What are the advantages of a fusion reactor over a fission reactor? What are the practical difficulties in operating a large-scale fusion reactor?

Nuclear fission involves the splitting of a heavy, unstable nucleus into two lighter nuclei. Nuclear fusion, on the other hand, is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles (neutrons or protons). The difference in mass between the reactants and products is manifested as the release of large amounts of energy.

The following points highlight the advantages of fusion reactors over fission reactors: 1. Abundant fuel supply: Fusion reactors utilize isotopes of hydrogen, namely deuterium and tritium, which are broadly available. In comparison, fission reactors depend on uranium which is limited and requires mining.2. No high-level nuclear waste: Fusion does not produce high-level nuclear waste, unlike fission reactors.3. Inherent safety: Fusion reactors are inherently safe since the fusion chain reaction automatically stops if the conditions are not right. Fission, in contrast, can lead to a runaway reaction, if not controlled.4. No risk of nuclear weapons proliferation: Fusion does not require enriched material and does not produce plutonium, so it reduces the risk of nuclear weapons proliferation compared to fission.

Here are some of the practical difficulties in operating a large-scale fusion reactor: 1. Maintaining high temperature: In order to overcome the electrostatic forces that keep two nuclei apart, a very high temperature is required in fusion reactors (approximately six times the temperature of the Sun’s core)2. Containment of plasma: Magnetic confinement and laser inertial confinement are needed to keep the plasma from contacting the reactor wall.3. Neutron radiation: Fusion reactors produce high-energy neutrons, which can cause activation of materials, making them radioactive and posing potential hazards.