Underwater City Thread:

>Hampture
thanks, hadn't seen this guys vids before

>electrolysis to get oxygen and hydrogen
>Use hydrogen for part of your energy needs to recoup some losses from electrolysis
yeah thats what i was thinking, BUT, how would you change the ox/hyd back into water? reverse electrolysis doesn;t exist does it?

Electrolysis like this on this big of a scale would **eventually** use all the water

>Energy could be made via waves using tethered floats. Sterling Engines can use the temperature difference between the waste heat and the water outside to create power as well.
GREAT ideas also

also, I was thinking that natural daylight could be sent down into the roofs via fibre optic cables to the surface and a sequence of mirrors

it's probably only good for tourism

People defending fish rights

>ITT you tell me why this can't be done.
>DO NOT SAY UNECONOMICAL / TOO EXPENSIVE
Other than the fact it's unreasonably expensive, and has little purpose, it's obviously possible.
Maybe a small research outpost could be justified, but that's it.

>Couldn't large pipes extending to the water surface just be created to allow flow of air?
Yes. You'd probably want to keep the pressure inside the same as outside, so you'd need pumps to compress the air.

>Hampture
Holy shit, that's amazing

>Just use electrolysis to get oxygen and hydrogen.
That's possible, but very energy intensive.

>Use hydrogen for part of your energy needs to recoup some losses from electrolysis.
What would you react the hydrogen with? The only thing available would be the oxygen you just made, and that would defeat the point of running the electrolysis in the first place.

>Energy could be made via waves using tethered floats.
Another option, based on things that have actually been built, would be to have a raft or barge floating above and tethered to the habitat. The raft could compress air and pump it down to the habitat, and it could use solar panels and diesel backup generators to supply the habitat with power.

>Sterling Engines can use the temperature difference between the waste heat and the water outside to create power as well.
The temperature difference would be far to small to make useful amounts of power.

>reverse electrolysis doesn't exist does it?
Fuel cells.

>Electrolysis like this on this big of a scale would **eventually** use all the water
No.

>also, I was thinking that natural daylight could be sent down into the roofs via fibre optic cables to the surface and a sequence of mirrors
That sounds like a hell of a project to maintain underwater. LEDs are far cheaper and simpler, and don't consume much power.

>Yes. You'd probably want to keep the pressure inside the same as outside, so you'd need pumps to compress the air.
ah okay

>What would you react the hydrogen with? The only thing available would be the oxygen you just made, and that would defeat the point of running the electrolysis in the first place.
hmm... could this be improved upon somehow, what would you react it with?

>That's possible, but very energy intensive.
What would be the most effective way for energy?
electrolysis, solar, sterling engines, generic hydropower, tethered floats/waves, nuclear fisson, nuclear fusion using hydrogen (when/if discovered), conventional coal/oil, wind using floating turbines or some shit, possibly some device that uses water pressure at a depth to create energy?

>The temperature difference would be far to small to make useful amounts of power.
true

>Fuel cells
>No.
true thanks

>That sounds like a hell of a project to maintain underwater. LEDs are far cheaper and simpler, and don't consume much power.
Yeah LEDs would be better for those reasons, but if people only got LED light they'd lost their minds after a month. I just mean maybe one cable for every "black" of land (sea), then use glass/mirrors to "split" and "boost" the light (would that even work or would splitting up the light cause it to become less intense (i know imperfect mirrors would make it less intense))

>hmm... could this be improved upon somehow, what would you react it with?
Not really. The hydrogen is basically waste.

>Yeah LEDs would be better for those reasons, but if people only got LED light they'd lost their minds after a month.
Maybe. I still think re-creating sunlight is vastly more practical then trying to pipe it. Besides, I think the "losing their mind" is more a claustrophobia thing that a lighting problem, and that can be addressed with windows.

>What would be the most effective way for energy?
That depends on how much energy you need, how permanent the facility is, and how much money you have.

>electrolysis
Electrolysis consumes electricity, it doesn't produce it.

>solar
If you don't need masses of energy, and you have a raft, then solar is probably a good choice.

>sterling engines
Stirling engines need a heat source to run, which you probably won't have.

>generic hydropower
??

>tethered floats/waves
They don't produce much power, and they need LOTS of maintenance.

>nuclear fisson
Expensive as fuck.
If we're talking about an actual underwater city then maybe that would make sense, but for anything smaller a reactor would be unaffordable.

>nuclear fusion
One day.

>conventional coal/oil
Require air to burn.

>wind using floating turbines or some shit
Maybe. You'd need a good site.

>possibly some device that uses water pressure at a depth to create energy?
Not possible. You'd need to flow water down to somewhere lower, and I doubt you'll find a lake full of air at the bottom of the ocean.

>Not really. The hydrogen is basically waste.
wouldnt be if we had fusion

>Maybe. I still think re-creating sunlight is vastly more practical then trying to pipe it. Besides, I think the "losing their mind" is more a claustrophobia thing that a lighting problem, and that can be addressed with windows.
windows, thats interesting because you wouldnt be able to see any light out the windows at big depths would you, but you could put lights inside the windows wo have "lit up water" in the windows, yeah?

>Electrolysis consumes electricity, it doesn't produce it.
of course

>Not possible. You'd need to flow water down to somewhere lower, and I doubt you'll find a lake full of air at the bottom of the ocean.
how about big cylinder tower stacks with an open top that go all the way to the surface, when water pours it it passes paddle wheels (and by gravity) and produces elec using generators? this could also be used to provide air and light

>What would you react the hydrogen with?

With the oxygen you just made. It'd onyl be an on-demand use, not like some energy generator thing. More like when you need to use an HHO torch or something similar. Storing it short term would be fine. Since you'd be making it all the time, there's no need for expensive storage to prevent leakage from the hydrogen tanks.

The cool thing about HHO torches is that they work submerged underwater if they are designed correctly for the pressure flow.

>raft could compress air and pump it down to the habitat,

The wave electric generator could just skip making electric and be run specifically as a mechanical-only pump using waves to pump it. Thus skipping all the electric stuff needed. It'd be like a wind turbine that direct drives a water pump, only using waves for pumping air.

> temperature difference would be far to small to make useful amounts of power.

Not really. Underwater temperatures are pretty cold. Sterling Engines only need a small temerpature difference to work. Also, you'd not be using small S.engines. You'd be using one that are quiet large and have lots of surface area. This means even less temperature difference are needed (though it will have quite large temp differences in this use.)

Like 4000-4500m deep you have 3-4C and inside the city is 23C, but your waste heat from engines, electric generation, etc would be far higher temps. Just temp from 3C to 23C is more than enough to run a large surface area Sterling Engine.

The problem is, "How much waste heat will there actually be when you need to heat the city?" I'm sure aerogel insulation panels and blankets would do a great job at helping maintain indoor temps so that there would actually be waste heat to spare.

OP what's the point of this thread supposed to be.

You can set your language to English on your PC if you are having trouble reading the OP text for some reason. (hope you can read this and understand)

>air pipes going to the surface

I think those should only be used in an emergency and not be relied on exclusively.

Level 1: City-generated oxygen + scrubbers
Level 2: Surface pipes with backup power for compressors/pumps or wave-run compressors/pumps
Level 3: SCUBA gear, last measure of security incase of total failure of all other air/oxygen systems.

For CO2 scrubbing, you can use sea water scrubbing. For oxygen generation and partial CO2 scrubbing you can use algae. However, you need light for algae to grow properly. Thus, you'd need some sort of surface or near-surface algae farm. Otherwise, you end up using energy for light down below which might be ok depending on the robustness of your power generation system.

Personally, I think anything leaving the city on a tether or pipe should be something only used in emergencies and the city should rely on doing everything on the sea floor. Otherwise, it sorta defeats the purpose of being underwater in the first place, if only by principle.

For energy generation, sea floor Hydrothermal vents could be utilized for power generation. That of course depends on whether or not you'd actually be allowed to do that due to the fact each one has a very unique and special ecosystem that only exists around the vent itself. The best solution would be to find a brand new vent that recently formed and doesn't have a micro ecology it is supporting yet. Meaning the kind of life forms living around it are found most everywhere and not only at a vent.

>full of air at the bottom of the ocean.
>how about big cylinder tower stacks with an open top that go all the way to the surface, when water pours it it passes paddle wheels
Reading your posts makes me lose faith in humanity.

Kill yourself my man.

wtf I thought this was a good idea??

why wouldntit work?

Ur retarded of course it could be done but who wants to dump billions into an underwater city when there is literally no point, there is no economic value to be had, so it won't happen

you don't need to go down to hydro vents, you can just use the same machinery as oil rigs to find a sub-oceanic heat source

What about a city in the sky like for example [spoiler/]Bioshock Infinite[spoiler]?

very funny now fuck off

marine algal growth and salt corrosion is absolutely rampant

>be me, be a diver
>sometimes have to clean the bottom of a big ship with scuba gear on
>after like 6 months that shit is covered in barnacles and algae
>you literally have to take the whole boat out of the water to get it all off properly
>special copper based paint inhibits growth
>that shit still gets totally covered in like a year

apart from that, the ocean literally wants to eat manmade structures. Its amazing we can float around on the surface for months at a time; living down there is out of the question

It's too expensive ;^)

come on Veeky Forums if they can do it surely you can :^)

Sounds like you have a cool job user.

very funny now fuck off

That isn't entirely a valid use though. It is better to utilize a known and existing source than trying to drill down and hope you get it right. However, since all this tech needs to be developed, developing such tech for hot geothermal wouldn't be much more of a stretch.

Use vitreous enamel on all non-glass parts exposed to sea water of the city. It will last decades in comparison to normal ship hulls. It'd most likely need to be a tile based system to prevent warping and spalling from pressure changes.

Anyone willing, can read up more about it,

porcelainenamel.com/503_-_Corrosion_Resistance/

I've got the perfect plan bros.

We build simple, powerful batteries using the carbonic acid and electrolyte rich seawater to power our city. Think about how an electrochemical cell works. If we can find a way, using large metallic electrodes to create a reduction potential, we've got a bountiful energy source at our disposal. And we'll de-acidify the ocean and give pop-scientists something else to worry about. "Ocean alkalinity" has a nice ring to it.

it is cool senpai. once there was a noob watchman on duty and they started up the boat while it was on top of me

>mfw nearly sucked into a giant propellor

i'm liking the vitreous enamel, but marine growth is going to block exhaust pipes etc. within a matter of weeks

also the issue of atmospheric pressure;
are we going to build structures above water, coat them in antifoul and vitreous enamel and then drop them 30 + metres under the water ?

If you take a plastic bottle to just 10m depth underwater you will quickly see why this poses a problem.

Also, enjoy not seeing the full spectrum of colours anymore; spectrums like red, yellow, orange are invisible at about 20 - 30 + metres depth

en.wikipedia.org/wiki/Underwater_habitat

Read up before asking please. Underwater technology isn't new to science. You don't need to reinvent the wheel.

bump

Why would this actually not work though?

The cylinders would just fill with water.

not if the seawater went into some sort of desalination plant, then got turned into drinking water, then pumped out through drains, sinks, etc into another cleaning filter then back into the sea

at the bottom of the "tower stack that went to the surface", that is

>then back into the sea
You are gonna end up spending equal amount of energy

hmm...

but pumping it out into the ocean would be way less energy than it falling 50-300 metres in the tower through paddlewheels would it??

No. If it took less energy it would be perpetual motion machine and break conservation of energy and even you should know that that is stupid

but isn't it because it falls that the potential energy it had gets converted into kinetic/electrical energy (in paddlewheel) and that doesnt get reconverted because it is down at the lower height now (potential energy) and because it is pumped out lower in the ocean it can work this way?

Please respond. Thought OP was a bit of a brainlet but now it seems like this would work. Would the pressure be so much that the energy required to pump it out would still be higher than the energy gained?

Yeah that's right. Due to the pressure down there, the energy input required to pump it back into the ocean would cancel out any net energy gain. Still an entertaining thought though.

Sorry to be such a buzzkill. But you just can't cheat the law of conservation of energy haha

Source: majored in fluid mechanics a few years ago

This.

The only way you can "cheat" shit energy laws is to hijack other natural systems to input power for you so you don't have to do it. Like biogas methane generation. The microbes are the workhorses that make the system put out more energy than humans need to put into it. But, without the microbes, it'd not be worth attempting.

Biogass methane generation would also be a good use of waste products to gain energy in a self-contained city like that. You get high-nitrogen fertilizer and methane from it.

derelict underwater ballroom

We can build underwater skyscrapers with today's technology, but unless you're really into brutalist architecture, no one will want to live in them.

Pic related is the interior of one of Troll A platform's concrete support columns. These columns go down to 303 meters below sea level. Overall the Troll A platform is just about as tall as the Petronas Towers.
en.wikipedia.org/wiki/Troll_A_platform

Unfortunately, that's where the similarities with skycrapers end. The concrete walls of these columns are about 1 meter thick. Windows are next too impossible here. Certainly nothing like 'LOL BIOSHOCK'. We could maybe manage small porthole type windows, although the thickness does make things rather difficult. So any windows will be expensive and would have to be minimized.

Which would make living in an underwater skyscraper built into something like the Troll A platform about as fun as living in a windowless apartment. And who really wants to do that?

In other words, it's uneconomical/too expensive. :^)

>unless you're really into brutalist architecture

You don't have to see the walls, They can be "dressed up" if needed.

Too bad the Conshelf stuff never caught on.

What's the point of conshelf?

cousteau.org/technology/conshelf-i-ii-iii/

>cousteau.org/technology/conshelf-i-ii-iii/
So it was to see if humans could live underwater.

that reminds me of that round anomaly in the Baltic sea 4 years ago. I don't think anything interesting developed from that.

Yup. Now fast forward 50 years and the only thing we really use that tech for is prepping astronauts for space and some diver training.

Wasn't that just a nicely shaped rock?

Bestiality aside, I liked the concept of the semi submerged dolphin friendly house.

telegraph.co.uk/culture/film/10860676/The-woman-who-lived-in-sin-with-a-dolphin.html

Makes sense. There is no need for such things.

Is everyone here underage or what?

At higher pressures air is going to be a hell of a lot less oxidizing because of substantially more buffer gasses.

Sounds too Disney to be realistic.

what happened?

pressed the lighter so the gas comes out, it filled up the closed car and then he lit it on fire.

It's stupid. How's that for an answer?

aquaman?

>Just use electrolysis to get oxygen and hydrogen
lol, see Op? This idea is stupid.

Who the hell wants to live in that shit hole, looks like a nigger ghetto.

Three kids somewhere in Saudi Arabia were sniffing butane in a car, the dude in the backseat though it'd be funny to pull out a lighter and ignite it.

But the car isn't loaded with gas??? Does that always happen in a closed environment? Did the gas from the lighter leak and filled up the close car?

Oh, that explains it. That's pretty dumb then, what did they expect would happen? Tsk tsk.