Nuclear power requires only a tiny fraction of the land required by wind and solar to produce the same amount of electricity. In theory, deep geothermal is just as good if not better but supercritical deep geothermal depends on technological breakthroughs that haven't happened yet. Nuclear fusion works by compressing two very light atoms such as hydrogen or helium together to form a new heavier atom. This process releases energy while also overcoming many of the drawbacks of nuclear fission.