TL;DR
using/generating energy always emits heat as waste and there is an upper limit of efficiency that we are not that far from. if that energy was generated via something that is not a natural heat gradient for the earth’s surface there is a net increase of heat in the earth system simply by generating and using energy.
a lot of energy sources fall into this: fossil fuel, nuclear, geothermal, etc. two that don’t are (certain types of) solar and wind, since their energy would eventually be dissipated onto earth’s surface whether we intercept or not.
that waste heat is currently estimated to be ~2% of the heating power caused by global warming, so already significant. we essentially have an upper limit on sustainable energy usage on earth (and therefore an avg per person usage) or we will have Global Warming 2: Waste Heat Boogaloo.
Sounds like a Solarpunk novel to be written. Let’s put all incineration activities away. Yet, space colonization is here and serves capital accumulation, first and foremost. There’s also the tiny part where rockets have to be shot to outer space with a little bit of energy and waste heat.