[ExI] pentagon wants orbiting solar power stations

[hkhenson]

At 07:21 PM 10/16/2007, Jeff Davis wrote:
>On 10/16/07, David Lubkin <extropy at unreasonable.com> wrote:
>
> > I am surprised that none of the tech rich who are putting
> > money in space are talking about asteroids. Maybe (he hoped) they're
> > working on it, but quietly.
>
>Or maybe they just don't think it's a reality-based project.  To be
>tech rich might imply feet firmly on the ground.

It's the same exact problem space colonies/SPS had clear back in the 
1970s.  Human minds just stall out when the number of step to get to 
a goal exceed some smallish number.  That might be correct.  When you 
stack enough tasks in series, each one of which has a significant (or 
unknown) chance of failing, the whole thing just gets to be impossible looking.

>Also, what kind of profitability are we talking about here?  What kind
>of Stuff do you go after first?

One metric Eric Drexler used was the time for a machine to process 
it's own weight in material.  Vapor deposit metal boilers could 
vaporize their own mass in iron in 8 hours.  ~1000 times per year.

If you were processing a iron/nickel asteroid for 1 ppm gold with 
such a plant, a tonne of processing plant would process 1000 tonnes 
of asteroid a year--giving you a kg of gold for your trouble--which 
at today's price is in the range of $24,000.

Of course you could also get 100 tonnes of nickel, which at $50,000 
mt would be worth $5 million--if you could get it back to a market.

In both cases, space based production would probably break the market 
from a few plants starting up and prices would fall to 1/1000 times 
the present value.

At 2kg/kW and $0.10/ kWh, a tonne of SPS parts delivered to GEO will 
return about $440 a year in electricity sales, with this income 
stream perhaps falling to $50 per tonne per year over a decade or so.

>Surely it's got to be something more
>valuable that a hunk of iron/nickel.  You know, something like  gold,
>platinum, palladium, tungsten.  With all that stuff broken up into
>chunks, what exactly would be considered "the motherload"?

There are lots of things to make money on, but I expect that the 
demand for such materials will dry up about the time the plants come on line.

Keith Henson

PS.  You probably want to use the 
http://en.wikipedia.org/wiki/Mond_process, to process nickel/iron asteroids.