What Is a Nuclear Power Plant

A nuclear power plant is a thermal power station where heat is generated by the reaction of radioactive materials in the nuclear reactor. This heat is used to produce steam, which is then directed to the turbine to produce electricity. Presently, around 430 nuclear power plants are functioning in different countries worldwide.

A thermal power station is a plant where the heat is utilised to produce electricity. The heat is used to convert the water into steam that strikes the blades of the turbine and runs the generator to produce electricity.

To understand the working of nuclear power plants, we need to understand some terms related to nuclear energy. These terms are as follows:-

1. Nuclear fission
2. Nuclear fusion

The terms are further outlined in the following section.

1. Nuclear fission:

Nuclear fission is when the nucleus of an atom splits into two smaller nuclei due to the collision between the neutrons and the nucleus of an atom. This releases a large amount of energy, leading to the emission of gamma rays and neutrons. This energy is utilised to produce electricity in the nuclear power plant to run the thermal power station.

2. Nuclear fusion:

Nuclear fusion is the process of fusing or combining two or more nuclei to form a new, heavier nucleus. A large amount of energy is released in this process that depends upon the mass of the reactants and the products of the reactions.

Nuclear Power Plant

The principal components of a nuclear power plant are as follows.

1. Nuclear reactor
2. The heat exchanger (steam generator)
3. Steam turbine and generator
4. Condenser

Working of a nuclear power plant

Nuclear power plants work similarly to thermal power stations. The difference merely lies in the source of energy. A nuclear power plant utilises radioactive material like uranium to generate energy, whereas a thermal power station utilises coal. Now the energy released by the nuclear reactor is used to generate steam by using heat exchangers. 

The superheated steam is allowed to strike the turbine to rotate its blades. The turbine shaft is connected to the generator, which helps produce electricity.

Components of nuclear plant

• Nuclear Reactor – Nuclear reactor is the component of the nuclear power plant which generates the heat by the nuclear fission of the radioactive material uranium 235.

Uranium is present in the tubes present in the core of the reactor. Neutrons are bombarded on the uranium, splitting it into three or more neutrons.

The moderator controls the speed of neutrons, which is heavy water D2O. The neutrons strike with heavy water molecules to slow down its speed.

Control rods are also utilised to control the chain reactions. The control rods are dipped into the water, and the control rods absorb the extra neutrons. Therefore, only one electron strikes and a stable reaction takes place.

1. Heat exchanger – A heat exchanger transfers the heat generated in a nuclear reactor absorbed by heavy water to the normal water to generate superheated steam. After losing its heat, heavy water is pumped into the nuclear reactor, and the cycle continues.

• Turbine and Generator –  The superheated steam now strikes the turbine’s blades that are coupled with the generator shaft. When turbine blades rotate, the generator shaft also rotates and produces electricity.

• Condenser – The condenser helps convert high-temperature steam to low-temperature water. This hot water flows in the cooling towers and is passed from the plates. The water comes in contact with the atmosphere and loses its energy. This reduces its pressure and temperature. After that, it is pumped again to the heat exchanger to continue the cycle.

Conclusion

We learnt in this article how heat is generated by the nuclear reactors in nuclear power plants. We also learnt how the nuclear reactor is connected to thermal power stations to produce electricity.