We observe much faster fusion in bigger stars or in ones that run out of hydrogen. Ironically the thing that slows it down is fusion. Stars are not very dense s

We observe much faster fusion in bigger stars or in ones that run out of hydrogen. Ironically the thing that slows it down is fusion. Stars are not very dense so they produce exactly enough energy to hold some hydrogen up and no more. Contrapositively the only thing even loosely analogous to photovoltaics is much worse, and there are no natural wind turbines or water impellers. Conversion of sugars to work is pretty poor as well. I'm not bullish on fusion as a viable bulk electricity or heat source any time this century (or possibly ever on earth), but current approaches are already much better than your analogy. The stable plasma concept probably won't work without much better magnets and a whole host of other highly unlikely advances. If you want a concept that is not obviously terrible, look up Helion.