The Poobahs of Glasgow have spoken.
This is one of the reasons I'm heavy into space stocks and space development in general. From my perspective, the dangers of climate change are real, BUT we're well past the point where a strictly Earth-based humanity has the ability and (more importantly) will to reverse course. In short, humanity is in the process of outgrowing this planet, and absent some MAJOR catastrophe that reorders human civilization globally, we won't lift ourselves onto that next step that the climate advocates keep preaching at us, as (you rightly point out), we're not collectively willing to stabilize our population levels (witness the angst around developed nations not having enough kids) and consign others back into subsistence-levels of living that would reduce their carbon footprints (nevermind voluntarily adopting a subsistence lifestyle OURSELVES).
Sci-fi writer Charles Stross (a fellow who thinks and writes heavily on these topics) paints a picture that seems to become more plausible every day:
"So. What kind of vertically integrated business synergy could Musk be planning to exploit to cover the roll-out costs of Starship?"
"Musk owns Tesla Energy. And I think he's going to turn a profit on Starship by using it to launch Space based solar power satellites. By my back of the envelope calculation, a Starship can put roughly 5-10MW of space-rate photovoltaic cells into orbit in one shot. ROSA—Roll Out Solar Arrays now installed on the ISS are ridiculously light by historic standards, and flexible: they can be rolled up for launch, then unrolled on orbit. Current ROSA panels have a mass of 325kg and three pairs provide 120kW of power to the ISS: 2 tonnes for 120KW suggests that a 100 tonne Starship payload could produce 6MW using current generation panels, and I suspect a lot of that weight is structural overhead. The PV material used in ROSA reportedly weighs a mere 50 grams per square metre, comparable to lightweight laser printer paper, so a payload of pure PV material could have an area of up to 20 million square metres. At 100 watts of usable sunlight per square metre at Earth's orbit, that translates to 2GW. So Starship is definitely getting into the payload ball-park we'd need to make orbital SBSP stations practical. 1970s proposals foundered on the costs of the Space Shuttle, which was billed as offering $300/lb launch costs (a sad and pathetic joke), but Musk is selling Starship as a $2M/launch system, which works out at $20/kg."
"So: disruptive launch system meets disruptive power technology, and if Tesla Energy isn't currently brainstorming how to build lightweight space-rated PV sheeting in gigawatt-up quantities I'll eat my hat."
And Jeff Bezos' vision:
"The billionaire tech entrepreneur also laid out a vision for space commercialization that stretches out for hundreds of years, leading to an era when millions of people would be living and working in space."
"'I think space is chock full of resources,' Bezos told reporters. 'This is all my view, and I’ll be dead before I’m proved wrong, so it’s a very safe prediction to make. But my view is that there will be a ‘Great Inversion.''"
"Today, huge industrial complexes on Earth build components that are sent into space, at a cost of thousands of dollars per pound. Bezos foresees an inversion in that flow of goods. 'We’ll make the microprocessors in space, and then we’ll send the little tiny bits to Earth,' Bezos said."
"In the long term, Blue Origin could set the stage for moving heavy industries completely off Earth, leaving our planet zoned strictly for 'residential and light industrial' use."
"The trends pushing in that direction include the need for space-based energy generation to fill industrial demands, the need to reduce the pollution caused by industrial activity, the falling cost of access to space and the eventual ability to use asteroids and other space resources."
So, to me - it seems like we're on the edge of a VERY important inflection point, likely more significant than the haydrocarbon revolution that occurred almost two hundred years ago that's powered mankind for the last two centuries. Renewables are part of that equation, but given that most renewables (not geothermal) ultimately derive their electricity-generation ability from raw solar power (directly for PV systems, indirectly for wind-based systems) AND the energy loss solar power suffers before it gets to a place where renewable technologies can exploit it, this indicates to me that there's great progress to be made by getting the bulk of our power generation outside the atmosphere and soak up those sun rays as directly as possible.
Looking it it from a technology development perspective, we're on the cusp of it being affordable to begin building and testing prototypes for the types of systems that Stross identifies, and we just need to figure out safe and effective ways to beaming the energy we're collecting in orbit down to Earth where it can be used. In terms of manufacturing, the first company that manages to identify and capture a metal-rich asteroid will bootstrap an industrial economy that makes our current output look like a cute effort from a handful of artisans. (And instead of bringing the asteroid to Earth to mine, it may make sense to send the refinery and factory to the asteroid as the mass of the former will be much smaller than the latter.)
In terms of climate change, I'm VERY bullish that we have the means to manage Earth's and make this planet a garden - I just hope that we don't run out terrestrial petrochemicals that we use for rocket fuel before we find a way to synthesize it independently of long-extinct megafauna and other prehistoric biomass.