Frankly, I think it would be foolish to expect any fossil fuel reserves to stay in the ground. Corporations are immortal, corporations own lots of drilling tools, and as long as there is profit to be made in mining and burning fossil fuels, corporations will do it, the Earth be damned.
A lot of solarpunk visions and ideas basically take our current culture and add more solar panels and respect for life. Which isn't bad, I appreciate it. But the world we can expect is far different from today:
- temperatures will be 14 to 20 above the current average
- Sea levels are hundreds of feet higher
- almost every one of today's major cities is underwater
- Greenland and Antarctica are ice-free and temperate
- all land masses with currently tropical climates are lifeless deserts, literally too hot for photosynthesis much of the year
So - presuming we don't trigger a runaway greenhouse effect and turn into a second Venus - what do you think the world will look like a few hundred years from now after everything's been burned? What kind of societies would form in the wake of such utter disaster?
With 10 to 20 billion climate refugees fleeing every coast and every tropical landmass on Earth, do you think a global war for land is inevitable?
How would you imagine keeping the flame of hope alive through such a war?
Or how would you change society so that the worst refugee crisis in human history - now inevitable - brings people together instead of tearing them apart?
Is the long term solarpunk strategy to build a space colony and repopulate the Earth after it burns to ash?
What does a sustainable society look like when all the fossil fuels have been burned and all the damage had been done? And how do we get there?
Well last time the ice caps disappeared, we had 150m higher sea levels and we had tropical rainforests around the poles. So that's about the worst I expect.
And even if not a single plant survives on the surface of the earth due to heat, the planet would still be vastly more habitable than any other planetary body (including moons) in the solar system. Mostly because of the magnetic field, the atmosphere shielding us and abundant water and resources. The gigantic thermal mass of the oceans will keep temperatures survivable for a REALLY long time. Assuming we don't just move to space habitats then. I would expect most people to live in seasteading cities for the lower temperatures and cheap cooling. Probably using solar powered solid state magnetocaloric heat pumps. It would take millions of years for the oceans to boil off, so I wouldn't worry about a Venus scenario. But like, 99.99% life on earth would die out, humanity would be reduced to a couple of tens of millions maybe and we would only be surviving because of our technological competency.
By that point it would be a no brainer to build solar shade satelites at the L1 lagrange point to get temperatures back to normal levels. We could easily do that today if we really wanted. It would just take a couple of percent of current world GDP. It won't fix CO2, but it allows fine grained control over temperatures. IMO this option is way safer than any other geoengineering, because we can turn it off at any time by just turning the satelites by 90°.
You could even do things like making sure every spot on the planet is exactly the same ideal temperature to make it more habitable. But I doubt we would ever do that just for the conservation concerns alone. If we had that technology, we would probably try to revert the planet back to its pre-industrial state.
At the current 4% YoY growth in energy production, we would need to harvest ALL of the energy of the sun within 800-900 years. We will start cooking the planet from our energy prduction alone (as opposed to the GH effect) within the next few hundreds of years. So if growth is to continue, industry and energy production HAS TO move to space sooner or later.
I could easily see us moving most of everything into space some time between 2100 to 2200 and starting to turn Earth into a Garden Planet. We'll run out of space for solar panels and wind turbines some time 120-150 years from today at 4% energy growth rate. Unless we want to pave over the whole planet, then we have a couple more decades of solar... Compound growth is silly like that. You would have to start giant infrastructure to start pumping heat off the planet, like giant radiative cooling towers that glow a bright as the sun (higher temperatures are much more efficient at radiating away heat) or plastering the earth in panels emitting the infrared radiation our atmosphere is almost completely transparent to (think subambient cooling paint).
All of that seems like a giant hassle, so I think energy use on earth will remain low and probably be beamed down from space with solar or fission/fusion satelites instead of being produced on earth. Except for solar cells plastering everthing man-made. I believe the entire earth will be like a giant national park after space industry&energy has outgrown earth.
In my estimation, by 2100 we'll have "solved" the worst technological challeges of climate change and from then on we'll focus on restoring the planet and moving into space.
Why? Because solar technology is still in its infancy and already extremely cheap. With 100s of different energy storage technologies on the near term horizon potentially solving the storage problem in the next 10-20 years, we'll have cheap abundant clean energy. The fact that we don't have cheap abundant is the only reason why climate change is even a problem. If energy was clean and 10x cheaper, you could literally just suck all the CO2 out of the atmosphere we emit in excess. But we don't and that's why it doesn't work currently.
I don't expect drastic decreases to clean energy prices until 2100, but enough that the switch won't be painful, but actually increase overall prosperity. You can already be completely energy self sufficient for around 50k bucks, which is nothing compared to home prices today. And those costs will only come down as the renewable technologies and industries mature. We're basically entering the exponential part of the innovation curve of renewable technoliges. Progress up until now may have been slow, but it will be radical for the next 20 years or so.
I can easily see 90% of cars being replaced by EVs, e-bikes and anything in between. A large part of their fuel will come from solar panels on said vehicles. Short to mid range electric aircraft and drone taxis will become standard. Pretty much all homes will be energy self-sufficient for cheap. Solar panels will enter 30-40% efficiency ranges soon, which means solar EVs become a no brainer, pretty much guaranteeing the average person driving the average driving range will never have to charge them. I expect agriculture to become much more sustsinable, while many degraded areas of land will be rewilded. Both of these are already happening.
There are myriads of technologies to replace CO2 heavy concrete production, not sure how competitive they'll be but at least there's hope.
People will genuinely need less cars because getting around will become much more convenient with increasing walkability, public transport and soon robot taxis.
If cheap energy is sorted out, all the other most CO2 emitting industries will easily decarbonize. E.g. solar + energy storage becomes cheaper than coal, the incentive to build coal power plants will disappear for developing countries.
I'm rambling too much but you get the point, I am pretty optimistic about the future, even in the worst scenarios, I am confident we'll figure it out. After we achieved world wide net zero, the transistion period until the climate has stabilized again will be painful, with ecosystems shifting, farming experiencing issues, hundreds of millions of people potentially having to migrate, but I think we can manage.
Then after that, unless we blow ourselves up, the planet will only become healthier.
My biggest fear really is that fertility rates drop so low, that the world economy collapses, setting decarbonization back by decades. But there are potential technological solutions there as well, like AI.