How do nuclear reactors harness energy from fission processes?

Nuclear reactors harness energy from fission processes by converting the heat released into electricity.

In a nuclear reactor, the process of nuclear fission is utilised to generate energy. Nuclear fission is a reaction in which the nucleus of a heavy atom, such as uranium-235 or plutonium-239, is split into two or more smaller nuclei along with a few neutrons. This process releases a significant amount of energy in the form of heat and radiation.

The fission process begins when a neutron strikes the nucleus of a uranium-235 or plutonium-239 atom, causing it to split and release more neutrons. These newly released neutrons then strike other uranium or plutonium atoms, causing them to split and release even more neutrons. This creates a chain reaction, which is carefully controlled in a nuclear reactor to prevent it from escalating into a nuclear explosion.

The heat generated from this chain reaction is used to heat water, producing steam. This steam is then used to drive a turbine, which is connected to a generator. As the turbine spins, it turns the generator, producing electricity. This is a similar process to that used in conventional power plants, where fossil fuels are burned to heat water and produce steam.

Control rods made of materials that absorb neutrons, such as boron or cadmium, are used to control the rate of the fission reaction. By adjusting the position of these control rods, operators can increase or decrease the number of neutrons available to sustain the chain reaction, thereby controlling the amount of heat produced.

The energy produced by nuclear fission is incredibly potent. A small amount of uranium or plutonium can produce a large amount of energy. However, the process also produces radioactive waste, which must be carefully managed to protect people and the environment. Despite this, nuclear power is considered a low-carbon energy source, as it does not produce greenhouse gases like fossil fuel power plants do.