Currently, scientists are trying to figure out ways of controlling nuclear fusion, in the hopes that it might also be used to generate nuclear power, since it creates less radioactive waste than fission.
However, progress has been slow, as scientists have struggled to find a way to make the amount of energy obtained from the reaction viable for power production. Research into nuclear fusion began in the 1950s, yet a fusion-powered reaction still hasn't been used in a power station. Currently, just 25 "experimental" fusion reactors exist around the globe. Fusion reactors are not expected to be available for commercial use until at least 2050.
The development of fusion reactors has faced other pitfallstoo. They are extremely expensive to build, with no guarantee of success. Reaching the temperatures required for nuclear fusion, which usually occurs within the sun, on Earth is a monumental task. Evidence suggests that, in past experiments, the energy used to reach temperatures of, at the very least, 100 million degrees, has actually been greater than the energy ultimately given out out by the fusion reaction. Critics have also pointed out that fusion requires tritrium- a radioactive element that is scarcely found in nature.
Of course, there would be several positives to the use of fusion in power generation, if it can ever be controlled. The other element required in fusion- deuterium can be distilled from seawater, and the lack of a 'chain reaction' means fusion could potentially be easier to control than fission. In fission, the 'chain reaction' is the process of splitting an atom's nucleus, creating neutrons, which go on to hit other atoms' nuclei, leading them to split too. When a chain reaction occurs within a fission reactor, several methods are used to 'cool' the reactor's core, ensuring the reaction stays under control. If the zirconium "fuel rods" involved in this process ever reach a temperature where they melt, causing a nuclear 'meltdown', the reaction would essentially speed up to the extent that it could not be contained within thr reactor. In a fusion reaction, there is no risk of such an event, leading some to argue that it could be a safer form of power generation.
Overall, it seems time, and much more research, will tell if nuclear fusion can ever be a feasible method of commercial power generation.