There was an article years ago about applying real science to Traveller in, I think, The Space Gamer. One of the more interesting bits was a discussion about engine or reactor efficiency vs. the energy output of the engines and what happens to the waste heat. The speculation was that you'd turn your 100 ton Seeker into a pile of molten metal seconds after turning on your Power Plant. Of course that was Classic Traveller, with computers the size of old mainframes. :-)
It's never gotten better with any of the later incarnations, either. There were lots of online discussions of how a vessel might be able to shed gigawatts, or even terawatts of energy. Eventually, the conclusion was, "it just happens, and your starship doesn't glow like a small sun across the electromagnetic spectrum.