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Space Solar Collector

Ellipsoid reflector in low solar orbit steers rays to LEO satellite collector
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A nearly-flat (yet ellipsoid) reflector is placed into low orbit around the sun to reflect solar radiation to a collector array in low orbit around the earth. By concentrating the rays with a curved reflector, the energy flux density would be proportional to the square of the ratio of orbits between the earth and reflector. (This could be a huge difference.) The radius of the solar orbit would be chosen based on the maximum service temperature of the reflector. (Tungsten comes to mind.) Many, many safety mechanisms would need to be in place to avoid risk to humans (including a self- destruct for the reflector), but I can still see this as doable.
kevinthenerd, Aug 03 2010


       With Hubble Telescope-like aiming, the rays could be directly sent to a ground station.
kevinthenerd, Aug 03 2010

       For a monthly fee, could this be set up like Satellite Teevee? So, as long as you're a subscriber, the sun rays are directed into your house to heat up the water heater, the stove, that little heating pad people buy for arthritic dogs, etc. Whatever; all that messy distribution minutia can come later! Sounds enormously dangerous and exceedingly unlikely! Proceed directly to the bakery and get to baking, [kevin] old chum, a chilly world awaits your brainchild. Bun! [+]
Grogster, Aug 03 2010

       Oh, one more thing; might this invention be used in defensive or offensive military applications, such as burning down sushi restaurants suspected of harboring evil-doers? Nevermind. I'm already sold.
Grogster, Aug 03 2010

       I'd suggest the limiting factor would be the capability of your collector, not your reflector. An earth orbital concentrating satellite is already reaching the limit of what wer can handle with current technology.   

       Also, like orbital collectors, the economic limiting step is transitioning the power down to the ground. Directly beaming sunlight will bloom like crazy, and be dependent on weather conditions. Microwave beaming or similar is being heavily researched, but no viable solution exists yet.
MechE, Aug 03 2010

       //low orbit around the sun// How do you propose to do that? How you expect to synchronize the solar satellite's ray with the earth satellite's? Is an earth orbit that stays geosynchronous with the sun even possible?
Cedar Park, Aug 03 2010


       Well ... not a true "orbit". If you're prepared to run your propuslion system continuously, you can manage a sort of station keeping ... but basically, no. Not a "free fall" orbit per se.
8th of 7, Aug 03 2010

       You could do an array of satellites around the sun--you'd pretty much have to, because one, as described, just ain't gonna work. And an array isn't much better, really.   

       A mirror satellite will be behind the sun for some of its orbit, on the far side of its orbit, at a bad angle for reflecting, or between the earth and the sun and unable to reflect, almost all of the time.   

       Plus, a reflector close to the sun will see the solar disk as much larger, making it harder to get all the light focussed down into a tight beam.   

       Also, consider this: A workable version of this idea will increase the amount of solar energy hitting the earth. It may be solar power, but it will contribute to global warming.   

       HB-wise, this idea's title is really generic. It could be the name of a category.
baconbrain, Aug 03 2010

       The sun is 8 light minutes away, which means that, once someone on earth started to feel a little warm, it would be 16 minutes before they could do anything about it.
MaxwellBuchanan, Aug 04 2010

       As far as the oribts themselves, that's fairly simple. Polar orbits for both satellites, precessing once per year. It would require a little bit of station keeping, but only a little. The tracking and aiming software is non trivial, as an error of 1.15e-9 degrees is equivalent to a 10 ft misalignment.
MechE, Aug 04 2010

       Good one, [MechE].
baconbrain, Aug 04 2010

       Another point to consider -- although the distance from the sun to the reflector orbiting it will be nearly constant, the distance from that reflector to the earth-orbiting concentrator will be constantly varying.   

       This means that to have an ellipsoidal reflector that focuses the sun's light on the collector requires continuously changing the reflector's geometry.
goldbb, Aug 04 2010


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