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What is nuclear energy?
Nuclear energy uses a controlled nuclear reaction to heat a fluid (for example, water) which can drive an electricity generator. The process currently used in nuclear power stations to generate energy is nuclear fission. Nuclear fusion is a possible new method of generating energy but it is 'a technological long shot.'1 It may be noted that nuclear fission is also the process which produces the explosive energy of atomic bombs. At present about a third of electricity in the UK is generated by nuclear power stations2.

What are the consequences of using nuclear energy? (See also Poster 1)

Cost of production
Nuclear power stations currently in use in the UK are ageing and will need to be replaced within the next 20 - 40 years if Britain opts for nuclear energy as the main source of generating electricity. Existing reactors will need to be decommissioned, new ones will need to be built and maintained and nuclear waste disposed of. The combined cost of these processes will require massive public funding, although it is argued that building a large number of nuclear power stations will help to reduce costs.

Environmental impact
The main argument in favour of nuclear energy, and the reason why the UK government is thought to favour developing it, is that nuclear power stations produce few or no greenhouse gases in their operation and are in that respect 'clean' sources of energy. Greenhouse gases will be generated in the production and transport of the components of nuclear power stations but that is true in one way or another for all sources of energy. Although it is estimated it will take 10 years before any new nuclear power stations are fully commissioned, it is argued that they will still be ready sooner than renewables to meet the need for environmentally-friendly energy.

One of the strongest arguments against nuclear energy is also environmental: there is no agreement on how to dispose of nuclear waste, some of which will remain dangerously radioactive for 10,000 years. One of the waste products of nuclear fission is plutonium, an element which does not occur naturally, and which is highly toxic
Nuclear power stations use uranium as the fuel whose fission generates power. A kilogram of natural uranium used in a typical reactor yields around 20,000 times as much energy as a kilogram of coal and a kilogram of enriched uranium 160,000 times as much3. It is therefore a highly efficient fuel and it is estimated that it is unlikely to run out in the near future. At the same time, it is a finite resource, and a large expansion in the building of nuclear power stations worldwide might alter this scenario.

Health and Safety Issues
Nuclear energy raises serious health and safety issues at all stages in the process. The mining of uranium releases radioactivity into the environment and may expose miners to dangerous levels of radioactivity. Nuclear waste remains potentially hazardous for centuries. While the safety procedures for the modern nuclear industry in the West are stringent, they did not prevent the accident at the Three Mile Island power station in the US in 1979 nor the catastrophic explosion of the Chernobyl nuclear reactor in the Ukraine in 1986. Moreover, nuclear operations, particularly those associated with spent fuel reprocessing, involve the permitted routine release of low level radioactive materials, the effects of which are not fully understood4. The current tendency to site nuclear power stations on the coast could prove a problem if sea-levels rise (see Article 1) There are also political dangers (see below).

Political issues
Accessibility: As suggested in Factsheet 2, keeping the production of energy in all its stages within a country is an attractive proposition. Nuclear energy is viewed by some as a home-based means of generating energy which does not rely on uncertain supplies: however, so long as available sources of uranium are needed for nuclear power stations in the UK, nuclear energy is vulnerable to the same problems of outside political control of the main energy source as non-renewables.
Vulnerability to terrorism: Nuclear power stations are vulnerable to terrorist attack from the air although this may not be a significant threat. However, the proliferation of nuclear power stations means an increased risk of terrorists acquiring nuclear material illegally to make 'dirty' bombs.
Military uses: The existence of nuclear power stations allows the production of enriched uranium, which caan be used to make atomic bombs. So long as any country maintains nuclear power stations there is the possibility of that country producing nuclear weapons: hence the concern over Iran's nuclear programme. People who are opposed to the use of nuclear weapons have the same concern about proposals to embark on a major nuclear energy programme in the UK.


page last updated 31 May 2006


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