Nuclear power is possibly the most contentious and emotive of all methods of energy production, due to the nature of the material involved and long term consequences of accidents. Nuclear power stations currently produce about 14% of Britain's electricity.
There has been a significant drop in this figure since 2006 (around 20%) because several nuclear plants have been shut down for repairs for extended periods.
Uranium is a naturally occurring radioactive element, left over from Earth's formation. It can be used in nuclear power production because if a free neutron collides with the nucleus of a Uranium atom, the nucleus splits (fission) into two smaller atoms plus one free neutron. This free neutron can then cause another fission to occur (a chain reaction). As the two new atoms weigh less than the original Uranium atom, an enormous amount of energy is also released.
The energy produced by the splitting of the Uranium nucleus in the power plant (the reactor) is used as a heat source. This turns water into steam, which drives a turbine. The turbine spins a generator to produce electricity. The reactor is sealed inside concrete and steel to prevent radioactive gases and fluids leaking from the plant.
Calder Hall, Cumbria, was the world's first nuclear power station to produce electricity. It opened in 1956. Currently there are nineteen reactors operating in Britain with many due to close over the coming years.
The British Government confirmed in 2008 that it would back a new generation of nuclear power stations. John Hutton, former Secretary of State for Business Enterprise and Regulatory Reform told Parliament that the case in favour of nuclear power was “compelling” and that he hoped the first new station would be up and running well before 2020.
Proponents of nuclear power say that, without it, the UK will not be able to meet its energy demands whilst preventing carbon dioxide emissions from increasing. They also argue that nuclear power has a crucial role to play in helping the UK to avoid becoming reliant on oil and gas imports from unstable countries.
The critics of nuclear power argue that it has not traditionally been very clean. Waste from the power plants is toxic for many centuries and there is no safe way to store it permanently or dispose of it. Transporting nuclear fuel can also be risky and there remains the risk of an accident such as that which affected Chernobyl in 1986.
The UK would not be alone if it decided to opt for more nuclear power stations. Nearly all countries have been affected by rises in oil and gas prices, and many are looking for alternatives. Among countries currently building new plants, or considering doing so, are the US, Russia, Japan, India and China.
Alternative energy sources: