Its also worth pointing out the scale of the problem, with a simple one stage plant design, like a very stereotypical nuke or coal plant, a cold side around outdoor temps and a hot side around 1000F means 30-something percent efficient. And at 1000F or so, the steam pressure will be handwavy a bit less than 2000 PSI.

So simply running hotter is not a realistic solution to get above 30 or so percent, not at current technology levels. That's where strange staged and cogeneration schemes are applied to boost efficiency.

Low grade process heat is surprisingly useless in practice, unfortunately. Also economics and politics smack up against engineering ideals, where massive vertical integration would result in higher efficiency but short of nationalizing all industry or allowing massive monopolies its hard to integrate a coal generating plant with a steel mill heat treatment plant and a sardine canning plant and a greenhouse all under the same roof. Maybe with infinite scaling nano-technology all industrial plants could do all things to really boost efficiency.