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I was just wondering what Earth's global climate would be like if the planet was surrounded / encapsulated by transparent solar panels. What would happen to our atmosphere?

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closed as too broad by Hohmannfan, J_F_B_M, bowlturner, T3 H40 supports Monica, clem steredenn Apr 23 '16 at 20:05

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    $\begingroup$ Transparent solar panels are a contradiction in terms. Either they catch solar energy, or they are transparent, but not both at the same time. $\endgroup$ – o.m. Apr 23 '16 at 12:46
  • $\begingroup$ It is theoretically possible for the panels to absorb one wavelength (e.g. UV) but pass another (e.g. visible). However, we don't have any that can do that now. $\endgroup$ – Jim2B Apr 23 '16 at 12:55
  • $\begingroup$ @Jim2B We don't have the technology to completely surround the planet with a solid shell either, so we are in the realm of science fiction anyway. $\endgroup$ – Philipp Apr 23 '16 at 15:02
  • $\begingroup$ @Jim2B There are transparent solar panels in existence right now. As far as I know, there are no large-scale commercial applications, but transparent solar panels do exist. $\endgroup$ – AmiralPatate Apr 23 '16 at 15:30
  • $\begingroup$ @Philipp: The panels wouldn't have to be in a solid shell, There could be myriads of smaller panels, each in its own independent orbit. Think Saturn's rings, but not limted to one plane. $\endgroup$ – jamesqf Apr 23 '16 at 18:03
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"Transparent solar panel" is an oxymoron. A solar panel gains energy by absorbing light and turning it into electricity. That absorbed light obviously doesn't come out on the other side. Any light it leaves through can not be turned into electricity.

Also, solar-panels are not 100% effective. Only a small percentage of light gets turned into electricity. The rest gets turned into heat which heats up the solar panel and then gets radiated away in form of infra-red light (most of it back into the direction it came from because that side will heat up the most, but some of it will also come out on the other side).

But it is possible to have solar panels which are transparent in the visible spectrum and only absorb those wavelengths which are invisible to humans, like infra-red or ultra-violet. Such solar panels already exist today. That way they would still leave through visible light and the sun would appear just as bright as usual. Candidate number one would be UV light which causes more harm than good to us.

However, the planetary surface will get cooler by that. That's a thermodynamic imperative. Every watt of energy you extract with the solar panel shell will be a watt less to heat up the atmosphere and surface. By how much depends on which wavelengths you filter and how much you still leave through. This graphic can help you to calculate it yourself: Spectrum of solar radiationimage source: Wikipedia

To calculate the energy, take the cross-section of Earth in square-meter (128 * 10^14 m²), multiply it by the width of the spectrum you want to absorb in nm and by the average irradiance in that spectrum according to the image above.

For example, if you want to filter out the wavelength of 300-400nm in orbit you would get about (128 * 10^14 m² * 100nm * 1 W/m²/nm) = up to 1,280,000 Terawatt of energy you would get as electricity but not as heat.

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