大象传媒

Nuclear power

The main nuclear fuels are uranium and plutonium.

In a nuclear power station, nuclear fuel undergoes a controlled chain reaction in the to produce heat - nuclear energy is converted to heat energy:

  • heat is used to change water into steam in the boiler;
  • the steam drives the (heat to );
  • this drives the generator to produce electricity - kinetic to electrical energy.
Uranium fuel rods heat gas, pump through heat exchanger, heats water, produces steam, turn turbines. Core encased in thick concrete, has boron control rods and graphite moderator to regulate gas flow.
Figure caption,
Cross-section of a nuclear reactor

Nuclear and energy are the only energy resources that do not come from the Sun.

Advantages

  • Unlike fossil fuels, nuclear fuels do not emit such as carbon dioxide.
  • Nuclear fuels do not emit gasses such as sulphur dioxide which cause .
  • 1 kg of nuclear fuel produces millions of times more energy than 1 kg of coal.

Disadvantages

  • Like fossil fuels, nuclear fuels used for , such as uranium ore, are non-renewable energy resources since supplies will not last forever.
  • Although modern reactor designs are extremely safe, if there is an accident, large amounts of radioactive material could be released into the environment.
  • Nuclear waste remains radioactive and is hazardous to health for thousands of years, so it must be stored safely.
  • a nuclear power plant is extremely expensive.