This clean technology has yet to advance very far beyond theory, but has long been the holy grail of nuclear engineering. A fusion reaction arises from plasma composed of deuterium and tritium, which are hydrogen isotopes, being fused together; releasing tremendous energy and the leftover "ash" of the reaction is helium.
The problems that are being addressed in this research are containment, and sustaining a reaction for more than millionths of a second at a time.
The nuclear plasma inside a fusion reactor must reach a temperature of two hundred million degrees Fahrenheit to force the isotopes in the suspended plasma close enough to make them fuse, and there is no material known that can stand up to contact with that temperature. As a result, a powerful magnetic field is required to suspend the reaction inside, but not touching, the reactor.