Writing Science Fiction Novel about living above Venus in the near Future! Need help with Science!

[Andrew Zachary Foreman]

Hey guys! I am new to the kerbal community and really hoping y'all can help me out! I am writing a novel about life among the clouds of Venus and I need help figuring out some basic science about how people would do it. I have done quite a bit of research online but there still remains a number of questions I can't seem to answer. They are as follows:

1. What is the range of atmospheric pressure above Venus in the range of 20-50 Km? I understand that near the top would be about 1 bar. 

2. What would the temperature range be like in this 20-50 km area? I have heard wildly different estimates. Some say that towards the bottom of this 20 km the temperature would be near tropical climate and that higher up, close to the 50 km, the temp would be closer to sub-polar. Then again, others have said that even near the top of this range the temp would be well above 150 Fahrenheit. This would imply that it would be even warmer the lower you go. 

3. My third question should be fairly easy to clear up. The habitat design in my book mimics airships. The things I need to know are how much mass can a given quantity of air lift, and what would be the pros and cons of helium, hydrogen, and earth air. Should there be any other gases I should consider?

4. The highest mountain on Venus is about 11 km as I understand. Would it be practical to mine resources from mountain tops to fuel an expanding economy? If it wouldn't, what other options would there be? My understanding is that asteroids would be too far away to be practical and that the atmosphere wouldn't have enough elements to meet all of the expected needs.

5. How hard would it be to get water from sulfuric acid?

Are there any other things I need to know? Remember, I am a noob at this and really want my book to be scientifically accurate. Thanks a ton for any help you can offer me! 

[_Augustus_]

1. One atmosphere of pressure.
2. 80 degrees fahrenheit.
3. You could use oxygen, helium, or hydrogen. All are equally safe.
4. No.
5. Hard...

[Bill Phil]

1 and 2: https://en.wikipedia.org/wiki/Atmosphere_of_Venus has a table of temperatures and pressures at varying heights (it doesn't really have a citation, so take it with a grain of salt)

3: You want buoyancy calculations, right? I'm not a buoyancy guy, but the math should be online.

4: Not very practical. Asteroids, while far away, would be more useful (especially since it's "easy" to brake it into orbit...)

5: You need energy. Where are you going to get it?

Edited September 28, 2016 by Bill Phil

[Andrew Zachary Foreman]

3 minutes ago, Bill Phil said:

1 and 2: https://en.wikipedia.org/wiki/Atmosphere_of_Venus has a table of temperatures and pressures at varying heights (it doesn't really have a citation, so take it with a grain of salt)

3: You want buoyancy calculations, right? I'm not a buoyancy guy, but the math should be online.

4: Not very practical. Asteroids, while far away, would be more useful (especially since it's "easy" to brake it into orbit...)

5: You need energy. Where are you going to get it?

1. & 2. I looked at the page. Do you have any idea why some people are saying it would be more like tropical weather at 50 km? 

3. Yeah, I need to know how much air I am going to need to lift the required mass for several hundred people to live. 

4. So the people that would be living above Venus most likely don't have the ability to reach asteroids. What is the second best option?

5. I read that Venus reflects 40% more solar energy than Earth, so that will account for some of it. Wind energy could also contribute as the wind speeds can reach 210 mph. I also plan to utilize a GMO bacterium that breaks down CO2 into energy and oxygen. Do you think that is feasible? 

48 minutes ago, _Augustus_ said:

1. One atmosphere of pressure.
2. 80 degrees fahrenheit.
3. You could use oxygen, helium, or hydrogen. All are equally safe.
4. No.
5. Hard...

Thanks. When you say 80 Fahrenheit do mean a range of 80 Fahrenheit, or that it would be 80 Fahrenheit at 50 km? If you mean the latter, how did you determine that?

Wouldn't hydrogen pose a danger of exploding? It seems like some gases would be better suited than others. 

[Bill Phil]

21 minutes ago, Andrew Zachary Foreman said:

1. & 2. I looked at the page. Do you have any idea why some people are saying it would be more like tropical weather at 50 km? 

3. Yeah, I need to know how much air I am going to need to lift the required mass for several hundred people to live. 

4. So the people that would be living above Venus most likely don't have the ability to reach asteroids. What is the second best option?

5. I read that Venus reflects 40% more solar energy than Earth, so that will account for some of it. Wind energy could also contribute as the wind speeds can reach 210 mph. I also plan to utilize a GMO bacterium that breaks down CO2 into energy and oxygen. Do you think that is feasible? 

Thanks. When you say 80 Fahrenheit do mean a range of 80 Fahrenheit, or that it would be 80 Fahrenheit at 50 km? If you mean the latter, how did you determine that?

Wouldn't hydrogen pose a danger of exploding? It seems like some gases would be better suited than others. 

1 & 2: I have no idea.

3: I can't help you there.

4: They likely do, after all, living in Venus' atmosphere implies a space faring species.

5: I don't know about the GMO bacterium creating energy from CO2, breaking it down usually takes energy.

Hydrogen can't explode when there is no Oxygen to oxidize it (like in Venus' atmo). It can catch fire in the habitat, though.

[Scotius]

How do you intend to get power from the wind farms on free floating dirigibles? You would have to anchor them to the ground - and good luck with that. Solar arrays needed to power up your floating colony would have to be enormous. As in very heavy. As in requiring even bigger airships to lift. And they would need protection from the sulphuric acid in the air - which would make them even heavier.

On Mars you are not only closer to the asteroid belt, you also have entire surface of the planet at your disposal. You will have ready source of water. You can build mines, have industry and agiculture. Still, many people on the forum will raise very valid points against the economy and doability of building self-sufficient colony there. How do you intend to achieve the same with a colony that is essentially a bunch of baloons floating above the closest equivalent to Hell we found so far, and still break at least even money-wise?

All of this was discussed on this forum ad nauseam. I'm not saying you should drop your ideas - but you have either to think very carefully about what you want to put inside it - or handwave a lot of stuff.

[peadar1987]

You could still harvest energy from wind shear. It would be a technical challenge, you'd probably have to drop a direction-insensitive turbine on a long cable, and it would have to be pretty robust, but it wouldn't be insurmountable. Just a question of transporting all the added mass associated with that to Venus, and the cost that implies

[radonek]

4 hours ago, Scotius said:

On Mars you are not only closer to the asteroid belt, you also have entire surface of the planet at your disposal. You will have ready source of water. You can build mines, have industry and agiculture. Still, many people on the forum will raise very valid points against the economy and doability of building self-sufficient colony there. How do you intend to achieve the same with a colony that is essentially a bunch of baloons floating above the closest equivalent to Hell we found so far, and still break at least even money-wise?

You have carbon, oxygen, hydrogen, sulfur and loads of free solar energy to power chemistry to make it into something valuable. It's hard to frame it into something plausible, but I will try:

My bet would be good 'ol hydrocarbons aka oil. Of course, earths fossil resources are long depleted and these have to be produced artificially. While it is certainly not wasted in cars anymore, it remains useful chemistry precursor (not least because there is a lot of inherited infrastructure) and one of best packages of chemical energy. Bioengineering is a good bet, so let's have some nice catastrophe that would lead to worldwide earthwide ban. Answer would be to move all bioindustry outside earth, because anything spaceborne is by definition contained and tightly controlled. Obviously, there would have to be already established infrastructure to build stuff in space - hauling everything up the Well is not going to work out. So lets assume asteroid mining is a thing already and this dangeours biostuff is actually a last thing to poison earth. Conglomerates of biotech corporations just need to order development and production of necessary technology in Geo or Phobian shipyards and move their business to Titan, Io, Venus or anywhere useful really (IMO that would be mostly just plain space).

Note this changes OPs scenario a bit, human settlement is just cream on top of much larger industrial complex, working at various heights depths. And I mean LARGE - moving stuff around solar system is not going to work out unless we are talking some serious economy of scale. Energy budget of chemistry involved is so big that moving in a bit of uranium to power machinery is just negligible. Venus would be about most difficult of such places anyway, since one need to spend lots of produce just to make fuel to get stuff up to orbit. But inhabitants are proud of it because hey, at least we don't have to spend lives in pressurized radiation hardened cans like stinky martians.
 

[Andrew Zachary Foreman]

10 hours ago, Bill Phil said:

1 & 2: I have no idea.

3: I can't help you there.

4: They likely do, after all, living in Venus' atmosphere implies a space faring species.

5: I don't know about the GMO bacterium creating energy from CO2, breaking it down usually takes energy.

Hydrogen can't explode when there is no Oxygen to oxidize it (like in Venus' atmo). It can catch fire in the habitat, though.

Awesome! Thanks! The concept for the book is that the colonists were put there and then lost all contact with Earth. They didn't have enough resources to get outside of Venus and back to Earth so they decided to stay. Eventually they learned how to survive and lost all desire to waste the resources to find out what happened. 

Catching fire on the habitat would kind of suck...

6 hours ago, Scotius said:

How do you intend to get power from the wind farms on free floating dirigibles? You would have to anchor them to the ground - and good luck with that. Solar arrays needed to power up your floating colony would have to be enormous. As in very heavy. As in requiring even bigger airships to lift. And they would need protection from the sulphuric acid in the air - which would make them even heavier.

On Mars you are not only closer to the asteroid belt, you also have entire surface of the planet at your disposal. You will have ready source of water. You can build mines, have industry and agiculture. Still, many people on the forum will raise very valid points against the economy and doability of building self-sufficient colony there. How do you intend to achieve the same with a colony that is essentially a bunch of baloons floating above the closest equivalent to Hell we found so far, and still break at least even money-wise?

All of this was discussed on this forum ad nauseam. I'm not saying you should drop your ideas - but you have either to think very carefully about what you want to put inside it - or handwave a lot of stuff.

I don't have an issue with massive balloons required to lift the colonies. Collecting resources still remains my chief problem. I only care about lifting ratio so i know how big the balloon needs to be. 

3 hours ago, peadar1987 said:

You could still harvest energy from wind shear. It would be a technical challenge, you'd probably have to drop a direction-insensitive turbine on a long cable, and it would have to be pretty robust, but it wouldn't be insurmountable. Just a question of transporting all the added mass associated with that to Venus, and the cost that implies

That is my big kicker right now. I don't need a thorough explanation for how they got there. Just how they managed to survive.  

[Scotius]

Without ability to contact Earth\interplanetary travel? Short answer: They didn't. Unless you follow radonek's idea and build a massive industrial complex before the catastrophe. To survive you need resources and energy. To get energy you need even more resources to build wind turbines, solar panels, nuclear reactors. If you can't get them from the surface of Venus, your colony is doomed. If you have means to get them from the bowels of Hell Venus surface, you most likely have the means to get your people somewhere less deadly and difficult to live (a.k.a. interplanetary travel).

[radonek]

10 minutes ago, Andrew Zachary Foreman said:

…Eventually they learned how to survive…

IMO this is not going to work out unless they learn how to mine resources from surface. If you want them to be long-term self-sufficient, they'd need metals for industrial production and chemicals for maintaining biosphere. They can probably get without metals to some degree by substituting carbon based materials (fullerens to the rescue again :-) but not everything. And no closed ecosystem is 100% effective, your colonists will be slowly losing trace elements and would eventually die out due to lack of phosphorus or something.
 

[Andrew Zachary Foreman]

8 hours ago, radonek said:

You have carbon, oxygen, hydrogen, sulfur and loads of free solar energy to power chemistry to make it into something valuable. It's hard to frame it into something plausible, but I will try:

My bet would be good 'ol hydrocarbons aka oil. Of course, earths fossil resources are long depleted and these have to be produced artificially. While it is certainly not wasted in cars anymore, it remains useful chemistry precursor (not least because there is a lot of inherited infrastructure) and one of best packages of chemical energy. Bioengineering is a good bet, so let's have some nice catastrophe that would lead to worldwide earthwide ban. Answer would be to move all bioindustry outside earth, because anything spaceborne is by definition contained and tightly controlled. Obviously, there would have to be already established infrastructure to build stuff in space - hauling everything up the Well is not going to work out. So lets assume asteroid mining is a thing already and this dangeours biostuff is actually a last thing to poison earth. Conglomerates of biotech corporations just need to order development and production of necessary technology in Geo or Phobian shipyards and move their business to Titan, Io, Venus or anywhere useful really (IMO that would be mostly just plain space).

Note this changes OPs scenario a bit, human settlement is just cream on top of much larger industrial complex, working at various heights depths. And I mean LARGE - moving stuff around solar system is not going to work out unless we are talking some serious economy of scale. Energy budget of chemistry involved is so big that moving in a bit of uranium to power machinery is just negligible. Venus would be about most difficult of such places anyway, since one need to spend lots of produce just to make fuel to get stuff up to orbit. But inhabitants are proud of it because hey, at least we don't have to spend lives in pressurized radiation hardened cans like stinky martians.
 

This wouldn't work with the plot I have set up in the book though, although you do have it right that Venusians would be a very proud people. Due to the nature in which they lost all contact with Earth Venusians became very fearful and superstitious about what was going on in greater space, and any spaceships traveling between planets would have disappeared at about the same time as well. This would mean that they reengineering their habitats for space travel would be impossible. So they are trapped. Are there any workarounds? This is set at the bare minimum, thirty or forty years down the road, so they would have some tech at their disposal that we do not. 

8 hours ago, Scotius said:

Without ability to contact Earth\interplanetary travel? Short answer: They didn't. Unless you follow radonek's idea and build a massive industrial complex before the catastrophe. To survive you need resources and energy. To get energy you need even more resources to build wind turbines, solar panels, nuclear reactors. If you can't get them from the surface of Venus, your colony is doomed. If you have means to get them from the bowels of Hell Venus surface, you most likely have the means to get your people somewhere less deadly and difficult to live (a.k.a. interplanetary travel).

I big part of my book is that when Earth went off the radar all people currently living above Venus experienced radio silence. This caused superstition and fear as to why there was no contact and this would have pushed them to stay out of space at all costs. At some point I do plan to introduce other humans that have advanced, interplanetary travel tech, so let's say they only need to survive for fifty through a hundred years. What can you give me? 

 

8 hours ago, radonek said:

IMO this is not going to work out unless they learn how to mine resources from surface. If you want them to be long-term self-sufficient, they'd need metals for industrial production and chemicals for maintaining biosphere. They can probably get without metals to some degree by substituting carbon based materials (fullerens to the rescue again :-) but not everything. And no closed ecosystem is 100% effective, your colonists will be slowly losing trace elements and would eventually die out due to lack of phosphorus or something.
 

How long do you think they could get by, assuming they were running like a well oiled machine before before everything happened? Also, what would it take to mine minerals off the surface? As I understand we wouldn't have that ability with current tech. 

[DerekL1963]

1 hour ago, Andrew Zachary Foreman said:

This is set at the bare minimum, thirty or forty years down the road, so they would have some tech at their disposal that we do not.

As is generally the case, the problem isn't tech - it's infrastructure and keeping that infrastructure functional for decades without support. 

[todofwar]

My two cents: forget mining. Not needed for your scenario. You won't be building new habitats unless that was your starting goal. But you can probably get by with as close to a closed loop as possible. The daily requirements for things like iron and calcium are incredibly low, a single block of iron will be good for your 100 people. So there's really nothing needed from the surface. For general repair they could use plastics, some conductive polymers have been developed that they could use for circuitry.

As for energy, that's Venus's number one strength. You got thermal gradients and strong vertical wind shear, so drop a pipe and pour some water in to get a geothermal style system, and attach wind turbines to simultaneously get wind energy.

I would say that you can't have a perfect closed loop, but that just adds to the tension as they watch their habitat slowly but inevitably crumble around them. 

[todofwar]

For the sulfuric acid, you can probably use some kind of bacterial vat. Sulfates are the bioavailable form of sulfur, which is a micronutrient. So some enzyme somewhere is breaking it down. Or you can extract H2, you'll have to provide some kind of cation, but then you can take co2 to o2 and c and react the o2 with h2 to get water.

H2so4 to 2h+ and so42-, 

H+ to h2, 

And so on.

[radonek]

4 hours ago, Andrew Zachary Foreman said:

This caused superstition and fear…

 

 

 

This wont fly. I can't imagine how can highly trained astronauts turn into such superstitious simpletons in a first place, much less how would said idiots be able to run life support machinery without causing fatal catastrophe. Unless you posit some incredibly advanced technology that can take care of itself, any extraterrestrial colony is bound to consist of intelligent, educated and forward looking people. Either that, or dead people.
 

4 hours ago, Andrew Zachary Foreman said:

How long do you think they could get by, assuming they were running like a well oiled machine before before everything happened? Also, what would it take to mine minerals off the surface? As I understand we wouldn't have that ability with current tech.

Years, centuries, anything. It obviously depends a lot on  technology and size of ecosystem. If you grow food (hydropony?) crops are probably most susceptible.  And it would probably be easy to have huge stock of _trace_ elements. My point is, even if it would take a long time, they would know that their ecology is not sustainable. They would even be able to track rate of degradation and project pretty accurate timeline of decaying life conditions. This is not exactly conductive to your idea of forgetting about space travel. Mining surface is certainly possible, but would be very complex and with quite an attrition rate. Its hard to image how you could pull that off yet remain unable to reach orbit.
 

[todofwar]

34 minutes ago, radonek said:

 

 

 

This wont fly. I can't imagine how can highly trained astronauts turn into such superstitious simpletons in a first place, much less how would said idiots be able to run life support machinery without causing fatal catastrophe. Unless you posit some incredibly advanced technology that can take care of itself, any extraterrestrial colony is bound to consist of intelligent, educated and forward looking people. Either that, or dead people.
 

Years, centuries, anything. It obviously depends a lot on  technology and size of ecosystem. If you grow food (hydropony?) crops are probably most susceptible.  And it would probably be easy to have huge stock of _trace_ elements. My point is, even if it would take a long time, they would know that their ecology is not sustainable. They would even be able to track rate of degradation and project pretty accurate timeline of decaying life conditions. This is not exactly conductive to your idea of forgetting about space travel. Mining surface is certainly possible, but would be very complex and with quite an attrition rate. Its hard to image how you could pull that off yet remain unable to reach orbit.
 

You have a very optimistic view of humans. Human nature doesn't change, I think superstitions and fear can creep in easily. Without necessarily compromising their ability to run the ship. Hell, at a certain point it will be more about knowing the intricacies of the ship, not the derivation of the laws of buoyancy. 

[Bill Phil]

50 minutes ago, radonek said:

This wont fly. I can't imagine how can highly trained astronauts turn into such superstitious simpletons in a first place, much less how would said idiots be able to run life support machinery without causing fatal catastrophe. Unless you posit some incredibly advanced technology that can take care of itself, any extraterrestrial colony is bound to consist of intelligent, educated and forward looking people. Either that, or dead people.
 

Who said they were all well trained astronauts? Unless that is the case, then it is possible.

[Andrew Zachary Foreman]

First off, thanks to everyone who has contributed! Your feedback is fantastic, and is a major boon to my research. If any of you are curious, you can check out my blog here, azfstories.worpress.com. I am posting frequent updates on the book if anyone wants to see what ideas I am pulling off of here. The next post will be up tomorrow night. 

 

4 hours ago, DerekL1963 said:

As is generally the case, the problem isn't tech - it's infrastructure and keeping that infrastructure functional for decades without support. 

Thanks. That is actually a really good point as it would be very tough. The major crisis in the first book will be overcoming a massive system malfunction. 

 

4 hours ago, todofwar said:

My two cents: forget mining. Not needed for your scenario. You won't be building new habitats unless that was your starting goal. But you can probably get by with as close to a closed loop as possible. The daily requirements for things like iron and calcium are incredibly low, a single block of iron will be good for your 100 people. So there's really nothing needed from the surface. For general repair they could use plastics, some conductive polymers have been developed that they could use for circuitry.

As for energy, that's Venus's number one strength. You got thermal gradients and strong vertical wind shear, so drop a pipe and pour some water in to get a geothermal style system, and attach wind turbines to simultaneously get wind energy.

I would say that you can't have a perfect closed loop, but that just adds to the tension as they watch their habitat slowly but inevitably crumble around them. 

I know almost nothing about how a geothermal system would work. I understand that Venus gets about 40% more solar energy than Earth, and if you assume that efficiency rates will have improved over the course of several decades it seems like the best way to get energy would be to focus on solar. What are your thoughts on that? 

 

4 hours ago, todofwar said:

For the sulfuric acid, you can probably use some kind of bacterial vat. Sulfates are the bioavailable form of sulfur, which is a micronutrient. So some enzyme somewhere is breaking it down. Or you can extract H2, you'll have to provide some kind of cation, but then you can take co2 to o2 and c and react the o2 with h2 to get water.

H2so4 to 2h+ and so42-, 

H+ to h2, 

And so on.

Ok....A little over my head but ok. Could this bacterial vat hypothetically meet all of the water needs of a colony housing a couple hundred people? Also, should I consider using this as a means to create hydrogen to lift the colony, or is that not worth my time? This is just a thought. I still think it makes more sense to use a breathable mix of air. 

 

1 hour ago, radonek said:

 

 

 

This wont fly. I can't imagine how can highly trained astronauts turn into such superstitious simpletons in a first place, much less how would said idiots be able to run life support machinery without causing fatal catastrophe. Unless you posit some incredibly advanced technology that can take care of itself, any extraterrestrial colony is bound to consist of intelligent, educated and forward looking people. Either that, or dead people.
 

Years, centuries, anything. It obviously depends a lot on  technology and size of ecosystem. If you grow food (hydropony?) crops are probably most susceptible.  And it would probably be easy to have huge stock of _trace_ elements. My point is, even if it would take a long time, they would know that their ecology is not sustainable. They would even be able to track rate of degradation and project pretty accurate timeline of decaying life conditions. This is not exactly conductive to your idea of forgetting about space travel. Mining surface is certainly possible, but would be very complex and with quite an attrition rate. Its hard to image how you could pull that off yet remain unable to reach orbit.
 

They would be very intelligent, yes. It is assumed that initial colonists would have to be vetted. It is very important for the plot of the book that they cannot access outer space. Do you have a better suggestion for what would hold them back? 

 

46 minutes ago, todofwar said:

You have a very optimistic view of humans. Human nature doesn't change, I think superstitions and fear can creep in easily. Without necessarily compromising their ability to run the ship. Hell, at a certain point it will be more about knowing the intricacies of the ship, not the derivation of the laws of buoyancy. 

I am starting to realize that I need to focus more on the life support systems on the ship. It is going to have to be absolutely massive. My starting idea was to make it big enough to fully support 500 people. Now that seems unrealistic. 

 

37 minutes ago, Bill Phil said:

Who said they were all well trained astronauts? Unless that is the case, then it is possible.

Most of the first generation would be highly skilled, although much of the education would have to deal with meteorology and surviving in the atmosphere. Successive generations would have a broader scope in purpose. 

[kerbiloid]

On 28.09.2016 at 5:10 AM, Andrew Zachary Foreman said:

1. & 2. I looked at the page. Do you have any idea why some people are saying it would be more like tropical weather at 50 km? 

Not at 50 - at 55 km. 27°C and 0.5 atm.
Sulfuric acid concentration looks not that high.
But still without breathable air,, of course.
So, like a weather near a coke oven of a metallurgical plant in tropics.

On 28.09.2016 at 5:10 AM, Andrew Zachary Foreman said:

3. Yeah, I need to know how much air I am going to need to lift the required mass for several hundred people to live. 

Carbon dioxide density is nearly twice greater than air's. Would be ~1 kg/m³ for ~0.5 atm pressure.
So, Volume of balloon, m³ = Mass of craft, kg / (1 kg/m³ - density of gas inside balloon, kg/m³ )

22 hours ago, Scotius said:

You would have to anchor them to the ground - and good luck with that.

On a 40 km long chain...
With such kite on a rope they should just put a generator instead of anchor.

They would gather CO₂ and convert it to carbon instead of mining.

[Scotius]

Heh. 40 km of anything will weight A LOT! And because of the power of venusian winds it couldn't be flimsy. You will need baloons the size od small countries to bear that weight - which of course will create even more problems with wind.

[HebaruSan]

What about beaming power from orbit? How massive would the ground station need to be?

[todofwar]

4 hours ago, Scotius said:

Heh. 40 km of anything will weight A LOT! And because of the power of venusian winds it couldn't be flimsy. You will need baloons the size od small countries to bear that weight - which of course will create even more problems with wind.

Not necessarily. And you don't need 40 km, there's some good data on variable wind speeds at different altitudes, a couple km will do fine. And you would wrap the cable in a long balloon of its own. The size of the habitat helps in this case, it works like a big anchor preventing the kite from accelerating the habitat to the point that your wind energy is useless. 

Solar can work, and we're not fat away from efficient organic solar cells, if this is near future they could conceivably use carbon from the atmosphere with hydrogen from the acid to make some voltaics.

[Andrew Zachary Foreman]

9 hours ago, kerbiloid said:

Not at 50 - at 55 km. 27°C and 0.5 atm.
Sulfuric acid concentration looks not that high.
But still without breathable air,, of course.
So, like a weather near a coke oven of a metallurgical plant in tropics.

Carbon dioxide density is nearly twice greater than air's. Would be ~1 kg/m³ for ~0.5 atm pressure.
So, Volume of balloon, m³ = Mass of craft, kg / (1 kg/m³ - density of gas inside balloon, kg/m³ )

On a 40 km long chain...
With such kite on a rope they should just put a generator instead of anchor.

They would gather CO₂ and convert it to carbon instead of mining.

Why do I need a chain? I want the airships to be able to travel across the planet. What could I use carbon for? could that really meet all of their material needs? Would you mind explaining the air/mass ratio in terms I can understand? I think you are saying that for every ton of mass I have I need three tons of air. And that would be at .5 atm? What if it were lower? I think that having the aircraft lower and investing more in a heat reduction system would better serve our purposes. 

 

8 hours ago, Scotius said:

Heh. 40 km of anything will weight A LOT! And because of the power of venusian winds it couldn't be flimsy. You will need baloons the size od small countries to bear that weight - which of course will create even more problems with wind.

Balloons the size of small countries are definitely not going to work. 

 

5 hours ago, HebaruSan said:

What about beaming power from orbit? How massive would the ground station need to be?

Not possible. They are "air locked" so to speak. Their tech makes long stays on the ground unfeasible, and they are terrified of returning to orbit. I have thought about the possibility that they could mine resources from the tops of mountains, but that still might require a stretch of imagination. 

 

4 hours ago, todofwar said:

Not necessarily. And you don't need 40 km, there's some good data on variable wind speeds at different altitudes, a couple km will do fine. And you would wrap the cable in a long balloon of its own. The size of the habitat helps in this case, it works like a big anchor preventing the kite from accelerating the habitat to the point that your wind energy is useless. 

Solar can work, and we're not fat away from efficient organic solar cells, if this is near future they could conceivably use carbon from the atmosphere with hydrogen from the acid to make some voltaics.

Are you saying to ignore wind energy and go for solar? That sounds way better. Although I am concerned with weight that all of those solar cells will add. 

[Scotius]

3 minutes ago, Andrew Zachary Foreman said:

What could I use carbon for?

Everything possible. You should get it by now - if you can't bring the materials from the space (asteroids, other planets and moons), and you can't mine it on Venus, carbon extracted from the atmosphere is the only building material you will have in relative abundance. Carbon fibers, fullerenes, graphene, nanotubes - your colonists will have to use them for everything. From hulls of the habitats to tableware, shoes and hair combs.