Is there anything keeping us from building a gigantic solar array on the moon

[zephyrprime]

The moon is no good. Any given spot on the moon is in the dark 14 out of 28 days. Orbiting solar panels are more plausible.

 

[rivan]

Originally posted by: FoBoT

Originally posted by: funboy42
We have never landed on the moon, it was faked, therefore it would cost too much to actually figure out how to really land on it, and set up the device you mention.

but the moon is really just a light bulb behind the sky screen, it isn't like it is really a place you can go at all

Silly. The moon is made of cheese.

 

[sygyzy]

How much power is loss when transmitted via microwave or laser?

 

[jjzelinski]

Originally posted by: sygyzy
How much power is loss when transmitted via microwave or laser?

Well for a 500KW Peak pulse from a radar's feedhorn ,the attenuation is something on the order +50dBm after a few inches. Granted the feedhorn doesn't emanate a focused beam but the loss is still quite severe. I agree with a the poster above he mentioned you would need a way to isolate the beam from the atmosphere somehow which obviously does not seem feasible.

More fundamentally though the question is begged, "why the moon?" Do we not have massive amounts land space available already?

EDIT: re-read the OP, unforseen impacts of solar arrays; got it

 

[libs0n]

Originally posted by: BD2003

Originally posted by: rivan

Originally posted by: BD2003

Originally posted by: rivan

Originally posted by: rivan

Originally posted by: sygyzy
Aside from the aforementioned space trash that pummels the moon all the time, how do you transmit power "wirelessly"?

Via microwave, apparently, though I'd have thought laser would be a candidate too.

Clearly, I can think of nothing original.

Surely it can be done, but for it to be worth building, itd pretty much have to be able to power the entire world, and thats a hell of a lot of energy to beam down from space without melting a hole through the earth. Its one thing to say CO2 causes a temperature rise, but its pretty damn obvious that beaming petawatts of energy through the atmosphere at a single point is going to warm it up.

It's probably a much better, not to mention more economically feasible idea for even the distant future, to blanket the sahara with solar panels, or send free floating turbines out to sea. That way if anything goes wrong, it can be replaced piece by piece, rather than a catastrophic power station satellite plummeting down to earth.

The whole point is to get our energy from sources outside our own ecosystem. A solar array blanketing the sahara would almost certainly have a significant impact on the weather of the region, possibly the globe.

I guarantee that microwaving massive amounts of power down through space will have a significant impact on the weather of the region, and possibly the globe. You might be able to focus a beam, but unless its shielded from the water vapor in the air, it will heat up and do the same. Theres just no way to insulate it.

The recieving antenna for a space solar satellite would be a wire mesh spread over several square kilometers. From what I recall, the power density spread over that area wouldn't exceed what it receives already from sunlight. Distributing the microwave beam over a wide area in order to reduce its power density and thus make it safe is why space solar power concepts have such gigantic receiving antennas. Most rectenna ideas I've seen have the space underneath used for farmland, and the frequencies used by the microwave transmission chosen to avoid transmission losses. In order to heat up water vapour, you must expend energy, and that's a terrible no-no in the margins of microwave power transmission. Lasers are not proposed as the transmission method as losses are too great; something like 90% of the power you send can be picked up by the rectenna and put into the grid. A hell of a lot of energy already hits the Earth already, Sunlight. My throwaway solar power hype lines may be off, but something like all the energy mankind uses in a year hits the Earth through the suns rays in an afternoon. Also, most of these concepts propose placing the SPS in a geosynchronous earth orbit, so that it is always facing the receiving station for power transmission, and I don't think that such an orbit decays in such a way as for its objects to plummet into the Earth. While raising safety questions is perfectly legitimate, this concept isn't as dangerous as you think.

The benefits of space solar power is that it is continuous, in that there is no night in space, and that the platform would be above the diluting effects of the atmosphere. This works out to something like 4 times the solar power being generated per panel compared with it being on Earth's surface. Moon power throws the benefits of space solar power out the window: the 14 day night, the transmission losses beaming power from the moons surface to the Earth's. It's nuts. Space solar power is less nutty, but it would require greatly reduced launch costs and perhaps even space resource utilization to reduce its exorbitant price tag, neither of which are reasonably on the horizon. Even then it has other problems, like the cost of the rectenna and the transmitter/panels. That's not to say I don't thing its a neat idea, and its a power generation method I would favour, if it were an option.