Orbiting Solar Power Plant Idea

[owensdj]

I was wondering if any scientists have ever talked about putting a satellite in orbit near the sun that would collect solar power and send to the earth? The satellite would be a very large unmanned spaceship that would unfurl huge solar panels to generate electricity 24/7. The energy collected would be sent to earth using lasers. A satellite in earth orbit would use a mirror to direct the laser beam down to a power plant on the surface which would turn the laser beam into heat that would power a conventional power station.

I know it would be very expensive to build and place such a satellite in orbit around the sun, but it seems like it might be worth it to get so much clean, renewable energy. Would it be possible?

 

[xSauronx]

i seem to remember a /. article on this in the last year or two, though i dont remember what brought it up

 

[Howard]

One part of a Dyson swarm?

 

[eigen]

http://en.wikipedia.org/wiki/Solar_power_satellite

 

[EightySix Four]

I had one of those in sim city... then something bad happened, it missed the receptors on earth and toasted my city

 

[PottedMeat]

Heh with that "power for everyone" approach you wont get any funding. I suggest you rephrase your proposal - maybe something like "Death ray will assure complete planetary control" or something.

Seriously though I'm sure people would have issues with what would happen if the thing went off course - ever play SimCity2000? Plus the losses through the atmosphere would probably be quite a bit.

 

[Armitage]

I don't think you'd want the primary in orbit around the sun. It would be orbiting faster then the earth, so you'd have periodic blackouts when it was on the other side of the sun. You could build several to compensate for that I guess. Your relay satellite would likely have to be in geostationary, so that it could send power to fixed site(s) on the ground. Overall, I'm not sure what you get using a heliocentric power satellite and geocentric relay satellite except complexity. Even if you are significantly closer for power generation, you'll just increase your transmission losses getting it back to earth.

 

[everman]

Even if you had a few, there would probably be too much energy loss in the transmission. There's always a dyson sphere or ring world.

 

[eigen]

http://www.spacefuture.com/archive/conc...a_solar_power_satellite_sps_2000.shtml


Read the links I have provided.Or just listen to these guys.

 

[TheoPetro]

What happens when a plane flys through your "transmission lazer" or a bird ??? Do you know how p!ssed PETA would be? .....come to think of it maby itd be a good way to get rid of PETA......wait till there picketing and protesting around the reciever on earth then have a bit of a .....slip :evil: and unfocus the lazer just enough to ..........hmmm the possabilities

 

[bisqeet]

lasers act funny in vacuums, something to do with the dispersion factor. i*d hate to melt the neighbours house by accident.

 

[patentman]

To answer your question, yes, this has been thought of. There are even a few patents that have issued in this area. Most recent idea I've heard in this area involves sending up a satellite into geosynchronous orbit; deploying a huge (like 1 square kilometer) solar cell based on a thin flim of kapton; collecting solar radiation; transforming the solar radiation to microwave radiation, and beaming the microwaves down to a ground station on earth (which consists of a huge dish (again, on the order of 1 sq mile wide)), where the microwaves are converted to conventional electric power and distributed.

We have the tech for most of it. The major flaw thats been pointed out about it is that no one in their right mind would want to be anywhere near that dish. Depending on the microwave frequency selected to transmit from the satellite to earth, the result someone above quoted for sim city might not be too inaccurate.

 

[Noworkia]

Originally posted by: patentman
The major flaw thats been pointed out about it is that no one in their right mind would want to be anywhere near that dish. Depending on the microwave frequency selected to transmit from the satellite to earth, the result someone above quoted for sim city might not be too inaccurate.

I could imagine someone taking control of the "power plant" and using it as a weapon platform.

All your solar collecting satellite are belong to us.

 

[Howard]

Originally posted by: bisqeet
lasers act funny in vacuums, something to do with the dispersion factor. i*d hate to melt the neighbours house by accident.

What lasers are you talking about?

 

[DrPizza]

Alternately, how about

a. Space elevator at the equator
b. Simply plug in the solar panel and run a realllly long extension cord

Space elevators aren't really too far fetched. And, whoever builds the first one pretty much gets to own space, as they can use that elevator to efficiently build more.

 

[Titan]

from an engineering perspective, say we deployed such a generator with a massive solar sail. Wouldn't the photons and other radiation bomarding this thing eventually shift it out of position and then it would float away? I guess it would have to be self powered with particle collectors and thrusters to maintain position.

 

[patentman]

Problem with a space elevator is that there is no known material that is strong enough to support its own weight when stretched from the ground into space. Nanowires are anticipated as being strong enough for this application, but right now they are not a reality.

 

[patentman]

Yeah maybe, but if you anchored the sail from object of substantial mass then it would take a very long time for impacts from solar radiation to move the device out of position. You could easily counteract the impact with some small thrusters

 

[Armitage]

Originally posted by: tkotitan2
from an engineering perspective, say we deployed such a generator with a massive solar sail. Wouldn't the photons and other radiation bomarding this thing eventually shift it out of position and then it would float away? I guess it would have to be self powered with particle collectors and thrusters to maintain position.

Yep - not just the solar radiation pressure, but also the fact that there are only two stable longitudinal locations in geo - everything else will drift toward/oscilate about those positions. You'll also get perturbations in inclination. geostationary satellites typically perform a manuever about every other week to stay within their station keeping boxes.

So yes, but it's not that big a deal.

 

[DrPizza]

Originally posted by: patentman
Problem with a space elevator is that there is no known material that is strong enough to support its own weight when stretched from the ground into space. Nanowires are anticipated as being strong enough for this application, but right now they are not a reality.

Hmmm.... seems I read an article in Discover magazine that they *do* have a material that is strong enough.

 

[Mark R]

Hmmm.... seems I read an article in Discover magazine that they *do* have a material that is strong enough.

But is it strong enough to withstand a hit from a stray decomissioned satellite.

If you were at the top and something severs the rope half way up I would expect the rest of your day to be most unsatisfactory.

 

[klah]

Originally posted by: DrPizza

Originally posted by: patentman
Problem with a space elevator is that there is no known material that is strong enough to support its own weight when stretched from the ground into space. Nanowires are anticipated as being strong enough for this application, but right now they are not a reality.

Hmmm.... seems I read an article in Discover magazine that they *do* have a material that is strong enough.

There was a paper in Science where a group observed a single carbon nanotube under an SEM with a tensile strength of ~63GPa.

Current estimated requirements for a space elevator cable are 60-100+ GPa and 100,000km in length.

MIT created a 100m CN fiber last year, but it wasn't any stronger than a cotton thread.

On a related note Liftport tested their climber up to 305m last week. The say they want to reach 1500m this year.

 

[gsellis]

The idea was around in the 70's and nicknamed PowerSats. A geosync solar array that beamed a microwave beam to a Rectenna (Receive Antenna). The Rectenna was a large area antenna to spread the microwave beam out so that it was not too hazardous to anything flying or moving through it.