HomeSciencePhysics (continued)What is Nuclear Fusion?
Science·2 min·Updated Mar 14, 2026

What is Nuclear Fusion?

Nuclear Fusion

Quick Answer

Nuclear fusion is a process where two light atomic nuclei combine to form a heavier nucleus, releasing a large amount of energy in the process. This is the same reaction that powers the sun and other stars.

Overview

Nuclear fusion occurs when two small atomic nuclei, typically isotopes of hydrogen, collide at high speeds and merge to form a single, heavier nucleus. This process releases a tremendous amount of energy, far greater than what is produced by nuclear fission, which is the splitting of heavy nuclei. Fusion is the energy source that powers stars, including our sun, where hydrogen nuclei fuse to create helium and release light and heat in the process. The conditions required for nuclear fusion are extreme temperatures and pressures, which are found in the core of stars. In laboratories on Earth, scientists attempt to recreate these conditions using devices like tokamaks, which use magnetic fields to contain hot plasma. An example of this is the ITER project in France, which aims to demonstrate the feasibility of fusion as a large-scale energy source. The significance of nuclear fusion lies in its potential as a clean and virtually limitless energy source. Unlike fossil fuels, fusion produces minimal radioactive waste and does not emit greenhouse gases. If harnessed effectively, it could provide a sustainable energy solution for the growing global population while reducing our reliance on polluting energy sources.


Frequently Asked Questions

The primary fuels for nuclear fusion are isotopes of hydrogen, specifically deuterium and tritium. These isotopes are chosen because they have the right properties to facilitate the fusion process at achievable temperatures.
Nuclear fusion combines light nuclei to form a heavier nucleus, while nuclear fission splits heavy nuclei into lighter ones. Fusion releases more energy than fission and produces less long-lived radioactive waste.
Currently, nuclear fusion is not yet used for commercial energy production, as it is still in the experimental stage. However, ongoing research aims to make fusion a viable energy source in the future.