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Space Based Solar Power - Printable Version

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Space Based Solar Power - ProjectIon - 12-06-2016

A new article of mine about Space Based Solar Power:

http://blog.the-brights.net/2016/12/05/space-based-solar-power-the-key-to-a-bright-future/#sthash.GdbIzHcQ.dpbs

Thanks,
Adam


RE: Space Based Solar Power - JoeStrout - 12-07-2016

Great article!

I also went and read Maury's article, since he scoffed at your post.  But I don't think your post is scoff-worthy, and I think Maury overstates his conclusions.  He's comparing space solar to pretty much the best possible terrestrial solar — Nevada, and finding that solar cells in Nevada deliver more power over their lifetime by about a factor of 2.

But (1) a factor of 2 isn't always a deal-killer for a system that has other advantages, such as continuous, reliably supply; and (2) this factor of 2 might easily be made up for (or surpassed) by newer solar cell technologies that don't degrade so quickly from radiation damage, as suggested by the thin-film solar cell physicist in his comments.  So, despite Maury's scorn, SBSP is still worth considering.

A couple of thoughts on your piece...


Quote:Practical experiments related to SBSP have taken place, for example in Japan.  This involves the beamed transmission of energy over a distance of over fifty metres.


We've done a lot better than that; in 2008 power was beamed over 92 miles from island to island in Hawaii (reference).


Quote:If SBSP is to move forward, experiments in space are needed to prove the technology involved. An example of this could be a power satellite, somewhat smaller than the eventual structure at only 50 metres in diameter, being placed in geosynchronous orbit and beaming down power to a collecting station on the surface below.

Is that even possible?  My understanding was that antenna size was pretty much dictated by the distance over which you need to transmit (and the spot size you're willing to accept at the receiving end).  I thought this pretty much required km-scale antennas in GEO.

Perhaps a good way to do a smaller-scale demonstration might be a LEO powersat.  It's constantly moving over the surface of the Earth, of course, but you could beam power for a few minutes at a time, making an effective demonstration.

One other idea I've seen (and which we've incorporated into High Frontier) is the use of beamed power in space.  So you have your big powersat in some sunny orbit, with lots of solar panels and the infrastructure to maintain them; and this beams power to space stations and habitats that need it, and want to avoid that extra bulk.


RE: Space Based Solar Power - Pye-rate - 12-09-2016

I agree SBSP would be an optimal supply for many space stations and industries. Solar power articles on some of the tech pages I read material developments are leading to solar panels at about $1 per sq ft and efficiencies of 35-50%. The efficiencies are achieved by multiple color layers each making power from it's part of the spectrum. Durability of cheap solar panels is heading to 20-50 year range. To my mind space to ground solar will not be needed.


RE: Space Based Solar Power - ProjectIon - 12-09-2016

(12-07-2016, 12:19 PM)JoeStrout Wrote:
Quote:If SBSP is to move forward, experiments in space are needed to prove the technology involved. An example of this could be a power satellite, somewhat smaller than the eventual structure at only 50 metres in diameter, being placed in geosynchronous orbit and beaming down power to a collecting station on the surface below.

Is that even possible?  My understanding was that antenna size was pretty much dictated by the distance over which you need to transmit (and the spot size you're willing to accept at the receiving end).  I thought this pretty much required km-scale antennas in GEO.
This is based on the prototype Space Based Solar Power satellite described in this paper: http://enu.kz/repository/2009/AIAA-2009-4897.pdf
The description of the satellite is set out on pages 10 and 11.  I'm perfectly happy to be correct about this if appropriate!


RE: Space Based Solar Power - JoeStrout - 12-09-2016

I guess you're right! A small transmitter like that generates a big spot on the ground — 7 km diameter in this case. But they're proposing to ignore most of that and receive just a portion with a 150 m rectenna for demonstration purposes. Makes sense to me!