So I’ve got an idea, no no, no boiling water required.

We build a lever, like a giant one, and attach a system of gears to harness all the energy from when the lever is pressed, then we go up into space and carve an asteroid into bits and throw them using science to accurately hit the lever, and produce electricity, easy peasy. Only need good old fashioned kinetics, and none of this newfangled boiling water tech.