Speaking of that... When people talk about limitless cheap energy from fusion reactors in 30-50 years, I wonder about goal warning from water great from all that energy consumed and turned into waste heat radiated into Earth's atmosphere.
As far as wind, you are correct, but the amount of wind energy we can harvest is limited enough that there simply won't be enough at that point assuming that trend.
Similarly with wood, at that point we would just run out of wood.
According to this: https://ui.adsabs.harvard.edu/abs/2020EGUGA..2218924S/abstra... , the albedo is of 0.23, which is a lot lower than the albedo of soil.
You can get pretty far by being extremely efficient. We keep making better and better superconductors and even have some above room temperature. Vac-trains with superconducting maglev is more efficient, in principle, than anything short of orbiting. Better materials can make dry mass near nothing.
Reversible computing requires no fundamental energy input.
Space based solar power could make sure the waste heat from electricity production is almost zero and only useful energy is pumped to the ground.
You can shade the Sun at the limit. And you can shade only the portions of the spectrum that are not biologically active, i.e. shade infrared. That's tens of Petawatts.
You can also literally build radiators at high altitudes to dump waste heat into space before it gets conducted into the atmosphere.
You can also just do more work in space instead of on the ground.
I think also we won't grow exponentially but instead linearly or quadratically. That's actually sustainable for as long as the universe would've lasted anyway.
If that doesn’t solve the problem, a culture capable of generating and using that much energy will just build space colonies, which solves the problem too.
If everyone was a vegetarian living a dutch lifestyle we’d have no issue, that’s true.