Space based solar plant gets go ahead

[Kal]

article (http://www.tgdaily.com/sustainability-features/44934-space-based-solar-plant-gets-go-ahead )

I know Japan is thinking of doing something along these lines as well.

How will it effect us astronomers if we have satellites that are more than a kilometer wide up above us? :shrug:

[jjjnettie]

What will they think???
Ooooh, I'll image that.
LOLOL

[renormalised]

They weren't thinking of astronomers (or anyone else, for that matter) when they proposed this. Not being able to see the stars will be the least of their worries if this thing goes up. What if the satellite strays out of alignment a bit...remember, they're going to beam the power down via microwave link. Tens of thousands of gigawatts of electrical energy coming down what will essentially be a microwave laser beam....hmmmm:screwy:

Normally, the microwave (or in this case radio) link would attenuate over a large area after beaming into the atmosphere, but in order to be able to carry the current efficiently, they will have to focus the beam very tightly and precisely, so as to lose as little energy as possible...otherwise it'd be useless trying to beam the energy down as it would leak away. Quite frankly, I don't think they've thought through the engineering and science side of this project well enough to be proposing anything like this, yet.

[OzRob]

I would assume that these things would be geo-stationary so unless you lived near one of the ground stations it will not affect your view of the sky. Also, unless I am missing something, they will not be reflecting any light at night.

[renormalised]

Like I said, what if the satellite strays out of alignment...it does happen.

Not only that, remember they have to beam this energy down...it's not just a kilometer wide satellite they're putting up there. It's all the ancillary collecting and transmission equipment capable of handling the huge current load, that's also got to go up. What are they going to launch it in?? And how are they going to maintain it when it breaks down, as it inevitably will. They're flat out getting anyone out of LEO, let alone to geostationary orbit or a lagrangian point.

Like I said, this hasn't been thought over thoroughly enough.

[OzRob]

I guess they are not going to put the ground stations near residential areas. I would hope not..... :eyepop:

I would suspect that they would use fail-safe mechanisms to prevent the inadvertent cooking of people. For example, a ground-based laser could be used to ensure that the station is lined up properly. If the satellite losses the signal it automatically shuts down.

I'm guessing that some very bright people are working on this. If it can be done safely and economically clean energy will be plentiful.

[JimmyH155]

OK OZ Rob, so no transmissions at night??
Sounds like that story of the Irish astronauts who wanted to fly to the Sun and one says "Won't it get a bit hot as we approach it??" and the other says "No it'll be alright, we'll go by night!":lol::lol::lol:
Sorry, corny joke, I know:D

[Jen]

:lol::lol::lol:

[Rhino1980]

Bring it on. We need to build one to weigh up whether it is a viable alternative to 'burning stuff' to make electricity. Don't knock it till ya try it LOL

[Octane]

Maybe they can stick it at the South Celestial Pole so we have something to polar align to.

Regards,
Humayun

[jjjnettie]

Now there's a plan.
Smart thinkin' Humayun.

[mswhin63]

I am pretty sure that they would have figured out alignment issues, I have repaired line of sight microwave transmitters and receivers and it is so easy to shut down or switch over if the system if it out of alignment.

I learnt this radio technique over 10 years ago and it was essential for consistant operations.

I'd bring it on, the obstruction should only be minor.

[tlgerdes]

Sounds a bit like a James Bond movie to me :lol:

[multiweb]

:lol: :rofl: :thumbsup:

[renormalised]

And here we are trying to prevent sea level rise:eyepop::P:D

[Kal]

Do you think it is possible that they could transform it into some sort of space based weapon if they wanted to? I assume it would have some small rockets (or ion engines, it will have the ability to generate alot of electricity) on it to maintain position/elevation, so theoretically it could be made mobile.

[freespace]

They can easily distribute the beam over a large area as to make per-square-meter power very low. Focusing the beam is only needed if you have restricted receiver area.

It would also be very easy to detect any miss alignment, and automatically shutdown or realign. There is no need to fear it, if you do, you been reading too many conspiracy theories :P

(note also they would not use the same wavelength which your microwave uses, since the point is to punch through the atmosphere, not cook birds in flight)

1 square km is in geosynchronous orbit, if my maths is right, it would subtend an angle of ((asin(0.5 / 35 786) * 2) / pi) * 180 = 0.00160106688 degrees. I don't think we would have too much to worry about.

[renormalised]

Anything is possible. If it was focused tightly enough to act as a weapon, it would make what we have now look like childish toys. Ol' Ronnie "Raygun" would get his wish:P:D:eyepop:

[renormalised]

Yes they can, and that's what they'd do. But in order to be commercially viable they must maintain a sustainable amount of voltage per square metre in order to pick it up via an antenna. For use as a power source, you'd have to be looking at least 30-50V per square metre. Low enough not to harm anyone, but it'd still give you a bit of a shock...much like a static discharge off a carpet.

What worries people is not so much the potential of beaming large amounts of electricity in a broadcast mode, but what happens if they decide to use a focused beam method of relaying the power down to the ground. Then it doesn't matter what wavelength of microwave they use. They could even use radio waves, but the thing is they'd be carrying tens of thousands of gigawatts of electrical energy all in a tightly focused beam.

The jarheads in the Pentagon could see immediate uses for that kind of beam and none of them are very friendly!!!.

[bmitchell82]

if im not mistaken alot of scientific progression is though these jarheads wanting something to fry somebody else. the way it is i guess. :) least we get rid of the coal burning carbon air conditioners.!

[renormalised]

Yep, that happens to be an unfortunate fact of life...

[Barrykgerdes]

I have what I believe is an article on the original proposal. Made back in the 50's or 60's. I will look it out. It was in Radio and Hobbies. There were pictures and calculations.

I have a full set of R & H on CD but it will take me a little while to look it out.

Barry