45 p/kWh – about six times what used fuel arrangements cost in the USA)ss.
  • British Energy was liable for the climate change levy (at up to 0.15 p/kWh), despite the fact that its nuclear plants do not emit carbon dioxide.
  • Having failed in its attempts to diversify into electricity supply, the lack of vertical integration left the company exposed to wholesale power prices.
  • The Eggborough coal station had been purchased at the peak of the market and its value was written down in 2002 to £300 million. While providing the company with some flexible generating capacity, it also increased the amount of electricity that had to be sold.
  • Although the AmerGen and Bruce Power projects were very successful, the need to reinvest profits (for example in work being carried out to restart the Bruce A units) meant that these businesses were not able to provide sufficient cash in the short term.
  • The AGR fleet in the UK experienced several unplanned outages largely due to inadequate investment in the past.

As a result of the restructuring of British Energy, its stakes in AmerGen and Bruce Power were soldtt, and the reprocessing contracts with BNFL renegotiated. In exchange for 100% of the equity in the company, shareholders received 2.5% equity in the restructured company, with the remainder going to British Energy's creditors. A key part of the restructuring deal was the so-called cash sweep, where the company would contribute 65% of its free cash each year to the Nuclear Liabilities Fund (NLF), which is responsible for the future cost of decommissioning British Energy's existing fleet of nuclear power stations. In mid-2007, part of the cash sweep entitlement was converted into shares, which were sold for £2.3 billion. The NLF's remaining 36% interest was sold to EDF for £4.4 billion in January 2009.

The restructuring of British Energy was completed in January 2005. Although the company's AGRs continued to experience ageing-related issues, the wholesale price of electricity increased after restructuring, and the company was in possession of prime sites for new build. As soon as the government gave the green light to new nuclear build early in 2008, British Energy became the object of a bidding war that was eventually won by EDF. The £12.5 billion acquisition was completed in January 2009. Later in 2009, Centrica bought a 20% stake in British Energy for £2.3 billion11.

Conditions attached to the acquisition of British Energy by EDF included the disposal of the 1960 MWe Eggborough coal-fired plant and EDF's 790 MWe Sutton Bridge gas-fired station. In addition EDF was required to sell land at Wylfa, Bradwell and either Dungeness or Heysham as well as to relinquish one of the three grid connection agreements it held for Hinkley Point.

Nuclear Decommissioning Authority

At the end of 2001, the government announced that it would set up a Liabilities Management Authority to manage the public sector civil nuclear liabilities. The authority, which was later named the Nuclear Decommissioning Authority (NDA), would take over the liabilities held by the UKAEA (then estimated at £7 billion) and BNFL (£35 billion), including the operating facilities such as the Thermal Oxide Reprocessing Plant (Thorp) and the Sellafield MOX Plant (SMP).

On 1 April 2005, the NDA became the owner of the UK's legacy nuclear plant and facilities. The sites taken on by the NDA were:

  • The 11 Magnox reactor sites.
  • BNFL's fuel cycle sites: Capenhurst (the site of the gaseous diffusion enrichment plant that ceased operation in 1982); the Springfields fuel fabrication site; the Sellafield site; and the low-level radioactive waste repository (LLW Repository) at Drigg close to Sellafield.
  • The UKAEA sites at Dounreay, Harwell and Winfrithuu.

Four Magnox plants were still in operation when the NDA took ownership of the fleet. The Sizewell A and Dungeness A stations closed at the end of 2006 and Oldbury and Wylfa were due to close in December 2008 and March 2010, respectively. The NDA has since extended the operating lifetimes of Oldbury 1 to June 2011 and unit 2 to the end of 2012, and Wylfa to the end of 2012 or beyond. In certain respects Wylfa is a prototype AGR design. vv

The NDA contracts out the management and operation of its sites and most of these arrangements are described in the sections above on the UKAEA and BNFL.

The estimated cost of managing the NDA's total liabilities comes to £98.0 billion (undiscounted), of which £10.2 billion is for the NDA's share of a geological disposal facilityww. Annual spending since the NDA commenced full operation has been up to £3 billion, with over £1 billion per year of this offset by operational revenuexx. Total annual expenditure is expected to fall rapidly, reaching below £1 billion per year around 2030.

Power reactor decommissioning

The government in 1995 determined that decommissioning should be undertaken as soon as reasonably practicable, the rate of dismantling being determined by a variety of factors. Experience so far among the 30 decommissioned UK reactors (listed at end of the information page on Decommissioning Nuclear Facilities) has shown that costs are lower than originally predicted.

However, part of the long-term problem in the UK is that costs for decommissioning gas-cooled reactors are much higher per unit of capacity than for light water reactors – at least five times for Magnox. This is due to the large volume of material and the need to dispose of a lot of graphite moderator. Decommissioning waste volumes per unit capacity for Magnox are ten times those for Western light water reactors.

The Magnox reactors have undergone extensive dismantling and in 2010 the twin Berkeley reactors, which closed 21 years earlier, were the first to be put into Safestor12, pending demolition in about 65 years time. The last two Magnox power stations - the only ones with prestressed concrete pressure vessels (rather than steel) - closed in 2012 and 2015.

The Nuclear Generation Decommissioning Fund was set up in 1996 to ensure a secure source of funds for eventual decommissioning of nuclear power plants operated by British Energy (BE). BE was the only contributor to the fund, to which final payment would have been made in 2035 or whenever Sizewell B was closed down. Upon privatisation of BE (see section above on British Energy), the fund received £228 million on account of the decommissioning liabilities of BE's predecessors and in recognition of sums that the Central Electricity Generating Board and Nuclear Electric had paid the Treasury for that. In 2001, the trustees of the fund reported that its value matched its liabilities. In March 2004, the fund was £440 million and BE estimated the undiscounted cost of decommissioning its plants as £5.1 billion – most not required until many years hence.

With the restructuring of BE in 2005 the assets of the fund were passed over to the new Nuclear Liabilities Fund (see section above on British Energy). The fund is administered by the NDA and was valued at £8.4 billion as of March 2010.

The government has announced a Nuclear Liabilities Financing Assurance Board (NLFAB) to provide independent scrutiny and advice on the suitability of the decommissioning programs submitted by operators of new nuclear power stations.

Geological disposal facility

The Nuclear Industry Radioactive Waste Executive (Nirex) was established by the nuclear industry in 1982 to research options for the deep geological disposal of radioactive waste. In the late 1980s, Nirex began investigations into the suitability of sites near Dounreay and Sellafield as potential low- and intermediate-level waste repositories. In 1991, Nirex announced plans to build a rock characterisation facility (RCF) at the site near Sellafield but this was rejected by Cumbria County Council. An appeal by Nirex led to a public inquiry in 1995-96 but, shortly before a general election in March 1997, the then Secretary of State for the Environment John Gummer rejected the application.

In 2001, the the UK Government (together with the devolved administrations in Scotland, Wales and Northern Ireland) initiated the Managing Radioactive Waste Safely (MRWS) programme with a public consultation on the process13. Following the consultation, an independent body, the Committee on Radioactive Waste Management (CoRWM) was set up to recommend options to provide a long-term solution to managing higher activity radioactive wastes in the UK. The scope of investigation covered an eventual 470,000 cubic metres of mostly high- and intermediate-level wastes, and also the implications of treating plutonium and depleted uranium as wastes, as well as possibly abandoning any reprocessing of used fuel.

After three years' deliberation, CoRWM recommended deep geological disposal of high- and intermediate-level wastes long-term with early closure of the repository, with "robust interim storage" in the meantime. Repository location would be on basis of community agreement, and about one-third of the UK appears to be geologically suitable. CoRWM's final report14 in July 2006 addressed questions such as retrievability, but only in principle. CoRWM said that the government should move swiftly to implement its recommendations, though it acknowledged that actually commissioning a repository could take decades. The government accepted CoRWM's key recommendationsyy and said that a new committee with the same name would be set up to give continuing advice on implementing them15. (The new CoRWM was reconstituted in October 2007, to oversee the radioactive waste management program and to provide advice to the government on it.)

In its response to CoRWM's recommendations, the government announced that the Nuclear Decommissioning Authority (NDA, see section above on Nuclear Decommissioning Authority) would take over Nirex in line with its mandate for storage and eventual geological disposal of higher activity wasteszz. Following the integration of Nirex into the NDA, the NDA established the Radioactive Waste Management Directorate (RWMD) in April 2007 to take responsibility for the geological disposal facility program.

In June 2007, the UK Government with the Welsh and Northern Ireland devolved administrationsaaa, launched the Managing Radioactive Waste Safely: A Framework for Implementing Geological Disposal consultation, which led to a June 2008 white paper of the same name17. This set out how the Government intended to manage higher activity radioactive waste in the long-term through to geological disposal, with interim storage and ongoing research and development to support its optimised implementation. It also invited communities to express an interest in opening up (without commitment) discussions with Government on the possibility of hosting a geological disposal facility at some point in the future.

Further Information


a. The British government did not decide to develop atomic weapons until January 1947, but this aim was implicit in nuclear research up to that point. [Back]

b. When the Sellafield site in the UK's Cumbria was announced as the new atomic energy site in 1946, it was renamed Windscale. Although it at first came under the Ministry of Supply, responsibility for the UK's nuclear energy program transferred to the United Kingdom Atomic Energy Authority (UKAEA) in 1954. In 1971, British Nuclear Fuels Ltd (BNFL) was spun out of the UKAEA to oversee the production activities and later, in 1981, the BNFL portion of the Windscale site was renamed Sellafield. The UKAEA part of the site – which included the Windscale Piles and the prototype Windscale Advanced Gas-cooled Reactor (WAGR) – retained the Windscale name. [Back]

c. The UKAEA was divided into four groups: Production, Reactor, Research and Weapons. The Weapons Group remained within the UKAEA until 1973, when it was transferred to the Ministry of Defence. [Back]

d. The decision to build the particular kind of reactor at Calder Hall was taken very early in the light of their intended role for producing weapons-grade plutonium while serving as prototypes for power generation, despite frequent fuel changes (to optimize production of plutonium). Also there was no spare enrichment capacity for power generation – hence the use of unenriched uranium – and any civil program had to rely on readily available materials such as graphite for moderator, carbon dioxide for heat transfer and Magnox (magnesium non-oxidising) cladding for the natural uranium fuel. [Back]

e. North Korea's 5 MWe reactor at Yongbyon – and two unfinished larger units (at Yongbyon and Taechon) – is believed to be copied from blueprints of Calder Hall. [Back]

f. Brief history of the CEGB and privatization of its nuclear plants

The British Electricity Authority (BEA) was formed following the nationalization of the electricity supply industry under the Electricity Act 1947. Following the Electricity Reorganisation (Scotland) Act 1954, the BEA was replaced by the Central Electricity Authority (CEA) and the South of Scotland Electricity Board (SSEB)g. The CEA was dissolved by the Electricity Act 1957 and replaced by the Central Electricity Generating Board (CEGB), which commenced activities in April 1958.

Following the Electricity Act 1989, the CEGB was broken up into three companies: transmission system operator National Grid Company; and two generating companies, PowerGen and National Power, with the nuclear power stations incorporated into the latter. The government then decided to delay privatization of the nuclear stations and the nuclear division of National Power was placed into a new company named Nuclear Electric, which came into being in March 1990.

In Scotland, Scottish Nuclear was formed in April 1990 to take on the nuclear assets of SSEBh. These were: two AGR stations (Torness and Hunterston B); and the Hunterston A Magnox station, which had been shut down by SSEB at the end of December 1989 (unit 2) and March 1990 (unit 1).

The UK's nuclear power stations therefore remained in public ownership until 1996, when British Energy was privatized. At that time, Scottish Nuclear's two AGR stations and Nuclear Electric's AGRs, as well as its recently completed PWR at Sizewell, were transferred to British Energy. Nuclear Electric's Magnox stations, along with Scottish Nuclear's Hunterston A, were combined into Magnox Electric and never privatized. Magnox Electric was taken over by BNFLi at the beginning of 1998. From then, all the UK's Magnox reactors, including Calder Hall and Chapelcross, were under BNFL ownership up until April 2005, when the country's civil nuclear liabilities were transferred to the Nuclear Decommissioning Authority. The AGR stations and PWR remained in British Energy, which was acquired by France's EDF in February 2009. [Back]

g. The electricity assets in the northern part of Scotland had been taken over by the North of Scotland Hydro-Electric Board when the UK electricity supply industry was nationalized in 1948. The assets of North of Scotland Hydro-Electric Board were later acquired by Scottish Hydro Electric ahead of privatization in June 1991. In December 1998, Scottish Hydro Electric merged with Southern Electric to become Scottish and Southern Energy. [Back]

h. In 1990, the nuclear assets of South of Scotland Electricity Board (SSEB) were placed into Scottish Nuclear and the non-nuclear into ScottishPower, which was to be privatized the following year. ScottishPower was acquired by Spanish energy firm Iberdrola in 2007. [Back]

i. In 1971, UKAEA was broken up into research and production divisions, with the main production division becoming British Nuclear Fuels Limited (BNFL). In 1984, BNFL became a government-owned public limited company, British Nuclear Fuels plc. [Back]

j. Four consortia were set up in 1955, and a fifth one in 1956. The first four Magnox reactor contracts were awarded in 1956-57 to: a consortium led by Associated Electrical Industries (AEI) with John Thompson, for the contract for Berkeley; Nuclear Power Plant Company (NPPC), a consortium led by C. A. Parsons, for the Bradwell contractk; a consortium led by General Electric Company (GEC – not related to the US company General Electric) with Simon Carves, for the Hunterston contractl; a consortium led by English Electric, the Hinkley Point contract. In 1959, the fifth consortium, Atomic Power Constructions (APC), led by International Combustion and Fairey Engineering, was awarded the contract for Trawsfynydd.

The contracts for the three other UK Magnox power stations were awarded to: the English Electric consortium for Sizewell A and Wylfa, in 1960 and 1963, respectively; and to TNPG (see below) for Oldbury in 1962.

In 1960, the AEI-John Thompson Nuclear Energy Company and NPPC formed The Nuclear Power Group (TNPG).

In 1962, the GEC consortium and APC formed United Power Company (UPC), though the original GEC-Simon Carves team were not included. However, UPC was dissolved in 1964. (Responsibility for the construction of Hunterston transferred to UPC during 1962-64, and then reverted to GEC.)

In 1965, the English Electric-led consortium became Nuclear Design and Construction (NDC) following its reorganization into a joint subsidiary of English Electric, Babcock & Wilcox Ltd and Taylor Woodrow Construction Ltd. With GEC's acquisition of English Electric in 1968, the NDC became British Nuclear Design and Construction (BNDC). Prior to GEC's acquisition of English Electric, in 1967, GEC had acquired Associated Electrical Industries (AEI).

As a result of these changes, the consortia that were contracted to build many of the Magnox stations had changed by the time the projects were completed. [Back]

k. NPPC also built the Latina Magnox reactor in Italy. [Back]

l. The GEC-Simon Carves Atomic Energy Division also built the Tokai Mura Magnox reactor in Japan. (As for Hunterston, the project was managed by UPC during 1962-64 – see Note j.) [Back]

m. Hinkley Point B and Hunterston B were sister stations, as were Hartlepool and Heysham I. All other nuclear plants in the UK are essentially of unique design. [Back]

n. While bidding was underway for the country's new generation of nuclear plants, General Electric Company (GEC, not related to the US company General Electric) withdrew from the United Power Company (UPC) consortium, leaving Atomic Power Constructions (APC, see Note j above), which in 1965 was awarded the contract for the first of the country's AGR stations, at Dungeness B. In 1969, the escalating costs of the project caused APC to go into administration. Meanwhile, former UPC partner GEC had merged with the English Electric-led consortium Nuclear Design and Construction (NDC) to form British Nuclear Design and Construction (BNDC). Following the collapse of APC, the Dungeness B project was taken over by a team drawn from BNDC, GEC and the Central Electricity Generating Board (CEGB, see Note f above). [Back]

o. The Nuclear Power Group (TNPG) was formed in 1960 out of two of the original five nuclear vendor consortia (see Note j above). [Back]

p. The South of Scotland Electricity Board (SSEB) and the Central Electricity Authority (CEA) replaced the British Electricity Authority (BEA) in 1954 (see Note f above). The CEA was then replaced by the Central Electricity Generating Board (CEGB) in 1958. The electricity assets in the northern part of Scotland (which did not include nuclear stations) were managed by the North of Scotland Hydro-Electric Board (see Note g above). [Back]

q. In 1965, one of the original five nuclear vendor consortia (see Note j above) reorganized into Nuclear Design and Construction (NDC), a joint subsidiary of English Electric, Babcock & Wilcox Ltd and Taylor Woodrow Construction Ltd. Following GEC's acquisition of English Electric in 1968, the NDC became British Nuclear Design and Construction (BNDC). One year earlier, in 1967, GEC had acquired Associated Electrical Industries (AEI), which had led the consortium that won the first commercial Magnox station contract (Berkeley) and, in 1960, merged with the Nuclear Power Plant Company (NPPC) company to form The Nuclear Power Group (TNPG). [Back]

r. The ownership of the National Nuclear Corporation (NNC) was divided between the UKAEA (15%), seven companies left from the old consortia (35%) plus GEC (50%). [Back]

s. A prototype high-temperature gas-cooled reactor (HTR), the 20 MWth Dragon, had been in operation at the UKAEA's Winfrith site since 1965. [Back]

t. A 100 MWe prototype of the steam-generating heavy water reactor (SGHWR) started up at UKAEA's Winfrith site in 1968. The design was favoured by the South of Scotland Electricity Board (SSEB). [Back]

u. Many political factors were at play at the time, not least the growing concerns over oil supplies prompted by the October 1973 Yom Kippur War. On the domestic front, the coal miners' strikes of 1972 and 1974 resulted in not only power cuts and a three-day working week, but also the defeat of the Conservative government (under Prime Minister Edward Heath) by Harold Wilson's Labour government. Along with the Conservatives went the main support for the Westinghouse PWR design, while the Labour government was more in favour of the indigenous SGHWR. Generally speaking, with the new Secretary of State for Energy, Eric Varley, coming from a background in the coal mining industry, prospects for the nuclear industry were less bright under the new Labour government. [Back]

v. In 1946, the Directorate of Atomic Energy Production established a research centre on a former Royal Ordnance Factory site at Risley in Cheshire to lead the country's efforts to produce an atomic bomb. The facility, which was responsible for most of the nuclear infrastructure in the UK, was taken over by the UKAEA in 1954. [Back]

w. The Atomic Weapons Research Establishment (AWRE) was established by the Ministry of Supply in April 1950 at RAF Aldermaston, a former World War II airfield in Berkshire. It was transferred to the UKAEA in 1954 and then British Nuclear Fuels Ltd (BNFL) when BNFL was created out of the UKAEA in 1971. It was taken over by the Ministry of Defence in 1973 and, in 1987, was combined with other sites to form the Atomic Weapons Establishment (AWE). [Back]

x. In 1950, the Ministry of Supply took over the site of the Capenhurst Royal Ordinance Factory and surrounding land in Cheshire to build a gaseous diffusion uranium enrichment plant. Enrichment commenced in 1952 and, from 1962 until its closure in 1982, the diffusion plant operated only as a civil facility. The site was transferred to the UKAEA in 1954 and then to British Nuclear Fuels Ltd (BNFL), when BNFL was created out of the UKAEA in 1971.

The March 1970 signing of the Treaty of Almelo between the British, Dutch and German governments led to the construction of a gaseous centrifuge enrichment plant on the Capenhurst site. Urenco was established in 1971 to market the enriched uranium product and during 1993-94 the centrifuge enrichment plant and associated facilities were transferred from BNFL to Urenco, with BNFL retaining the closed diffusion plant. [Back]

y. A national centre for the development and manufacture of radioactive materials for peacetime uses in medicine, scientific research and industry was established at Amersham, in Buckinghamshire, in 1946. It was renamed The Radiochemical Centre in 1949, and from 1950, was run as an out-station of the Atomic Energy Research Establishment at Harwell, transferring to the UKAEA in 1954.

In 1971, while the UKAEA retained its research activities, two new companies were carved out of the UKAEA: British Nuclear Fuels Ltd (BNFL) took on the production activities; and The Radiochemical Centre Ltd took over production of medical and industrial radioisotopes. In 1982, The Radiochemical Centre Ltd was privatized and renamed Amersham International plc. In 1997, the company merged with the businesses of Pharmacia Biotech (Sweden) and Nycomed (Norway) and, in 2001, changed its name to Amersham plc. In 2004, Amersham was acquired by General Electric and incorporated into GE Healthcare. [Back]

z. In 1969, plans for a nuclear power reactor at Jervis Bay, New South Wales, were approved. Following the submission of tenders in 1970, the SGHWR design was chosen. The project was cancelled in June 1971, soon after John Gorton was replaced as prime minister by William McMahon (who was against the planned nuclear power program). [Back]

aa. Following the government's choice of the SGHWR design, in February 1975 the go-ahead was given for two SGHWR plants at Sizewell B (four units) and Torness (two units) of 660 MWe capacity per reactor. However, in 1978, development of the SGHWR was abandoned in favour of the AGR (see section above on The third nuclear power program). [Back]

bb. The production of plutonium for military purposes was the main driving force behind FBR development. As was the case with the Magnox reactors that were under construction at Calder Hall at that time, power generation of the Dounreay Fast Reactor was a secondary consideration. [Back]

cc. The Windscale Piles were shut down after a severe fire occurred in Pile 1 in October 1957. [Back]

dd. The 1500 t/yr Magnox reprocessing plant at Sellafield started up in 1964, receiving used fuel from all Magnox plants. (Magnox fuel, due to the chemical reactivity of the cladding, cannot be stored indefinitely and therefore needs to be reprocessed.) In 2001, BNFL had committed to cease Magnox reprocessing by 2012. This timetable ensured all associated discharges would have ceased well before 2020, in line with the objective of the Convention for the Protection of the Marine Environment of the North-East Atlantic (the OSPAR Convention) to achieve near zero additional radionuclide concentrations in the North East Atlantic, North Sea and the Irish Sea marine environment by 2020. The main concern was the discharge of technetium-99, which was present in the waste stream from Magnox reprocessing. In 2003, the introduction of a new effluent treatment process substantially reduced the amount of Tc-99 in the waste stream, allowing Magnox reprocessing to continue well beyond 2012. The effluent discharge process uses tetraphenylphosphonium bromide to complex the Tc-99, forming a solid that can be removed from the discharge stream.

Along with BNFL's other facilities, the B205 reprocessing plant was transferred to the Nuclear Decommissioning Authority (NDA) on 1 April 2005. The planned closure date for the reprocessing plant envisaged in the NDA's Magnox Operating Programme is around 2016. [Back]

ee. A leak resulting from a pipe failure was discovered in April 2005 at Thorp. The pipe supplied dissolved used fuel in nitric acid to an accountancy tank in the plant's feed clarification cell. The 83,000 litre spill was contained in the cell but the incident was rated Level 3 on the International Nuclear Event Scale – a serious incident without off-site radiological consequences. The spilled liquid was recovered in June, and BNFL subsidiary British Nuclear Group was fined £500,000 in October 2006. The Chief Inspector of nuclear installations acknowledged that while there had been no harm to workers or the public, it nevertheless represented a major operational lapse which would not be tolerated3. [Back]

ff. In September 1999, it was discovered that some quality assurance data of fuel pellets manufactured at the MOX Demonstration Facility (MDF) had been falsified. A Nuclear Installations Inspectorate (NII) investigation into the matter stated: "The events at MDF which have been revealed in the course of this investigation could not have occurred had there been a proper safety culture within this plant."4 Eight assemblies delivered to Japan in the summer of 1999 were returned and BNFL paid £40 million compensation to Kansai Electric Power Company. The incident also resulted in the resignation of BNFL chief executive John Taylor.

MDF was closed in 1999 when the matter came to light. In 2002, BNFL was given permission to operate the plant as a support facility for the Sellafield MOX Plant, which was undergoing commissioning at the time, and some material processing was later carried out at MDF. [Back]

gg. BNFL initially acquired a 22.5% interest in the PBMR project. This was later reduced to 15%, before being transferred to BNFL's Westinghouse business, which was sold to Toshiba in 2006 (see section on PBMR in the information page on Nuclear Power in South Africa). [Back]

hh. In mid-1999, the government decided to work towards introducing a public private partnership (PPP) into BNFL, where the government would retain a 51% stake in the company. This policy changed with the 2002 white paper Managing the Nuclear Legacy – a Strategy for Action. [Back]

ii. British Nuclear Group comprised three main divisions: Nuclear Decommissioning & Cleanup, later Project Services Ltd; Spent Fuel & Engineering, later Sellafield Ltd; and Magnox Generation. [Back]

jj. Pacific Nuclear Transport Limited is owned by International Nuclear Services (62.5%); Areva subsidiary TN International (12.5%); and the Overseas Reprocessing Committee (25%), an organization belonging to the Federation of Electric Power Companies, which manages the reprocessing and transport contracts on behalf of the 10 Japanese utilities that operate nuclear power plants. [Back]

kk. When the Nuclear Decommissioning Authority (NDA) took ownership of the Springfields site on 1 April 2005, BNFL subsidiary Westinghouse continued with the management and operation (M&O) of the site through its Uranium Asset Management Ltd (UAM) business. This arrangement continued with the sale of Westinghouse to Toshiba. The M&O contract expired at the end of March 2010 and, from April 2010, Westinghouse leased the site on a long-term basis from the NDA. Responsibility for the commercial fuel manufacturing business and the workforce was transferred to Westinghouse. At the same time, UAM was replaced by a 60:40 Toshiba-Westinghouse joint venture, Advance Uranium Asset Management Ltd. [Back]

ll. The change of name from BNFL Inc to BNG America, and its incorporation into the British Nuclear Group division, coincided with the decision to adopt a low-risk strategy. BNFL Inc had previously got into financial difficulty over two major fixed-price contracts with the US Department of Energy – the East Tennessee Technology Park (ETTP) project at Oak Ridge and the Advanced Mixed Waste Treatment Plant (AMWTP) at Idaho. Due to the high level of financial uncertainty associated with them, these contracts had to be resolved before there could be any clarity on the future of the decommissioning division. Agreement between the UK and US governments regarding the closure of these contracts was reached early in 2005. [Back]

mm. EnergySolutions was initially formed from the merger of Envirocare of Utah, Scientech D&D and BNG America. Envirocare bought Scientech D&D in October 2005. Early in February 2006, Envirocare's $90 million acquisition of BNG America was announced, with the three merged companies forming EnergySolutions. Also in early February 2006, EnergySolutions announced the acquisition of Duratek. [Back]

nn. Defence and support services company VT Group completed the acquisition of British Nuclear Group Project Services Limited – to form VT Nuclear Services – in January 2008. In July 2010, VT Group was acquired by Babcock International Group. [Back]

oo. The Nuclear Management Partners consortium was formed by Washington Group International, Amec and Areva to bid for the parent body contract of Sellafield Ltd, the competition for which was launched in November 2006. The US partner became the Washington Division of URS, following the acquisition of Washington Group International by URS in November 2007. [Back]

pp. One of 15 area electricity boards formed under the Electricity Act 1947, South Wales Electricity Board was bought out in 1996 by Welsh Water, which was rebranded as Hyder. The Swalec (South Wales Electricity) brand was maintained within Hyder and Swalec Gas was established when deregulation of the gas market commenced in 1997. The Swalec electricity and gas supply business, along with the Swalec brand, was sold to British Energy in June 2000 for £105 million. In August of the same year, unable to acquire further electricity supply companies, British Energy instead sold its Swalec business to Scottish and Southern Energy (SSE, see Note g above) for £210 million. [Back]

qq. Philadelphia Electric Company Energy merged with Commonwealth Edison owner Unicom in October 2000 to form Exelon Corporation. In 2003, Exelon acquired British Energy's 50% stake in AmerGen and incorporated it into its Exelon Nuclear business unit. [Back]

rr. The four Bruce A units had been laid-up at the time they were leased by Ontario Power Generation to Bruce Power (see information page on Nuclear Power in Canada, in particular the section on Reactor refurbishment: Bruce). [Back]

ss. Soon after privatization, British Energy had renegotiated its reprocessing contracts with BNFL. The pricing of the contracts – amounting to some £400 million per year – was linked to inflation at BNFL's insistence, whereas British Energy had wanted it to be linked to electricity prices. When wholesale electricity prices (and consequently British Energy's revenues) fell, British Energy faced rising reprocessing costs. [Back]

tt. British Energy's 50% stake (approximately 1250 MWe) in AmerGen was purchased by Exelon for $276.5 million.
79.8% of British Energy's 82.4% stake in Bruce Power (along with British Energy's 50% interest in Huron Wind, which owns five 1.8 MWe wind turbines next to the Bruce Power Visitors Centre) went to a consortium made up of Cameco, BPC Generation Infrastructure Trust and TransCanada PipeLines Limited. The remaining 2.6% went to the Power Workers' Union and The Society of Energy Professionals. The sale was expected to raise C$ 770 million, but C$ 630 million (around £250 million) was paid on closing the deal, with the rest dependent on a number of contingencies, in particular that Bruce A1 and A2 would be restarted by 15 June 2003 and 1 August 2003, respectively. As a result of the disposal, Bruce Power was owned by: Cameco (31.6%); BPC Generation Infrastructure Trust (31.6%); TransCanada PipeLines Limited (31.6%); the Power Workers' Union (4%); and The Society of Energy Professionals (1.2%). [Back]

uu. The Culham site was not transferred to the Nuclear Decommissioning Authority and ownership of the site remained with the UKAEA. Although no decision has been made, it is likely that the government will transfer the management of the nuclear liabilities at Culham to the Nuclear Decommissioning Authority when facilities such as the Joint European Torus (JET) facility enter the decommissioning phase. [Back]

vv. Operation of Oldbury 1 is currently expected to cease by the end of 2012, or when the fuel runs out. [Back]

ww. The estimated costs for decommissioning and clean-up of the UK's civil nuclear liabilities have generally been increasing. The 2002 white paper Managing the Nuclear Legacy – A strategy for action (see Reference 6) estimated these costs at £48 billion. By the time of the Nuclear Decommissioning Authority's (NDA's) 2010/11 annual report, the estimated costs of the NDA's nuclear liabilities were £98.0 billion (undiscounted) including the NDA's share of the planned geological disposal facility (£10.2 billion out of the full estimated cost of £11.5 billion). [Back]

xx. The Nuclear Decommissioning Authority's operational income reached nearly £2 billion in the financial year to end March 2009. However, income for the year to March 2010 had fallen to £1,266 million, and to £1,096 million in the year to March 2011. Operational expenditure in the year to March 2011 was £2.8 billion (£2.6 billion in the year to March 2010) before adjustments. [Back]

yy. It is worth noting that one of the main points made by CoRWM in its Managing our Radioactive Waste Safely report (see Reference 14) was apparently sidestepped by the Government. CoRWM's report stated: "It must be emphasised that CoRWM’s recommendations are directed to existing and committed waste arisings." However, in its response (see Reference 15) to CoRWM's recommendations, the Government said that negotiations with potential host communities would "take into account not only wastes that will arise from sites owned by the Nuclear Decommissioning Authority but also wastes that have arisen, or will arise, from other organisations’ UK nuclear activities."

As CoRWM pointed out in its report, the Government published its July 2006 energy policy review – which effectively reversed the Government's opposition to new nuclear build – when CoRWM was in the process of finalizing its recommendations. CoRWM's recommendations, therefore, applied to what it referred to as the 'CoRWM inventory', and not to wastes from new build. According to CoRWM: "Should a new build programme be introduced, in CoRWM’s view it would require a quite separate process to test and validate proposals for the management of the wastes arising." [Back]

zz. In April 2005, the government assumed control of Nirex and gave it independence from the nuclear industry in order to achieve greater transparency for its endeavours. Up to that point, shares in Nirex were held by BNFL, UKAEA and British Energy. The Ministry of Defence provided funds but was not a shareholder. [Back]

aaa. The Scottish devolved administration pulled out of the Managing Radioactive Waste Safely program due to its opposition to final disposal of nuclear waste in a geological disposal facility16. Announcing the decision, Cabinet Secretary for Rural Affairs and the Environment Richard Lochhead said: "This out of sight out of mind policy should not extend to Scotland." [Back]


1. Harwell project profiles: BEPO – British Experimental Pile O, UKAEA; David Fishlock, Curtains for BEPO, Nuclear Engineering International (February 2009) [Back]

2. Babcock International Group PLC Acquisition of UKAEA Limited Class 3 Transaction, Babcock International Group (18 September 2009) [Back]

3. Culture clubbed, Nuclear Engineering International (April 2007) [Back]

4. An Investigation into the Falsification of Pellet Diameter Data in the MOX Demonstration Facility at the BNFL Sellafield Site and the Effect of this on the Safety of MOX Fuel in Use, UK Health and Safety Executive (February 2000) [Back]

5. The Future of the Sellafield MOX Plant (SMP) May 2010, Nuclear Decommissioning Authority news release (12 May 2010) [Back]

6. Managing the Nuclear Legacy – A strategy for action, Department for Trade and Industry (July 2002) [Back]

7. Energy white paper, Our energy future – creating a low carbon economy, Cm 5761, Department for Trade and Industry (February 2003) [Back]

8. Toshiba Completes Westinghouse Acquisition, Toshiba Corporation press release (17 October 2006) [Back]

9. NDA secures new delivery partner for £22 billion Sellafield Ltd contract, Nuclear Decommissioning Authority news release (24 November 2008) [Back]

10. Risk Management: The Nuclear Liabilities of British Energy plc, National Audit Office, 6 February 2004 (ISBN: 0102927138) [Back]

11. Centrica to invest in EDF nuclear business in the UK; EDF to acquire controlling stake in SPE from Centrica, Centrica news release (11 May 2009). The same news release was also published by EDF on the same date. [Back]

12. Reactor closure marks a first for the UK nuclear sector, Nuclear Decommissioning Authority news release (15 December 2010) [Back]

13. Managing Radioactive Waste Safely: Proposals for developing a policy for managing solid radioactive waste in the UK, Department for Environment, Food and Rural Affairs; Department of the Environment; National Assembly for Wales; and Scottish Executive (September 2001) [Back]

14. Managing our Radioactive Waste Safely: CoRWM’s recommendations to Government, Committee on Radioactive Waste Management (July 2006). The document is also available in Word format. [Back]

15. Response to the Report and Recommendations from the Committee on Radioactive Waste Management (CoRWM), UK Government and the devolved administrations (October 2006) [Back]

16. Ministers decline to endorse deep storage, Scottish Government news release (25 June 2007) [Back]

17. Managing Radioactive Waste Safely: A Framework for Implementing Geological Disposal, Department for Environment, Food and Rural Affairs, Cm 7386 (June 2008) [Back]

General sources

United Kingdom (part1), Nuclear Engineering International (March 1998)

Andy Munn, UKAEA's first 50 years, Nuclear Engineering International (November 2004)

Rob Cochrane, The CEGB Story, Portsmouth Publishing and Printing Ltd (March 1990)

S. H. Wearne and R. H. Bird, UK Experience of Consortia Engineering for Nuclear Power Stations, School of Mechanical, Aerospace & Civil Engineering, University of Manchester (2009, updated February 2010)

Simon Taylor, Privatisation and Financial Collapse in the Nuclear Industry: The Origins and Causes of the British Energy Crisis of 2002, Routledge, July 2007 (ISBN: 9780415431750)

Ian Jackson, Utilities signal preferred UK sites, Nuclear Engineering International (April 2009)

Nuclear Decommissioning Authority website (

Nuclear Liabilities Fund website (

Magnox Ltd website (

United Kingdom