Start Here I think your answer is somewhere in the IEC ELV standards.

Plus one for Ice Pirates. It gave us Space Herpes

They take the waste heat from nuclear decay and convert it to electricity through the use of a peltier device. Those work off of differential temperature and are pretty inefficient to begin with. Unmderated Nuclear decay doesn’t produce a lot of heat at one time, which is why reactors use a moderator to increase the power output.

Well, I work in commercial nuclear power, and I have since 2010, so…yeah, I’m super creative.

This article has a good breakdown. The biggest issue is efficiency. RTGs are around 5-9% efficient. Standard steam cycle generators are around 30% (see this article ) . You get much more usable energy from fuel used in a commercial reactor vice a RTG.

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