I was toying with the idea of building what *appears* to be a standard Mk2 reactor - but with the added benefit of breeding cells at the same time. I was able to get a 4-chamber reactor to run 2 uranium cells ( for power efficiency 2, and output 40 EU/t ) - while breeding 6 cells to over 50% in one cycle. It'd more than supply its own fissible material. Yay, right? Just one irk - 40EU/t is really quite low, even with the added bonus of free breeding.
So, I've been trying to get a 3-U-cell reactor working... What I'm after is a positive breeder, 2+ power efficiency minimum, that runs like a Mk2 (cold starts, full cycles) while breeding enough to be supplying itself with new cells - and all with a minimum power output of 70 EU/t. I'm of course assuming no RedPower, BuildCraft, no ice/water injectors, etc. I can get it to run 67% of a cycle before boom. Not quite enough. Is such a rector an actual impossibility?
I'm thinking it probably IS impossible.