it requires approx 400 EU on average to make 1 UUM with maximum scrap application according to my calculations so i fully agree with Above
Besides if we ever manage to attain a technological prowess to allow a controlled break of the strong nuclear force in atomic nucleus-es we could have near infinite energy IRL too
and back on topic: if you simply have enough compressed snowballs (a renewable resource) you could theoratically (with buildcraft) allow a would be Mark V to run a full cycle without any big booms i am calling this C.A.S.U.C. for "Constantly Applied Single Use Coolants" the only downer is that it only allows a reactor with 5 chambers because the pipe has to be connected directly to the reactor block