If we were able to harness the excess energy of nuclear fusion efficiently, it would likely have a major impact on humanity. Nuclear fusion has the potential to provide a nearly limitless source of clean and safe energy, as it produces power by combining light elements such as hydrogen, rather than by splitting heavier elements such as uranium, as is done in nuclear fission. This process does not produce greenhouse gases or harmful radioactive waste, and it has the potential to provide much more energy than can be obtained from fossil fuels or nuclear fission.
The widespread adoption of nuclear fusion as a primary energy source could potentially help to address many of the major challenges facing humanity, such as climate change, air pollution, and energy security. It could also enable us to power our economies and societies in a more sustainable and equitable way. However, it is important to note that there are still significant technical and logistical challenges that need to be overcome in order to make fusion energy a practical and cost-effective reality, and it is not yet clear when or if these challenges will be fully addressed.