Energy Institute Knowledge Service team;
This Energy Insight on nuclear will cover:
- How nuclear energy is produced
- Consumption and production
- Nuclear energy in the UK
- Nuclear safety
- Organizations involved in the nuclear industry
- Further reading
How is nuclear energy produced?
Fission and fusion
There are two fundamental nuclear processes considered for energy production: fission and fusion.
Fission is the energetic splitting of large atoms such as Uranium or Plutonium into two smaller atoms, called fission products. To split an atom, you have to hit it with a neutron. Several neutrons are also released which can go on to split other nearby atoms, producing a nuclear chain reaction of sustained energy release. This nuclear reaction was the first of the two to be discovered. All commercial nuclear power plants in operation use this reaction to generate heat which they turn into electricity by heating water which turns to steam to drive turbines the same way it is in other thermal power stations.
Fusion is the combining of two small atoms such as Hydrogen or Helium to produce heavier atoms and energy. These reactions can release more energy than fission without producing as many radioactive by-products. Fusion reactions occur in the sun, generally using hydrogen as fuel and producing helium as waste. This reaction has not been commercially developed yet and is a serious research interest worldwide, due to its promise of nearly limitless, low-emmission, non-proliferative energy.While almost all forms of energy can be misused, it can be argued that nuclear fusion is as safe as it can be in that nuclear fusion for power generation does not typically use fuels that can be made into nuclear weapons. Likewise, fusion for power generation does not produce radioactive materials that can be used to make weapons.
Fission and fusion
At present rates of production and demand, nuclear energy provides an important percentage of the global “energy mix.” The energy mix is a group of different sources of primary energy from which secondary energy - usually electricity - is produced for direct use. The graph above shows how energy consumption has been dominated by fossil fuels, oil, coal and natural gas, with renewables, headed by hydro followed by nuclear and finally other renewables playing a relatively small part in the global energy picture at the present. Given the importance of non-carbon generation in future “Green” energy projects, nuclear energy has an important part to play in clean energy supply and security.
Until the early 2000s nuclear generation rose to around 3% of the total since when it has flatlined. Other Renewables, on the other hand, after several decades when there was little change from under 1% of total consumption, started to rise slowly from 2000 with a fairly steep increase from 2010.
Global nuclear energy consumption - million tons of oil equivalent (mtoe) 2017: by area:
| || 2007|| 2017|
% of World
| of which|| |
| North America|| 215.4|| 216.1|| 36.2|| USA|| 191.7|
| South and Central AmericaEurope|| 4.4|| 5.0|| 0.8|| Brazil|| 3.6|
| Europe|| 218.0|| 192.5|| 32.3|| France|| 90.1|
| CIS|| 57.7|| 65.9|| 11.1|| Russia|| 46|
| Middle East|| -|| 1.6|| 0.3|| Iran|| 1.6|
| Africa|| 2.6|| 3.6|| 0.6|| South Africa|| 3.6|
| Asia Pacific|| 123.3|| 111.7|| 18.7|| China|| 56.2|
| WORLD TOTAL|| 621.4|| 596.4|| 100|| || 392.8|
(BP Review of World Energy 2018)
As the above table shows, over 10 years between 2007 and 2017, there has been a fairly large decline in nuclear energy consumption worldwide although this has been entirely in Asia/Pacific and Europe. In the Middle East and Africa, nuclear energy production has been dominated entirely by 2 countries, Iran in the former and South Africa in the latter.
This needs to be seen in the light of the availability of abundant, and far cheaper, hydrocarbon supplies in the Middle East where Iran alone has started to develop its nuclear energy capacity to power an already huge demand both domestic and industrial.
In Africa, on the other hand, the long build time, the huge investment needed and the problems of nuclear waste disposal have stood against the development of the nuclear industry with only South Africa going ahead with development.
Nuclear energy in the UK
History of UK nuclear energy
Britain in the 1940s and 50s was in the forefront of commercial nuclear power development with the world’s first nuclear reactor, Calder Hall 1, starting up in the UK in 1956. This was followed by the building of 26 Magnox reactors. Design life of the original reactors was 20 years but most were in operation for far longer than that.
The Magnox reactors
, named after the magnesium alloy (magnox) used to encase the fuel, natural uranium metal, were followed by the Advanced Gas-Cooled Reactors which ushered in the second phase of the UK’s nuclear programme. The world's last Magnox reactor, Wylfa 1 in Anglesey, was closed in 2015. (Magnox Ltd is also the name of the company that operated the Magnox sites in the UK and is now a nuclear decommissioning company.)
Britain currently has 15 reactors (14 advanced gas-cooled reactors (AGR) and one pressurised water reactor (PWR)) that generate around a sixth of the UK's electricity. However, about half of this capacity will have been closed down by 2025.
Work has started on one new plant, Hinkley Point C
, intended to provide 7% on the UK’s electricity. Apart from this project, due to be completed by 2025, there are only 2 other nuclear plants, Bradwell B
and Sizewell C
, under consideration with 3 other possible plants, Moorside
, Wylfa Newydd
, shelved at the moment. In the case of Wylfa Newydd, after a billion pounds had been spent on the project, one of the companies involved, Horizon Nuclear Power
, said they were keeping open the option of resuming at some time in the future.
Nuclear plants operating at present (May 2019)
| Plant || Type || 2019 capacity (MWe net) || First power || Expected shutdown |
|Dungeness B 1&2 || AGR || 2 x 520 || 1983 & 1985 || 2028|
| Hartlepool 1&2 || AGR || 595, 585 || 1983 & 1984 || 2024 |
| Heysham I 1&2 || AGR || 580, 575 || 1983 & 1984 || 2024|
| Heysham II 1&2 || AGR || 2 x 610 || 1988|| 2030|
| Hinkley Point B 1&2 || AGR || 475, 470 || 1976|| 2023|
| Hunterston B 1&2 || AGR || 475, 485 || 1976 & 1977 || 2023|
| Torness 1&2 || AGR || 590, 595 || 1988 & 1989 ||2030 |
| Sizewell B || PWR || 1198 || 1995||2035 |
UK Magnox reactors
The world's first commercial nuclear power station was opened at Calder Hall in 1956. The Magnox reactors were initially dual-purpose, combining power generation with plutonium production for military purposes.
| Reactor|| MWe net || Startup || Status |
| Berkeley 1 || 138|| 1962 || Shutdown 1989|
| Berkeley 2 || 138|| 1962 || Shutdown 1988|
| Bradwell 1 || 123|| 1962 || Shutdown 2002|
| Bradwell 2|| 123|| 1962 || Shutdown 2002|
| Calder Hall 1 || 50 || 1956|| Shutdown 2003|
| Calder Hall 2|| 50 || 1957|| Shutdown 2003|
| Calder Hall 3|| 50 || 1958|| Shutdown 2003|
| Calder Hall 4 || 50 || 1959|| Shutdown 2003|
| Chapelcross 1 || 49|| 1959 || Shutdown 2004|
| Chapelcross 2 || 49 || 1959 || Shutdown 2004|
| Chapelcross 3 || 49|| 1959 || Shutdown 2004|
| Chapelcross 4|| 49|| 1960|| Shutdown 2004|
| Dungeness A1 || 225|| 1965|| Shutdown 2006|
| Dungeness A2 || 225|| 1965|| Shutdown 2006|
| Hinkley Point A1 || 235|| 1965|| Shutdown 2000|
| Hinkley Point A2 || 235|| 1965|| Shutdown 2000|
| Hunterston A1 || 160|| 1964 || Shutdown 1990|
|Hunterston A2|| 160|| 1964 || Shutdown 1989|
| Oldbury 1 || 217|| 1967|| Shutdown end Feb 2012 |
| Oldbury 1 || 217|| 1968|| Shutdown mid-2011 |
| Sizewell A1 || 210|| 1966|| Shutdown 2006 |
| Sizewell A2 || 210|| 1966|| Shutdown 2006 |
| Trawsfynydd 1 || 196|| 1965|| Shutdown 1993 |
| Trawsfynydd 2 || 196|| 1965|| Shutdown 1993 |
| Wylfa 1 || 490|| 1971|| Shutdown Dec 2015 |
| Wylfa 2 || 490|| 1971|| Shutdown April 2012 |
| TOTAL - 26 || || || |
Brexit and nuclear energy
In mid-February 2019, it was announced that the UK has brokered deals with Australia, Canada, the United States and the International Atomic Energy Agency (IAEA) that safeguard continuity for civil nuclear trade following leaving the EU. Arrangements with Japan that are already in place will also be maintained but more talks will have to be held. Although leaving the EU could affect the UK’s nuclear power operations, industry insiders believe that Brexit uncertainty was a factor in Hitachi’s decision in 2019 to suspend work on the Wylfa nuclear plant in North Wales, though the company itself cited economic concerns.
The Brexit effect on UK nuclear
Husseini, Talal. UK to leave Euratom after Brexit, despite uncertainty. November 2018
There have been three major recorded nuclear accidents:
– 1979 – Contained following an reactor meltdown and a small amount of radiation leakage.
– 1986 – An explosion and meltdown where there was no provision to contain the spread of contamination which spread over a large area of Europe. Over 300,000 inhabitants within an exclusion zone evacuated. The exclusion zone still enforced -Although some tours are authorised
– 2011 – an earthquake and tidal-wave severely damaged the cooling systems of several reactors leading to radioactive pollution leaking into the atmosphere and radioactive water overflowing into the sea.
Not everyone is happy about Nuclear Energy and there is an ongoing debate about the relative merits of this controversial form of energy:
Nuclear power - the problems Greenpeace UK
Our positionpaper on nuclear power Friends of the Earth
Will thorium save us from climate change David Suzuki Foundation
Reaching Critical Will: Nuclear energy Women's International League for Peace and Freedom
Stop New Nuclear
Why it's time to dispel the myths about nuclear power
While the dangers of nuclear power have always been recognized much of the essential safety features have been built into the plants and practices from the beginning. The worst, known nuclear disaster, Chernobyl
, was the result of faulty design, poor operating practice and the absence of a safety backup.
, the disaster was not the result of faulty practice or design but followed on from a massive earthquake and tidal wave. In spite of the damage done, the radioactive leaks were negligible.
Nuclear waste and disposal
All forms of energy generation produce waste and this waste has to be managed to minimize any impact on human health and environmental degradation. Nuclear fuel produces a large amount of electricity from a very small amount of fuel and this waste consists of material that is radioactive in itself and also material that has been contaminated by radioactivity. This waste is divided into low, intermediate and high levels of waste.
Waste is disposed of when there is no further use for it or, in the case of high-level waste, when the radioactivity has reduced to low enough levels for it to be disposed of.. Low-level waste and much intermediate-level waste is usually disposed of underground although very low-level waste can be disposed of in the sea. High-level waste is generally disposed of deep underground.
Organisations involved with nuclear energy
Nuclear energy in the UK:
And in the USA:
SONE – Supporters of Nuclear Energy – An independent body to secure progress towards ensuring that the UK is firmly committed to having a programme of new nuclear power plants to deliver affordable, reliable and low-carbon electricity to homes and businesses. Publishes a monthly newsletter – available in the EI library
Nuclear energy related journals available in the EI library
Nuclear energy related journals available online