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Energy

Alternatives to oil

Could we live without fossil fuels which currently provide 90% of the world’s energy? Click on the bar below to explore the options.
Nuclear Hydropower Hydrogen Wind Solar Others

Uranium fuel rod
A fuel rod is immersed into a reactor: Uranium is a finite resource
Nuclear power

Nuclear power plants provide about 17% of the world's electricity.

Pros

  • Nuclear power can generate large quantities of energy without releasing greenhouse gases
  • It does not depend on the weather
  • The UK's largest reactor generates the equivalent output of 1188 wind turbines. A nuclear fuel pellet, about half an inch long, provides the same amount of electricity as one and a half tonnes of coal.

    Cons

  • Spent fuel from nuclear power plants remains toxic for centuries and there is no safe permanent storage facility for it
  • Dismantling old reactors safely is highly expensive
  • Mining and enriching uranium also produces toxic waste
  • Uranium is a finite resource, although there are ways of recycling spent fuel
  • Fears of nuclear material stolen from power facilities being used by terrorists in a so-called "dirty bomb" have increased since the 11 September attacks
  • Nuclear power is currently generated from nuclear fission - splitting the nuclei of atoms. Nuclear fusion - combining atomic nuclei - is potentially cleaner because the fuels involved are different. But scientists have been trying to harness the energy from fusion for decades and some say a working fusion generator is still a lifetime away.
  • There is a close link betweeen civil and military uses of nuclear power

    How it works

    A nuclear reaction is a change in the nucleus of an atom, and can be triggered by bombarding an atom with a subatomic particle, such as a neutron or proton. In a nuclear fission reactor, a neutron strikes the nucleus of an atom with a heavy nucleus, such as a particular type - or isotope - of uranium atom. The nucleus of this atom splits, releasing huge amounts of energy, mainly in the form of heat. Other neutrons are also released, which initiate a chain reaction by striking other nuclei. Nuclear reactors control this reaction and use the heat to generate electricity.

    Nuclear fusion - also the reaction by which the Sun generates heat - is still in development. Light nuclei, such as those of isotopes of hydrogen, are combined to make heavier ones, such as helium, at very high temperatures and pressures. Large amounts of energy are released in the process but the reaction has proved to be difficult to contain and control.

    Nuclear fission power plants provide about 75% of electricity in France, a quarter in the UK and 15% in the US. More than 100 of the world's 400 nuclear power plants are in the US.

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