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[mainiac]

Ocean structures are built by ships. Those things built in docs! Those things that go to port in storms! Venus has neither docks nor ships.

[Il Palazzo]

Mars you need a spacesuit, Venus you need little more than a gas mask and an outer layer, biiiig difference there.

How do you think you're going to deal with 75 degrees Celsius atmosphere, still denser than on Earth = better heat transfer, trying to cook you alive, night or day? You won't be leaving your habitat without a spacesuit either, bub.

There is a range of altitudes where you only need an air supply and protection from acid, I don't think there is a reason to prefer one over another besides whatever works best at the time, and indeed making it so habs could be floated in a range of them, and even change altitudes seems smart, and doable.

What range is that? Certainly not where the atmospheric pressure is around 1 bar.

Lots of things are more worthwhile energy wise in orbit, up in the clouds of Venus you get more sunlight than we do here in orbit, take something which WOULD be too expensive and draw a line under it, with an arrow pointing to the insolation at Venus cloud tops.

Again, at the altitude proposed (50km, 1 bar), the insolation you get is less than 10% higher than what you get in orbit at 1AU - which gives you lower overall energy, because panels in orbit can be permanently angled perpendicular to the incoming light, whereas on Venus, much like on Earth, you only get the max insolation wattage at noon, at equator. You can extend the optimum insolation time and lattitude ranges by angling solar panels with tracking devices, but it only can get you a moderate improvement - no angling will help you at night.
So at best (implausibly), you can get 50% of the listed ~1400W/m^2 insolation, which is pretty much half of what you get in any orbit at 1AU that doesn't pass through Earth's shadow.

[Starver]

One tonne per tonne, all-in. That's superstructure, envelope, inhabitants, machinary, etc.

Where do you get this? So, if I want a warehouse to store a 250000 tons, I need to bring 250000 tons of material to Venus? Don't seem much practical.

No. A warehouse containing 250000 tons (whatever your reason for having one of those, which as yet seems not to habe been decided) weighs 250000 tons plus the weight of the warehouse, which includes the structure and lift-envelope necessary to maintain lift 250000+extras tons (barring a small quibble that I'll skip over).  The extra would not be anything like as much as a quarter of a million tonnes, as it is probably something like a Cloud 9 with a tolerance for up to a quarter of a million tonnes (or tons) if that's what's wanted.

"All-in" was the key phrase.  'Wet weight', not 'dry weight'.

Dismissing the further midunderstandings you made on this point...

(In my head Venus would be like colonizing a gas giant), since the last question answer is a big fat no, then you need to bring everything.

As you would to send a habitat to orbit.

(Mars/Moon-bases, at least at first, would also need the 'tin-cans' lowered from orbit, whether ready assembled on Earth, in LEo or metely fabricated as panels elsewhere, to be bolted together and filled with air once in situ, but what chever way it needs a safe descent option not so much needed (just insertion retros) in orbitals. You can also count on adding regolith/etc on top, saving you sending 'bulk' materials, but untul you set up a local miner/processor/fabricator manufactury you're still delivering the more necessarily designed and machined components.  Venusian Cloud Station is using thick  atmosphere as the equivalent to at least part of the regolith aspect, whilst orbital stations in all locations have to be equipped with all protections thst their host world isn't incidentally providing in some part either by distance (Mars) or magnetically (Earth). Proximity of Venus to the Sun and the more 'accidental' magnetic protection it gets probably requires a tougher orbital station for Venus, albeit not as tough as any surface habitat would have to be, as noted.)

How are you going to manage them to stay in a single place?

Why would you do that?

To find the darn thing? I know structurally talking it will be subjected to less stress as free floating but it doesn't seem very practical for things beyond simply exploration and scientific study. The fact of being free floating doesn't magically do away with the speed of the wind neither.

The ground beneath your feet is travelling at anything up to 1000mph, you know. Yet you don't complain. Why not?

Right, as serene as a ballon flight can be with peaks of 360 km per hour...  And in this scenario... once the planet if densely you'll have the occasional colonies crashing into each other. Nice.

Does your house often collide with your neighbours' houses?  With houses from the next city over? (Maybe it does, if you're somewhere like San Andreas. But not more than once or twice, surely?)

[Starver]

Ocean structures are built by ships. Those things built in docs! Those things that go to port in storms! Venus has neither docks nor ships.

I think I know what you're trying to say, but...  You may have something inverted in there.

[Baffler]

Again, at the altitude proposed (50km, 1 bar), the insolation you get is less than 10% higher than what you get in orbit at 1AU - which gives you lower overall energy, because panels in orbit can be permanently angled perpendicular to the incoming light, whereas on Venus, much like on Earth, you only get the max insolation wattage at noon, at equator. You can extend the optimum insolation time and lattitude ranges by angling solar panels with tracking devices, but it only can get you a moderate improvement - no angling will help you at night.
So at best (implausibly), you can get 50% of the listed ~1400W/m^2 insolation, which is pretty much half of what you get in any orbit at 1AU that doesn't pass through Earth's shadow.

I recall a plan to use orbital (possibly geosynchronous) solar arrays to maximize the utility of solar technology, that would then use microwave power transmission to send what they collect down to a receiving station on Earth. It fell through here because that's a lot of effort of sending something into orbit for not all that much gain, but in this case it would take more effort to safely bring all of that stuff out of orbit. A big dish would also be a lot more compact than a gigantic solar farm too.

[milo christiansen]

The big problem with microwave transmission of power from orbit is that the transmitter is basically a big energy weapon. Better be really careful that it hits the collector!

[Il Palazzo]

Again, at the altitude proposed (50km, 1 bar), the insolation you get is less than 10% higher than what you get in orbit at 1AU - which gives you lower overall energy, because panels in orbit can be permanently angled perpendicular to the incoming light, whereas on Venus, much like on Earth, you only get the max insolation wattage at noon, at equator. You can extend the optimum insolation time and lattitude ranges by angling solar panels with tracking devices, but it only can get you a moderate improvement - no angling will help you at night.
So at best (implausibly), you can get 50% of the listed ~1400W/m^2 insolation, which is pretty much half of what you get in any orbit at 1AU that doesn't pass through Earth's shadow.

I recall a plan to use orbital (possibly geosynchronous) solar arrays to maximize the utility of solar technology, that would then use microwave power transmission to send what they collect down to a receiving station on Earth. It fell through here because that's a lot of effort of sending something into orbit for not all that much gain, but in this case it would take more effort to safely bring all of that stuff out of orbit. A big dish would also be a lot more compact than a gigantic solar farm too.

Orbital solar collectors are a fool's errand. The efficiency of best solar panels is something like 20%, so if you add an intermediary step where you have to transform the collected electricity into radiation to be then again collected by solar panels on the planet, you lose another 4/5ths of the collected energy. This would only be feasible if you collected more than five times as much energy in orbit as you could otherwise, so that the conversion losses are justifiable.

[Max™]

Neat demo: https://www.youtube.com/watch?v=ZlCcn5aoa-U

From this article that goes over the pros and cons of Venus in much more depth: http://www.science20.com/robert_inventor/will_we_build_colonies_that_float_over_venus_like_buckminster_fullers_cloud_nine-127573

They also discuss things like using aerobraking to drop materials on Venus, materials which can be tuned to the correct buoyancy so they simply stop sinking and hang at the right altitudes.

Oh, and my bit about skyelves, I knew it couldn't just be me, after all, Feynman was the one they quoted in the article discussing how trees are built from air, and a pretty effective way of turning "unusable CO2" into living area, building material, food, and so forth.

The micrometeorite and radiation protection at Venus cloud tops is also about the same as it is here on Earth.

The real problem is people think "planetary colony" and jump straight to Mars, with lots of people pushing the idea, not nearly enough discussion about the benefits Venus has over Mars, or fair weighing of the problems with both.

Mars you need a spacesuit, Venus you need little more than a gas mask and an outer layer, biiiig difference there.

How do you think you're going to deal with 75 degrees Celsius atmosphere, still denser than on Earth = better heat transfer, trying to cook you alive, night or day? You won't be leaving your habitat without a spacesuit either, bub.

There is a range of altitudes where you only need an air supply and protection from acid, I don't think there is a reason to prefer one over another besides whatever works best at the time, and indeed making it so habs could be floated in a range of them, and even change altitudes seems smart, and doable.

What range is that? Certainly not where the atmospheric pressure is around 1 bar.

49 to 51 km is what I recall from last time I looked into this.

Lots of things are more worthwhile energy wise in orbit, up in the clouds of Venus you get more sunlight than we do here in orbit, take something which WOULD be too expensive and draw a line under it, with an arrow pointing to the insolation at Venus cloud tops.

Again, at the altitude proposed (50km, 1 bar), the insolation you get is less than 10% higher than what you get in orbit at 1AU - which gives you lower overall energy, because panels in orbit can be permanently angled perpendicular to the incoming light, whereas on Venus, much like on Earth, you only get the max insolation wattage at noon, at equator. You can extend the optimum insolation time and lattitude ranges by angling solar panels with tracking devices, but it only can get you a moderate improvement - no angling will help you at night.
So at best (implausibly), you can get 50% of the listed ~1400W/m^2 insolation, which is pretty much half of what you get in any orbit at 1AU that doesn't pass through Earth's shadow.

1400? Venus gets 2601 W/m^2: http://nssdc.gsfc.nasa.gov/planetary/factsheet/venusfact.html

The clouds themselves are where most of the 0.77 albedo comes from, by design colonies would be above that, and have much more of that sunlight to use.

[MetalSlimeHunt]

Orbital solar collectors are a fool's errand. The efficiency of best solar panels is something like 20%, so if you add an intermediary step where you have to transform the collected electricity into radiation to be then again collected by solar panels on the planet, you lose another 4/5ths of the collected energy. This would only be feasible if you collected more than five times as much energy in orbit as you could otherwise, so that the conversion losses are justifiable.

This is not wholly accurate. The 20% figure people like to throw out is market forces, we have proven cells that are higher. There actually is no hard limit on solar cell efficiency, but the soft limit is ~50%.

I don't necessarily know that orbital solar is unusable, but it relies upon the microwave transmission tech. Solar irradiance in Earth orbit is a continuous 1366.1 W/m2 versus a maximum of ~1000 W/m2 on Earth (nearly always less due to weather, shading, and positioning, but also occasionally higher in ideal conditions). You can definitely collect way, way more energy in orbit due to a lack of non-ideal positioning alone.

If you hit that holy grail of wireless energy transmission, it becomes a good idea. Otherwise, it's still a good idea, but just for orbitals. Not that we shouldn't be expanding our orbitals anyway.

[mainiac]

Not to mention you could actually collect five times as much in orbit...

But really.  Mirrors. Send a concentrated beam to earth. Continuous power for any location on earth you can capture it.

[LordBaal]

No. A warehouse containing 250000 tons (whatever your reason for having one of those, which as yet seems not to habe been decided) weighs 250000 tons plus the weight of the warehouse, which includes the structure and lift-envelope necessary to maintain lift 250000+extras tons (barring a small quibble that I'll skip over).  The extra would not be anything like as much as a quarter of a million tonnes, as it is probably something like a Cloud 9 with a tolerance for up to a quarter of a million tonnes (or tons) if that's what's wanted.

"All-in" was the key phrase.  'Wet weight', not 'dry weight'.

Dismissing the further midunderstandings you made on this point...

Which misunderstandings? About how do you deal with 360 km per hour winds blasting acid? And the huge amount of resources in the long run you are going to carry to Venus? I think those are still things that should be figured out.

(Mars/Moon-bases, at least at first, would also need the 'tin-cans' lowered from orbit, whether ready assembled on Earth, in LEo or metely fabricated as panels elsewhere, to be bolted together and filled with air once in situ, but what chever way it needs a safe descent option not so much needed (just insertion retros) in orbitals. You can also count on adding regolith/etc on top, saving you sending 'bulk' materials, but untul you set up a local miner/processor/fabricator manufactury you're still delivering the more necessarily designed and machined components.  Venusian Cloud Station is using thick  atmosphere as the equivalent to at least part of the regolith aspect, whilst orbital stations in all locations have to be equipped with all protections thst their host world isn't incidentally providing in some part either by distance (Mars) or magnetically (Earth). Proximity of Venus to the Sun and the more 'accidental' magnetic protection it gets probably requires a tougher orbital station for Venus, albeit not as tough as any surface habitat would have to be, as noted.) 

Sure it's already established that radiation would be less an issue in Venus, yet all the other issues remain. Specially the following:

The ground beneath your feet is travelling at anything up to 1000mph, you know. Yet you don't complain. Why not?

It's quite, quite different. We are already in motion with it, not to count that the ground beneath my feet is actually solid.

Does your house often collide with your neighbours' houses?  With houses from the next city over? (Maybe it does, if you're somewhere like San Andreas. But not more than once or twice, surely?)

They would if they were suspended free floating in the atmosphere.

You seem to believe that ballon will magically stay put in the atmosphere, which they will not, they'll be carried away by tornado level winds.

[LordBaal]

From this article that goes over the pros and cons of Venus in much more depth: http://www.science20.com/robert_inventor/will_we_build_colonies_that_float_over_venus_like_buckminster_fullers_cloud_nine-127573

Woa what a interesting reading Max! Thanks for the link. However a certain bias is noted when the guy says that a con with Mars is hard to make self sufficient and will need for parts and supplies from Earth or that we will contaminate Mars with microorganisms when Venus is just the same case I still fail to find hard numbers on how much X volume of gas (be it hydrogen, helium, or breathable air) would lift Y amount of weight at 50 km over the surface of Venus.

The one thing I support 100% is that first we must go to the moon, and from there learn and have a base experience to go anywhere else. Who knows if by then colonies in Venus or Mars would be less technically challenging.

Oh another thing I just tough. While structural failure both on Mars and Venus would mean death, in Mars if you have a suit beforehand (for whatever reason) you might just survive and take a stroll to the next habitat. In Venus it might not mean explosive decompression but it could very well mean a whole habitat plummeting to certain death from which no suit will save you.

[Max™]

He does point out that Venus may have native microbes which would be a problem, but worthy science nonetheless. Definitely interesting read though.

[Starver]

Which misunderstandings? About how do you deal with 360 km per hour winds blasting acid?

By travelling at the same 360km/hr (with afoermentioned materials that can handle the acid).

It's quite, quite different. We are already in motion with it,

...

not to count that the ground beneath my feet is actually solid.

And if you were flying in a hurricane, the ground would be pretty dangerous to encounter.

Does your house often collide with your neighbours' houses?  With houses from the next city over? (Maybe it does, if you're somewhere like San Andreas. But not more than once or twice, surely?)

They would if they were suspended free floating in the atmosphere.

Where the winds from the west hit winds from the east. (Hint: discovering what updraughts and downdraughts there are is a key investigation by the first unmanned balloon-probes looking at viability, as well as just themselves trying to survive whilst studying their other ground-based objectives.

You seem to believe that ballon will magically stay put in the atmosphere, which they will not, they'll be carried away by tornado level winds.

Tornado-level, but not tornado-turbulent, as far as we know. They will stay put (as best as we can tell, so far) within the stream of air, carried along with it in an (it is hypothesised) stable and steady manner.

It is all relative.  Venusian days, for 'air settlers' could be quite different from whatever those 'ground settlers' might experience, as they whizz away below at 360km/h in the other direction, stubbornly proclaiming that they on the (frequently volcanicly refreshing?) surface are the stationary ones.

[Il Palazzo]

Mars you need a spacesuit, Venus you need little more than a gas mask and an outer layer, biiiig difference there.

How do you think you're going to deal with 75 degrees Celsius atmosphere, still denser than on Earth = better heat transfer, trying to cook you alive, night or day? You won't be leaving your habitat without a spacesuit either, bub.

There is a range of altitudes where you only need an air supply and protection from acid, I don't think there is a reason to prefer one over another besides whatever works best at the time, and indeed making it so habs could be floated in a range of them, and even change altitudes seems smart, and doable.

What range is that? Certainly not where the atmospheric pressure is around 1 bar.

49 to 51 km is what I recall from last time I looked into this.

Alright, that's approx 1/2 reduction in pressure over that range. Your habitat would need some major buoyancy control capability to achieve that. Something like making a Dirigible that can fly to Mt Everest while carrying a city.
And if you can't achieve that, then you'll be spending a rather large chunk of collected energy trying to cool down the city so that its inhabitants don't die from heat stroke.

Not saying that it's not possible - just that its yet another major engineering hurdle that makes this all quite a bit less of a no-brainer than you've been painting it.
It's either that magnificent feat of futuristic technology on Vens, or raising a bunch of airtight tents on Mars.

Lots of things are more worthwhile energy wise in orbit, up in the clouds of Venus you get more sunlight than we do here in orbit, take something which WOULD be too expensive and draw a line under it, with an arrow pointing to the insolation at Venus cloud tops.

Again, at the altitude proposed (50km, 1 bar), the insolation you get is less than 10% higher than what you get in orbit at 1AU - which gives you lower overall energy, because panels in orbit can be permanently angled perpendicular to the incoming light, whereas on Venus, much like on Earth, you only get the max insolation wattage at noon, at equator. You can extend the optimum insolation time and lattitude ranges by angling solar panels with tracking devices, but it only can get you a moderate improvement - no angling will help you at night.
So at best (implausibly), you can get 50% of the listed ~1400W/m^2 insolation, which is pretty much half of what you get in any orbit at 1AU that doesn't pass through Earth's shadow.

1400? Venus gets 2601 W/m^2: http://nssdc.gsfc.nasa.gov/planetary/factsheet/venusfact.html

The clouds themselves are where most of the 0.77 albedo comes from, by design colonies would be above that, and have much more of that sunlight to use.

It's 1400 W/m^2 at the proposed 50km altitude. Same as on Earth's surface you get 1000 W/m^2 (max) instead of the 1400 in orbit. See the NASA study linked earlier.