Energy from nuclear fusion


Energy from nuclear fusion

In a nuclear fusion reaction, two atomic nucleus are forced to combine with each other to form a single nucleus. This requires a large amount of energy, slightly less than the sum of the initial masses of the two starting nuclei.

During nuclear fusion, this difference in mass is transformed into energy, following the famous equivalence between mass and energy defined by Einstein.
The nuclei of lighter atoms can be fused together more easily. For this reason hydrogen, the most widespread element in the universe, is considered the best nuclear fuel.

The energy that can be obtained from the fusion of two isotopes of hydrogen such as deuterium and tritium is significantly greater than the energy required to start the fusion process. Also for this reason the fusion of deuterium and tritium is currently the focus of much research on controlled fusion.

However, this is not the only fusion that can be obtained in a controlled environment.

Energy from nuclear fusion

Some possible fusions currently under consideration would even make it possible to avoid the emission of neutrons during the fusion process.

A flux of neutrons produced by the fusion could lead to radioactive pollution of the reactor components, as is already the case for reactors that exploit the nuclear fission process.
However, the first step for research in this sector involves the construction of a nuclear reactor capable of generating controlled fusion of deuterium and tritium.

In September 2021, the American company Commonwealth Fusion Systems, of which the Italian Eni is the largest shareholder, built and tested a 1:1 scale prototype of a magnet based on HTS superconductors. The experiment demonstrated that it is possible to construct a fusion chamber in which plasma confinement is ensured by high-temperature superconducting magnets.

This type of fusion chamber will allow the construction of an experimental reactor, called SPARC, smaller than the other prototypes under development. The data collected by SPARC will make it possible to build ARC, the first industrial pilot plant capable of reaching the temperatures necessary to make possible the controlled fusion of deuterium and tritium. According to CFS forecasts, the SPARC reactor could start operating as early as 2025.