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Saudi Crown Prince unveils plans for $500bn structure to house 9M people

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Re: Saudi Crown Prince unveils plans for $500bn structure to house 9M people

#231

Earlier quoted context omitted.

Building something like this in a democratic society is probably impossible. The reason is that there would be massive opposition to this and rhetorically powerful claims that the trillions of dollars this would cost in a Western society could be put to better use. Even if, by some Deus ex machina, one administration managed to get this project going, the next to come into power would likely can it. Space is a perfec…

> There's no technical reason we haven't established footholds on Mars and even the Moon Lack of atmosphere, dangerous voyage, radiation, lack of easily available nutrients, dangerous weather, different gravity, likely one way voyages and of course the everpresent lack of any particular economic incentive to do so

The amount of material resources in space are breathtaking. Asteroid mining has the potential of delivering multiples of the amount of elements we've mined for our entire history in single asteroids. That alone could sustain a space economy.

There also isn't our massive gravity well. If you have materials (see point 1) it is easier to build large installations. We should be able to build GIGANTIC underground habitats in the moon.

There was also the powers-of-ten energy use as we climb Kardashev levels. That only happens with space settlement.

The other economic fact is that we have too many people for the Earth to sustain already AT THE CONSUMPTION THEY WANT. Sure we can impose a resource restriction by fiat (communism/authoritarian) or availability/poverty (capitalism), take your pick.

Space will come more easily with cybernetics. In a hundred years humans may be very very very different. But footholds are worthwhile.

But ultimately your comment harkens to the lack of vision of humanity, mostly I view it as a sign of increased control by the leisure elite over the world. They control the money and politics, and all they want are status and enjoyment, and the rest of the world to support them.

We have a thin margin for species survival right now. It's kind of like how when the tipping point for global warming in the 1990s was happening, everyone in America bought SUVs.

Sad.

Re: Saudi Crown Prince unveils plans for $500bn structure to house 9M people

#232
post #10

At 56k per person for both living and working space plus associated infrastructure, 500bn doesn’t seem like nearly enough.

Probably not, but I also wouldn't presume Western economics. Saudi has supply to unlimited low-cost labor from Africa. Things get built with virtually no labor costs relative to the West. I think I would be miserable without a yard, though. I don't think I want to spend my life inside of a manufactured block.

I still don't think it's close to enough.

At 170km long, 200m wide, 500m tall, the volume is 17,000,000,000 m^3. They're planning on spending just $29.41 per m^3.

Just trying to get a point of reference, the Burj Rafal is 308m tall with a 20,000 m^2 plot and cost $320M. Running the numbers they spent $520/m^3 on that, and it's shorter (I presume added height increases costs and complexity). Infrastructure was also likely already provided by the city, and not counted in that budget.

Honestly, I think even material costs are at least an order of magnitude higher than they want. The scope of this boggles the mind. They need 170M m^2 of mirrored glass just to cover the outside of this.

That's not even touching the foundation and reinforcement it takes to support a 170km long, 500m tall wall that's going to bear all the force of wind coming off the ocean. Wind speeds seem to peak at about 16m/s, so the force on a 1m section of the wall would be ~78 kN. That's roughly the force of 3 Tesla Model S' at full acceleration (but spread vertically). The force across the entire wall would be equal to ~381 Saturn V rockets at lift-off, or about 23 times the force that sunlight exerts on the entire Earth.

Re: Saudi Crown Prince unveils plans for $500bn structure to house 9M people

#233
post #140
post #125

I doubt it will get built, but they really have people who understand the fundamental concepts behind Arcology. Honestly I'm surprised at how many parts of the design are well thought-out and well adapted to the desert environment. Sunlight from the sides, but not so much that it overheats the city. Heat escapes up. 5-minute walkable neighborhoods. The proximity to services of cities combined with the roominess of su…

The dystopian side is the lack of squares to protest on ;) In all seriousness though, the project does look very realistic and I can't find any major flaw with it except that the glass wall will need to be a triple-mirror which is ridiculously expensive. The other unknown is how an idealized architecture like this stacks against real-life humans who don't care to maintain anything if they're not paid for it. I do hop…

I posted down below as well, but I think wind is going to be a big issue for them. A 170km long, 500m tall wall is about the least aerodynamic thing I can think of. I would anticipate that wind issues will be substantial.

My napkin math said that if peak wind speeds hit it dead on, the wind will impart a force of 156N/m^2. A 1 meter wide slice will have to absorb roughly the force of 3 Tesla Model S' pushing on it at full throttle. Across the entire wall, the force is roughly equal to that generated by 381 Saturn V rockets at lift-off.

The other problem is price; they're almost certainly off by at least a couple orders of magnitude. The Burj Rafal is 308m tall with a 20,000m^2 base, and cost $320m, which comes out to $520/m^3. $500bn for this comes out to $29.41/m^3. That price for the Burj Rafal probably doesn't include public infrastructure (electricity generation, water cleaning, sewers, etc), and Neom will be way too big to piggyback on an existing system.

It's a neat idea, I agree I hope they build it, but I hope they do so cautiously. Build a kilometer or three and then revisit the design and costs. Starting with a 170km version of it almost assures that it never actually gets finished.

Re: Saudi Crown Prince unveils plans for $500bn structure to house 9M people

#234
post #155

Earlier quoted context omitted.

>5-minute walkable neighborhoods. The proximity to services of cities combined with the roominess of suburbs. At least in theory it's the perfect place to live. The problem with 175 km of continuous "subway" is that you probably don't want to walk more than 2.5 km to the train (if that, it's Arabian hot) so you have 35 stops (5 km apart) along the line at a minimum — with a blistering acceleration of g = 10 m/s^2 you…

imagine train lines that stop at prime number stations. so line 2 would stop at station 2,4,6 like 3 would stop at 3,6,9. if you want to get to station 10 you could take line 11 directly to station 11 and then line 1 back. alternatively, you could use an app to calculate the best route based on when you arrived

That probably depends on how many rails and when trains can cross onto other rails. I.e. a basic flow is all trains go one direction on one rail, and they all go backwards on the other. You can use the "wrong direction" rail to pass another train, but only if there's no oncoming train. Waiting for a train to go through so you can cross is effectively the same as stopping at a station.

The answer is to have more rails, but that takes more space, and I'm not sure how much space they're dedicating to the rail system.

Rail scheduling is fascinating; it does make me curious how fast they can make this system in a real world environment.

Re: Saudi Crown Prince unveils plans for $500bn structure to house 9M people

#235

A lot of skepticism in this thread, even some form of jealousy It's better than the soviet union like buildings they are promoting everywhere in the world, including in the US We need to optimize cities as much as possible, that's for sure, this project is a step in the right direction

I just like Saudi Arabia for their treatment of migrant workers and the Kafala system. The treatment of women doesn't help either.

Re: Saudi Crown Prince unveils plans for $500bn structure to house 9M people

#236

Earlier quoted context omitted.

A circle is harder to build and has more issues regarding sunlight. The sun hitting the building(s) is both a benefit (solar cells) and a problem (heat generation) at the same time. A linear structure will get a much more even energy distribution than a circle. Also one of the goals of the project is to reduce the energy needs of the population by making ways shorter. If you spread a city out on a circle, you got a m…

Also, a circle, you couldn't expand indefinitely

Wait, you can expand a line indefinitely? How? Eventually you will hit water or a mountain.

Re: Saudi Crown Prince unveils plans for $500bn structure to house 9M people

#237

Earlier quoted context omitted.

A lot of big city metro networks look like grids in the city center, or effectively function as such. Farther out the grid is plugged in by bus.

Can you provide an example of a city with a grid-like metro? I know many grid like cities. I cannot think of any grid like metros.

Grid like comes with a caveat. Most grids are only in city center (so that lines can connect to every other line in the city with most demand), and subways are not often grids but rather interlocking L shapes and curves depending on which radial direction out of city center got to have a subway first (but usually you can still see distinct gridlike patterns). And then there's geographic impediments like where streets and parks are.

Beijing is a grid: https://upload.wikimedia.org/wikipedia/commons/0/07/Beijing_...

Shanghai is a grid: https://en.wikipedia.org/wiki/Shanghai_Metro#/media/File:Sha...

Tokyo is grid-like east and south of the Imperial Palace: https://i0.wp.com/transitmap.net/wp-content/uploads/2020/11/...

Taipei has a grid: https://english.metro.taipei/cp.aspx?n=1BE0AF76C79F9A38

The gridded portion of Manhattan has a grid between 14th St and Central Park: https://english.metro.taipei/cp.aspx?n=1BE0AF76C79F9A38. Buses fill out the grid in outer areas like the Bronx: https://new.mta.info/map/5366

Paris is gridded about as much as it can be due to the non-grid road layout: https://www.ratp.fr/sites/default/files/plans-lignes/Plans-e...

Berlin is gridlike: https://sbahn.berlin/en/route-map/

Re: Saudi Crown Prince unveils plans for $500bn structure to house 9M people

#238

Earlier quoted context omitted.

Just because the Star Trek universe had WWIII doesn’t mean we have to. I would like to live in Star Trek via the path of least suffering, but whatever path, it is the future I wish for generations to come regardless the struggle I personally have to endure. To wish the current system upon children and children’s children is selfish and cruel beyond imagination. If people wanted, we could all wake up tomorrow and begi…

That's easy to say if the bombs are not falling on your head. And I'm also not so sure that the current system can save itself from within. Evolution has navigated us into a dead by favouring immediate benefits over long term ones, now that our influence on the planet transcends our own lifetime. Getting out of that will require something pretty radical.

It’s easy to think of things as a dead end but the optimization landscape is huge, so there is usually some options open. Take say retirement incomes, love it or hate it Social Security was supposed to provide a minimal benefit for elderly workers who already had the option for private savings.

But soon enough we added Medicare, 401k, IRA, etc as independent systems for similar reasons. While I doubt anyone would have ever created the current system from scratch, it’s just one of seemingly endless possibilities.

Re: Saudi Crown Prince unveils plans for $500bn structure to house 9M people

#239

Has nobody considered the possibility of such vast, shiny external reflector walls absolutely, very literally roasting the surrounding landscape when struck by the already ferocious Arabian sun? How would a person even survive openly coming close to this fascinating monstrosity from either side at certain times of the day? I remember a story about sunlight reflections bouncing from the "Walkie Talkie" Building in Lon…

You are missing the central point of the Walkie-Talkie and Disney-Concert-Hall controversies. These are Frank-Gehry(-style) buildings, and in those roughly half of all surfaces is a concave and half is a convex mirror. THIS concentration to one point is what turns the summer sun into death rays. Reflected sun, by definition, has a little less energy than direct sun. So, given the mirror walls are straight, as the des…

You're grossly understating just how brutal it would be. While you're right about how concave mirror surfaces truly create lethal concentrations of energy, this vast reflective surface would still unbearably heat the land next to it at certain times of day. 200% of Arabian Peninsula levels of solar heat as only "uncomfortable"? You've got to be kidding.

Re: Saudi Crown Prince unveils plans for $500bn structure to house 9M people

#240
post #155

Earlier quoted context omitted.

>5-minute walkable neighborhoods. The proximity to services of cities combined with the roominess of suburbs. At least in theory it's the perfect place to live. The problem with 175 km of continuous "subway" is that you probably don't want to walk more than 2.5 km to the train (if that, it's Arabian hot) so you have 35 stops (5 km apart) along the line at a minimum — with a blistering acceleration of g = 10 m/s^2 you…

The video says it's 20 minutes end to end, somehow.

The numbers in my post have some significant errors — I mashed it in just before my plane was taking off — but the argument is one I have seen carried out more carefully elsewhere.

175 km in 20 minutes would be roughly the top speed of the fastest train ever built. I'm doubting that.

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