In some future century we will hit the limits of energy per person, but it is far far far away.

right now we only extract a tiny fraction of the energy hitting the earth. and really the sun is producing much more energy than is even hitting the earth. We are SOOOOOOOO far from running out of energy. But we do have a gap in the tech to get to that energy.

when that gap is bridged, then we will not need to bother the earth in getting that energy. and it will be far better for the earth. We just need to get there without doing too much damage along the way.