Building nuclear power plants still takes the longest. Especially if you want to produce the same amount of energy that will be needed in the coming years. Currently, nuclear power plants supply about 9% of the electrical energy used worldwide — and it has taken us from 1950 until today to get there. Why should it suddenly be faster and more elegant now? We also don’t have the money to pursue both in parallel.
Yes, I know China and to some extent South Korea build nuclear power plants faster. But even there, some plants have taken up to eleven years to build, and others that were built quickly only achieve a capacity factor of 60%. At least in China’s case, many of the conditions cannot be directly transferred to Western countries. Space, social and political circumstances, and other factors are simply not the same everywhere as in China. Moreover, even China, whose share of nuclear energy in its electricity mix is around 4.5%, is finding that renewables are much faster and cheaper.