It's not just that. When you build reactors in series, you have economies of scales in term of accumulated expertise, amortising R&D costs, etc. France for inst

It's not just that. When you build reactors in series, you have economies of scales in term of accumulated expertise, amortising R&D costs, etc. France for instance finished building up its nuclear capacity at the end of the 80s, and every reactor built since has been unique, extremely costly and behind schedule. But the day they will replace their whole estate, the economics will likely be very different.