United Kingdom

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Electricity generation in the UK

Energy mix

In favour for new nuclear build

"Until recently, the UK was largely self-reliant for energy, producing significant quantities of oil, gas and coal. The gradual depletion of oil and gas reserves and a decrease in domestic coal production has led to a growing dependence on imports. In the electricity sector, gas has replaced coal as the principal fuel. Since 2005, rapidly increasing energy prices, growing concerns on security of supply and awareness of climate change have raised the profile of energy in the UK. The Government has come out strongly in favour of new nuclear build, while some regions are putting particular focus on renewable energies (particularly wind and tidal).

Electricity generation has been increasing steadily over the past 10 years. Environmental pressures and increased availability of natural gas has led to an increasing share of natural gas in the electricity fuel mix. Gas accounts for around 40% of total gross generation, with coal following with a 33% share. The share of nuclear has not experienced great fluctuations in the recent past and, in 2004, accounted for 20% of total generation." Nuclear power generation in the UK comes up to about 29% of total electricity production."
(source: EC Energy mix factsheet, data 2004)

Reactors in the UK

First reactors - Magnox

The UK's first nuclear installations, opened between 1956 and 1971, were carbon dioxide gas cooled Magnox reactors. These reactors use natural Uranium as fuel, contained in a Magnesium alloy can. The first nine installations used steel reactor pressure vessels. The last two stations at Oldbury and Wylfa use prestressed concrete reactor pressure vessels.

An issue of major safety significance for the Magnox reactors arose towards the end of the 1960s when it was discovered that certain generally low silicon steels were showing signs of breakaway and rapid oxidation. These steels had been used in fixings such as nuts, bolts and washers and, because the oxide was of greater volume than the original steel, large additional strains were induced in such components, particularly in the bolts. They often failed at unusually low strains (of less than 2%). These effects led to a major investigation, analysis and inspection of the operating Magnox reactors. As a result two actions were taken. Firstly, reactor gas outlet temperatures were reduced to below 370 °C (the oxidation effect was temperature dependent). Secondly, an annual inspection and assessment on all stations was instigated. These annual reappraisals and the more moderate temperature conditions enabled oxidation to be properly controlled. Since these steps were taken this oxidation mechanism has not been a significant safety issue.

Advanced Gas-Cooled Reactors

A major change in the design of the gas cooled reactors came with the development of AGRs. This type of reactor was opened between 1976 and 1988. They use enriched Uranium Oxide fuel clad in stainless steel. Both AGRs and Magnox use carbon dioxide as the reactor coolant. All the AGRs have prestressed concrete reactor pressure vessels.

Magnesium alloys can oxidise in air. AGRs using enriched Uranium Oxide in stainless steel cans overcame this disadvantage and also allowed considerably higher gas temperatures at the reactor outlet (over 600 °C). This, together with the development of the concrete pressure vessel allowing gas pressures of over 30 Bar, gave an important improvement in overall efficiency and fuel utilisation.

Gas-Cooled reactor containment

The UK's gas cooled reactors are designed such that they do not need a secondary containment building. This is because, under design basis loss of coolant accidents, the reactor transient does not precipitate large scale fuel failure. The plant is designed to be capable of retaining the bulk of the radioactive material that might be released from the fuel for the entire range of accidents considered in the design. In contrast, containment buildings are required for Pressurised Water Reactors and Boiling Water Reactors because a design basis loss of coolant accident results in significant fuel failure and release of radioactive fission products.

Pressurised Water Reactor

The newest nuclear installation to operate in the UK is Sizewell B. It became operational in 1995. It has a single pressurised water reactor developed from an established reactor plant design from the USA. This is the first pressurised water reactor constructed in the UK for commercial power generation.

Waste management

Spent Magnox and AGR fuel is stored at the nuclear installations for a period to allow it to cool to meet limits and conditions of irradiated fuel transport packages. There is no treatment of the fissile material before transport, but the fuel assembly is mechanically modified to minimise its volume. This modification produces low and intermediate level radioactive waste, which is stored on site in facilities designed for this purpose and from which the waste will be recovered subsequent to the operational phase. Spent PWR fuel is stored in a purpose designed pond at the nuclear installation in the form discharged from the reactor.

Developments in the nuclear sector

2010 December: UK is consulting possibility of carbon floor price for nuclear

"Some £110 billion ($170 billion) in new power plants is required in the UK to replace ageing and outdated power plants by 2020 - ahead of a possible doubling of electricity demand by 2050. [...]
The UK government is therefore consulting on a new market based on "four interlocking policy instruments," which should provide "greater assurance of decarbonisation at the same time as lower bills in the long run."

The plans include support to maintain a minimum price for carbon dioxide emissions. Scenarios for the short term are based on £20, £30 and £40 ($31, $46 and $62) per tonne, but the real figure would be set in 2011 as part of the country's budget. In the longer term all the scenarios see prices rise to £70 ($109) per tonne by 2030.

Long term feed-in tariffs would provide certainty of income for companies building low-carbon power plants. Under a 'contract for difference' arrangement the government could top up revenues if the wholesale power price dips below the tariff level. It would also have a right to 'claw back' the money if prices are high."
(source: http://www.world-nuclear-news.org)

The carbon floor price strategy is critisized to be an indirect subsidy for nuclear power and would enhance chances to find investors for nuclear construction considerably.

2009-10-28: Huge new NPP in Sellafield planned

"New reactors look likely near Sellafield after a large potential site for a power plant was purchased by Iberdrola, GdF-Suez and Scottish & Southern. Up to 3.6 GWe of nuclear capacity is planned.
The trio has secured a 190 hectare plot of land to the north of the UK's main fuel-cycle centre, Sellafield, for £70 million ($114 million) according to the Nuclear Decommissioning Authority (NDA), which sold the land.

The sale came after an offer of a 250 hectare zone earmarked for divestment in the rapidly-developing UK new build market. NDA spokesman Bill Hamilton told World Nuclear News that the consortium would have the opportunity to "cherry pick" precisely the site it wants from the 190 hectares and return the remainder to the NDA. Anything returned could be combined with the unsold 60 hectares for a new sale in future: "This is not the end of the story for new nuclear at Sellafield."

(source: world-nuclear-news.org)

2009-07-28: Regulators ask vendors to proove safety of EPR and AP1000

"The process to qualify reactor designs is progressing in the UK. As part of this process, regulators there and in Finland have raised questions about EPR's instrumentation and control.

Information from both countries' nuclear safety regulators has shed light on the tough task reactor vendors face in proving the safety of new designs ahead of use.
The UK Health and Safety Executive (HSE) said it was making "good progress" in assessing Areva's EPR and Westinghouse's AP1000 and it remains confident of signing off the Generic Design Assessment (GDA) process on time in June 2011.

During GDA, regulators have asked hundreds of technical questions of Areva and Westinghouse with the figure increasing exponentially in the last three months. This indicates that the pace of work has picked up dramatically since the HSE attained full staffing levels in recent weeks.

The queries can be divided into several main areas, with HSE finding shortfalls of information from vendors in some of these. Should the HSE's technical queries remain unsatisfied during the process, these issues could be escalated to a 'regulatory issue' which could ultimately result in 'exclusions' from GDA. This means a reactor could be accepted as safe for use except for the excluded area, which would have to be licensed under a separate process.

For both reactors, the HSE raised a regulatory issue in February last year concerning factors such as dose assessment, waste strategy and impact on non-human species and requested a more detailed demonstration that its demands are being met. This was closed out by both vendors within six weeks.

The HSE has since identified potential exclusions for AP1000 in the areas of civil engineering and structural integrity. A company spokesman told World Nuclear News: "The classification of these areas as 'potential exclusions' reflects that fact that there remains substantial work to be done on these topics to demonstrate to the HSE that the design is acceptable. We are in the process of doing that work, and remain confident that in these respects - as in all others - the UK regulators will conclude that the AP1000 is safe to operate."

For EPR there is a regulatory issue and corresponding potential exclusion concerning control and instrumentation (C&I). Specifically, the HSE remains to be convinced that the systems for control and that for instrumentation are sufficiently independent and diverse. The HSE has told Areva that the C&I architecture appears overly complex and may rely too much on computer-based systems which have a high degree of connectivity."
(source: http://www.world-nuclear-news.org)

2009-05-02: Win of sites for nuclear built

EDF, a French electricity company, and a consortium of RWE and E.ON, two German firms, won sites on which to build new nuclear-power plants in Britain in an auction that raised £387m ($571m) for the government. EDF won one site at Bradwell, in Essex. RWE and E.ON won sites at Oldbury in Gloucestershire and Wylfa in Wales. A full list of up to 11 sites will be finalised later in the year.
(source: The Economist)

2009-04-15: Potential new UK plant sites named

The UK government has published a list of eleven potential sites for new nuclear power plants, which have been nominated through the Strategic Siting Assessment (SSA) process.
At the end of January, the government gave the nuclear industry two months in which to nominate sites for the first wave of new nuclear power plants. The call for nominations came as the criteria were published against which potential sites will be assessed.
The Department of Energy and Climate Change (DECC) has now published the list of nominated sites "after vetting all applications to ensure they were credible, that the sites could be operational by 2025 and that the nominator had raised public awareness of their intention to nominate."

The sites have been nominated by Electricite de France (EdF), EOn and RWE, and by the Nuclear Decommissioning Authority (NDA), which owns some of the land.

Ed Miliband, the UK's energy and climate change minister, said: "This is another important step towards a new generation of nuclear power stations. I want to listen to what people have to say about these nominations and I encourage people to log-on to our website, read the information and let us have their comments. We will consider this alongside the advice of our independent expert regulators."

Following a one-month public comment period, information from the public will be used alongside the advice of regulators and other specialists. Sites which are judged to be potentially suitable will be included in the draft National Policy Statement (NPS) on nuclear power which will be published later this year for public consultation. This is part of the new planning system under the new Planning Act 2008. The NPS will set the policy framework for the new independent Infrastructure Planning Commission's decisions on new nuclear power.
(source: world-nuclear news)

2009, April: Next stage for nuclear new-build

The next stage in the UK consideration of new-build nuclear began today with the launch of a government consultation on siting. Further details are available under:
(source: no-nukes-eur@lists.foei.org)

2002: Security inspections abandoned due to staff shortage

In June 2002 security inspections of Britain's nuclear facilities to ensure they are safe from terrorist attack have been abandoned because of a chronic staff shortage.
The government's own director of civil nuclear security has admitted that a recruitment crisis in his office has forced him to cancel full security checks at 22 of the 31 nuclear power stations and waste reprocessing stations it regulates.
Buckland-Smith also said his agency had discovered "deficiencies" in the security arrangements adopted by a number of facilities, though he did not give full details.

2003, January: Discussion about governmental take-over of Britains NPPs

A Cabinet sub-committee was discussing taking Britain's nuclear power stations - including Torness - back into public ownership. The sub-committee was considering giving the Government the power to take control of the struggling nuclear power group British Energy.
Despite a huge £650 million loan from the government, the company is still facing bankruptcy next month.
The firm could share a fate similar to Railtrack - ministers are considering converting it from a private company to a non-profit making organisation like Network Rail.
Last month, British Energy - which produces about a fifth of the country's electricity - revealed losses of US$ 518 million before taxes in the six months to September 2002. It has been hit hard by a 40 % decline in electricity prices since the wholesale power market was liberalised last year.

New laws are set to be rushed through the Commons to allow British Energy, privatised by the Thatcher government, to be taken into administration.
Senior ministers were considering the issue at a special Cabinet sub-committee, which is drawing up a new energy white paper, today. It is expected to announce a freeze on the building of new nuclear power stations and to outline plans to increase the use of greener fuels to produce electricity.

David King, the government's chief scientist, made a last-ditch attempt tomorrow to persuade a cabinet committee to support a new generation of nuclear power stations, despite opposition from ministers.
The committee's decision is crucial to the content of the white paper on energy due to be published next month.
The nuclear camp was in disarray before Christmas after the collapse of British Energy and the bankruptcy of British Nuclear Fuels.
A new generation of nuclear stations favoured by Prof King would require government subsidy and intervention to force through planning permission against strong public opposition. Nuclear stations are closing down progressively and the 20% of electricity they produce is being sold at a loss. Extra power would have to come from gas or coal as renewables could not account for 20% of supplies.
King's opponents point out that they hoped for energy efficiency gains of 20% by 2010, rising to 40% by 2020, would solve that problem. They also want to increase the low target of 10% renewables by 2010. The white paper, as drafted, suggests raising this to 20% by 2020 - a figure regarded as hopelessly timid by environment groups and energy companies, which think 30% is reasonable.
Anti-nuclear ministers, realising it will be difficult to reject nuclear power altogether with Mr Blair favouring Prof King's position, are hoping to buy time by suggesting the nuclear option should be reviewed again after five years.

Sites With Nuclear Facilities

siteplantreactor typconstruction startoperation startshut down
AldermastonAldermastonweapon factory
BerkeleyBerkeley-AGCR 140 Magnox195719621989
Berkeley-BGCR 140 Magnox195719621989
BradwellBradwell-1GCR 150 Magnox195719622002
Bradwell-2GCR 150 Magnox195719622002
ChapelcrossChapelcross-1GCR 50195519592004
Chapelcross-2GCR 50195519592004
Chapelcross-3GCR 50195519592004
Chapelcross-4GCR 50195519602004
DounreayDounreayFBR 250196619751994
Dounreay complexFBR reprocessing plant
Dounreay FR 1FBR 15195519621977
DungenessDungeness -A1GCR 270 Magnox196019652006
Dungeness -A2GCR 270 Magnox196019652006
Dungeness -B1AGR 62519651983
Dungeness -B2AGR 62519651985
HartlepoolHartlepool-1AGR 62519681984
Hartlepool-2AGR 62519681984
HeyshamHeysham -1BAGR 62519701984
Heysham -2AAGR 62019801988
Heysham -2BAGR 62019801988
Heysham- 1AAGR 62519701983
Hinkley PointHinkley Point AGCR 2 * 266 Magnox195719651999
Hinkley Point BAGR 2*62519671976
HunterstonHunterston-A1GCR 160 Magnox195719641990
Hunterston-A2GCR 160 Magnox195719641989
Hunterston-B1AGR 62519671976
Hunterston-B2AGR 62519671977
Hurd DeepHurd DeepDumping Site
OldburyOldbury -1GCR 360196219672012
Oldbury -2GCR 360196219682011
SellafieldCalder Hall-1GCR 50 Magnox195319562002
Calder Hall-2GCR 50 Magnox195319572002
Calder Hall-3GCR 50 Magnox195519582002
Calder Hall-4GCR 50 Magnox195519592003
Sellafield Mox Plantreprocessing complex
Thorpreprocessing plant
WindscaleAGR 30195819631981
SizewellSizewell A-1GCR 290 Magnox196119662006
Sizewell A-2GCR 290 Magnox196119662006
Sizewell-BPWR 120019881995
Torness PointTorness Point-1AGR 64519801988
Torness Point-2AGR 64519801989
TrawsfynyddTrawsfynydd-1GCR 250 Magnox195919651991
Trawsfynydd-2GCR 250 Magnox195919651991
WinfrithWinfrithSGHWR 90196319671990
WylfaWylfa-1GCR 590 Magnox19631971
Wylfa-2GCR 590 Magnox196319712012