I composed a rather lengthy response for this thread, but lost it when my laptop battery died.
I'll try and reproduce some of the basic ideas now.
I want to talk a little bit about some more distant future possibilities. This is science fiction for now (so those who are turned off by that, you can stop reading now, or just keep reading with that disclamer in mind.)
I see a high, rugged mountain range in the near future that we as a civilization will have to cross. But it doesn't go on forever, and if we can get past it to the valleys on the other side we can open up possibilities for resource extraction and energy production that will provide all the room to grow that we will ever need. I'm specifically thinking about the exploitation of space-based resources. It's true that we only have a finite (very small in the grand scheme of things) amount of room to grow and materials to build with here on Earth, but there's a whole lot of space and raw material off-world that can supply economical and industrial growth well
into the future. If we make it through climate change with our tech intact (and continue to develop and improve it along the way) we may be able to stop strip mining our own home and start pulling resources and energy off of other worlds.
I did a back-of-the-envelope calculation to see roughly how much energy it would take to get material off the lunar surface back to Earth and got 50 MJ/kg (assuming a 10 km/s delta-v, which is about what the Apollo moon lander budget was I believe). That's a decent chunk of energy, but not overwhelmingly so. Much of the lunar surface is silicon, and PV cells may be manufacturable on the surface to provide that energy to rail-guns for export back. PV cells could be manufactured on the lunar surface using indigenous material, and since it's EROEI is greater than 1 (estimates I've seen vary greatly, but none have been less than 1), that energy could be fed back to produce more PV with some left over for export back to Earth or to be used in further mining. Those energy returns can take years, so the process may need to be kickstarted using nuclear (whose problems of radioactivity and waste disposal are almost irrelevant on the already high radiation environment of the dead lunar surface.) Once started, if the process could be automated, it could grow until we have more solar than we know what to do with.
Another prospect is putting large solar power stations in Earth orbit (produced on the moon because of its much shallower gravity well) for power to be beamed down to the surface using microwaves.
Controlled nuclear fusion is another contender for energy. It won't be as cheap as FF (for a very long time, if ever), but its fuel is ridiculously plentiful and very safe and it produces no CO2 during operation. The reactor vessels become somewhat radioactive after long-term use, but that radiation is short-lived (on the order of a few decades rather than millenia for fission waste). This is even within our grasp now with appropriate funding levels in place. ITER, which is currently being built in Cadarache, France, will generate 10 times more heat energy than it consumes to sustain the plasma, and it's just a testbed. A full plant will be larger and its Q value many times that. There are some dark horse contenders for fusion power that aren't based on tokamak designs that could reach breakeven sooner and much cheaper, but that's a wildcard for now.
I see the future for planet Earth as the garden planet if we can get to the other side of climate change with our tech intact to get to the point where we are harvesting resources (energy and material) from somewhere other than here. We will clean-up this planet's biosphere and recycle our waste using excess energy from these new resources and hopefully never again have to tear it up in the search for further growth.