Of the thirty countries in which nuclear power plants operate, only France, Belgium, Hungary and Slovakia use them as the primary source of electricity, although many other countries have a significant nuclear power generation capacity.hina, South Korea and India are pursuing ambitious expansions of their nuclear power capacities, with China aiming to increase capacity to at least 80 GWe by 2020, 200 GW e by 2030 and 400 GW e by 2050.