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Assumptions:

  • We have materials that can withstand the temperatures/pressures/acidity of Venus.

  • We can get to Venus and back reasonably easily (NASA does shuttles every 3 months).

Here is Venus:

enter image description here

From what I know, water boils at 100 C (at sea level on Earth) and the pressure on Venus at 40.5 km is the same as on Earth at sea level. Finally, the temperature on Venus at ~40 km is 100 C.

So would this work:

enter image description here

Water is heated to gas, goes through turbine and makes electricity and then gets pumped back up and cools to liquid and then the cycle goes again.

Would this create energy without using more than is required?

Next question, how would we get that energy back to Earth? I have a semi-idea:

  • Incredibly powerful lasers, onto solar panels on the Earth.

    • These could shine either visible light, or maybe a wavelength on the electromagnetic spectrum that doesn't get absorbed by the atmosphere.
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  • $\begingroup$ This is at our current level of technology, plus the stuff you listed? $\endgroup$ – HDE 226868 Mar 29 '15 at 23:11
  • $\begingroup$ theres not enough water in venus $\endgroup$ – Jorge Aldo Mar 30 '15 at 1:06
  • $\begingroup$ Very often the lasers will be blocked by the sun... $\endgroup$ – Tom Harrington Mar 30 '15 at 2:49
  • $\begingroup$ @HDE226868 yes that's all. @JorgeAldo we would take the water as well as the materials. @Tom Would you ever be able to store the energy on Venus some how? ` $\endgroup$ – Tim Mar 30 '15 at 9:53
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    $\begingroup$ @TomHarrington - Blocked by the sun very often??! It's a couple of days every 19+ months. $\endgroup$ – Rex Kerr Mar 30 '15 at 12:27
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This is a horrible idea, not because it wouldn't work (there have been similar power-generation schemes in Earth's oceans) but because the atmosphere of Venus is hellish: it's made of sulphuric acid and winds blow at hundreds of miles per hour.

There's hardly a spot in the solar system less friendly to a water-containing turbine system.

If you have the technology to put all those materials in orbit around Venus and somehow drop them into the atmosphere (float them?), just use the same resources to build a bunch of space-based mirrors and/or solar panels. You'll get way more power, with way less trouble.

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    $\begingroup$ Well there was a support in the diagram... $\endgroup$ – Tim Mar 30 '15 at 9:53
  • $\begingroup$ @Tim - I was generously ignoring that. Do you fancy building a 40 kilometer tall building in concentrated sulphuric acid vapor blowing at hunrdreds of kph? I don't! $\endgroup$ – Rex Kerr Mar 30 '15 at 12:08
  • $\begingroup$ Fair point. Some sort of air ship could probably be used...? $\endgroup$ – Tim Mar 30 '15 at 12:09
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    $\begingroup$ @Tim - Perhaps, but it's a really difficult engineering challenge for no benefit. It's like harvesting wood from the moon: yes, technically possible, but so much easier to do other ways that you'd never do it that way. $\endgroup$ – Rex Kerr Mar 30 '15 at 12:11
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    $\begingroup$ @RexKerr You know there'd be a niche market for moonwood furniture... And now I want to read that short story. (Moonoak's the holy grail, but the long growth period makes it a risky investment; The safe money's in lunar eucalyptus and bamboo.) $\endgroup$ – user867 Oct 26 '15 at 7:00
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This would actually work as you describe (assuming all your material/technology requirements are met, as you do). However, there is a practical issue. Unless you have some super-high-density energy storage medium, you will probably be beaming your energy back as a maser or laser (also as you describe).

Let's stop and think for a second. Where is the energy to support that atmospheric temperature gradient coming from? The Sun of course! The Sun heats the planet/atmosphere, and the heat is trapped by the greenhouse effect. This effectively makes your power-generation scheme a roundabout solar generator.

If you have the technology to efficiently convert your energy beam into usable power, then you also have the technology to efficiently convert raw sunlight into power. Solar panels will be much more efficient at generating power: the theoretical limits are somewhere around 50%, while the thermal efficiency limits on a thermal engine with a hot-side temperature of only 100 C (assuming a cold-side temperature near 0 C) is much lower, around 25% (even discounting the mechanical and secondary conversion losses).

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It is possible however a horribly inefficient use of materials.
Venus' atmosphere contains 96.5% CO2, 3.4% Nitrogen and other gasses with the major one being, sulfur dioxide.
The atmospheric pressure is also 93-98 times more than earth, the same as being about 1km underwater. A probe has been crushed 18km above the surface.
Also, the surface temperature is 450 degrees celsius which can melt lead so goodbye cheap radiation shielding.
And the nice fluffy clouds you see are sulphuric acid.

As you said we have such materials but would it not be easier to build something that is efficient?


If you want to build something that needs to get a lot of energy then I would suggest building a massive solar array in space because it will require less maintenance, is a lot more "human" friendly and probably costs a lot fewer resources.
To send the energy back to earth you could:

  1. Use a laser.
  2. Save the energy in nano-tube power banks.
  3. You are currently using a semi-solar solution but if you convert to full solar power you will have a lot more energy to work with.

    *semi-solar because the greenhouse gasses which keep the warmth from the sun that in the end warms the water. Also: because the pressure is a lot higher your water will only start boiling at a mere 300 degrees celsius

If you are however determined to build on venus I would suggest:

  • Shipping the energy in batteries. You can use the sulphuric acid as an electrolyte.
  • You can use the sulphuric acid to react with metals and create hydrogen gas. This gas is extremely flammable and can be used to power a "conventional" engine.

Bonus point:
Theoretically you could terraform the planet to suit your need but this would be very expensive but afterwards, could be used as a hospitable colonization for humans without needing to transport the energy.

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  • $\begingroup$ I took the pressure into account by building it 40km in the air. A little engineering challenge, I must say. $\endgroup$ – Tim Nov 28 '16 at 17:15
  • $\begingroup$ But it only reaches 1G from 50km+ at 40km its about 5G's $\endgroup$ – Selene Blok Nov 29 '16 at 14:07
  • $\begingroup$ ahh good point. 40km is the point it's 100°C, not the level water boils Likely a little higher would be needed. $\endgroup$ – Tim Nov 29 '16 at 14:09
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Even with the assumptions you made this is still not a good idea.

What you described probably wouldn't work. I might be mistaking but it sounds like violating 2nd law of thermodynamics. In geothermal plants on earth pressure is not as high as Venus. Maybe do a bit more research on geothermal electricity.

There is another way however that you can generate electricity on Venus. By directing convection flows. Have a look at solar updraft towers

But these are very inefficient method for electricity generation. The more I think about it, it makes no sense to generate electricity on Venus. And there are a lot better ways to do in earth orbit or moon.

If you want to have a factory on Venus and want it to make sense scientifically, why not some floating factories extracting minerals (maybe sulfur) and shipping them to earth.

Have a look at Venus floating cities. The air in the city is less dense than Venus atmosphere so it floats.

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  • $\begingroup$ I don't see how that law is broken - it's the same concept as geothermal. Also, they do pressurise the water... $\endgroup$ – Tim Mar 30 '15 at 10:15
  • $\begingroup$ Thanks for the minus. I said probably, and stressed that I may be mistaking. I was just trying to send u some pointers as to where to get more scientifically feasible ideas $\endgroup$ – A squared Mar 30 '15 at 10:43
  • $\begingroup$ do an edit and i'll take away the dv $\endgroup$ – Tim Mar 30 '15 at 10:53
  • $\begingroup$ What do you want me to say??? $\endgroup$ – A squared Mar 30 '15 at 11:28
  • $\begingroup$ just any small edit, add a space or something $\endgroup$ – Tim Mar 30 '15 at 11:29

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