[ExI] Novel off-planet energy idea

[spike]

> ...On Behalf Of Tom Nowell
> Subject: [ExI] Novel off-planet energy idea
> 
> Currently the most read article on newscientist.com
> 
> http://www.newscientist.com/article/dn19497-outofthisworld-pro
> posal-for-solar-wind-power.html
> 
> and here's an abstract from an astrobiology meeting
> 
> http://www.lpi.usra.edu/meetings/abscicon2010/pdf/5469.pdf
> 
> does anyone know enough astrophysics to guide us armchair 
> space enthusiasts through back-of-the-envelope calculations?
> 
> Tom

Tom there is a mistake in the article, a severe one:

"To draw significant amounts of power Dyson-Harrop satellites rely on the
constant solar wind found high above the ecliptic - the plane defined by the
Earth's orbit around the sun. Consequently, the satellite would lie tens of
millions of kilometres from the Earth."

It would need to be in geosynchrous orbit for any reasonable power
collection scheme I can think of.  If they propose to have multiple
collection facilites and try to aim this transmitter at a moving tartet as
the earth rotates below, my confidence in the whole notion falls over a
cliff. 

That aside, it is too heavy for the amount of power it generates, so it
wouldn't pay back the cost to launch, given present and any likely near term
future heavy lift technology.  I could imagine it if we mine the copper from
the moon, then make a satellite which beams power back to a station on the
moon.  There are very difficult problems there too, because lunar
synrchonous orbit is way out there.  The Lagrange point L1 might work I
suppose.  Getting stuff out there would be crazy expensive.

spike