Hypx

It could mirror the economic stagnation of Japan that begun in the 1990s. Very similar set of circumstances.

Yes, that's the point. It's far beyond the actual city of Tokyo in terms of construction difficulty and scale. But it doesn't need any new technologies to be invented to be doable. Just the ability to build on that scale.

This is sci-fi stuff. No one is seriously saying we could build this anytime soon. It will require a radical advancement in space travel capability. But the interesting part of this is that it doesn’t any new technology. It needs only the technology that we currently have, just scaled up massively.

As it is an O’Neill cylinder, the raw material needs will be truly huge. We’re literally building a city on the scale of Tokyo but in space. So we are just assuming that someday, we can move around that amount of stuff in space.

The cheapest materials would be what can be acquired in space without having to launch from Earth. As a result, you're going to want to build your O'Neill cylinder out of some combination of iron, aluminum, titanium, and silicon dioxide.

The last of which might be particularly useful, as it is the main ingredient of fiberglass while also being the most common substance on Moon and asteroids. As a result, you probably want to build your cylinder primarily out of fiberglass. You can get pretty decently sized cylinders, as fiberglass has a higher strength-to-weight ratio than steel. Apparently, 24km diameter is a viable figure. Scale up length the same way, and you'll get 96km. So a 24km x 96km O'Neill cylinder made out of fiberglass.

That would be about 7238 km^2 of usable surface area. Half that to 3619 km^2 to make room for windows (as originally envisioned by O'Neill), and assuming a density comparable to New York City (about 11,300 people/km^2), you'll get around 40 million people. Or about the population of Tokyo.

That's seems plenty for any sensible space colonization strategy we might adopt in the future. And what's best is that you don't really need any fancy technology. Just use solar power to power mass drivers and deliver raw materials from the moon or asteroid via electricity. And it won't be any special materials either. Raw regolith can be made into fiberglass, so cost can be kept surprisingly low. The only question is scaling it all up, which may unfortunately be too expensive or will take a very long time to happen. Ultimately, this is still sci-fi, albeit on the hard side of it, since no fancy new technology is require.

You’re better off spending it on stuff like mass transit and the like. It won’t just all disappear at some point in the future.

You won't be saying that once the market crashes. You'll realize that there are much better ways of spending that money. Like far more practical emissions reducing solutions.

Not really. It's mainly about gaining market dominance on a technology they think is the future. They'll build them right next to the massive coal plant alongside a million other things they're subsidizing.

It's the result of massive subsidies. When they stop, this market will crash like a house of cards.

IOW, this is right-wing propaganda. And given her skin-color, you can add racism to that mix too.

Blogs are a good idea. We should go back to them instead of being dependent on social media.

That's just BS. The longevity of everything is comparable to that of natural gas related equipment. It will be much cheaper than massively expanding the grid and build batteries for everything. Not to mention that you can reuse much of the natural gas infrastructure.

Green hydrogen is growing exponentially in the same way wind and solar grew. The upside of something that isn't dependent on finite fossil fuels. It will eventually be available in vast quantities and at a very low price.

Those are wildly exaggerated. The main limitation is that society hasn't invested enough in hydrogen infrastructure. At least not yet. The problems would quickly go away if we did.

You also forget that we've poured many billions of dollars into electrification and battery production. That amount of investment would have solved a lot of those limitations.

As green hydrogen is made from water, there is basically no battery chemistry that can rival it in terms of availability. It is basically the best energy storage mechanism of this type already. Saying that batteries can get better is just misdirection. Also, you can have plug-in hydrogen cars too. The natural path is probably hybrids -> PHEVs -> plug-in FCEVs. Pure BEVs are in many ways a side-trip.