[ExI] Power satellites

[Keith Henson]

On Thu, Apr 23, 2009 at 8:49 AM, John K Clark <jonkc at bellsouth.net> wrote:
>
> Dan <dan_ust at yahoo.com> wrote:
>
>>> All the numbers on their cost and efficiency are based on speculation.
>
> "Keith Henson" <hkeithhenson at gmail.com>
>
>> No, they are based on utterly sound physics. [...]
>> Capital cost (which I didn't mention)
>
> That is the problem. You keep going on and on about the energy required to
> put a power satellite into geosynchronous orbit but I don't give a hoot in
> hell about that; I'm interested in the dollars required to put it into
> orbit. Not to mention the dollars required to build it.
>
>> isn't entirely speculation either.
>
> Of course it is!

You didn't read what I said: "Because there are other ways to do it,
the capital cost for a
moving cable space elevator can't go over ~$100 billion."

>By honest, if you were a prudent banker would you invest
> hundreds of billions of dollars of your bank's money into Power Satellites
> on the basis of these cost estimates? I wouldn't and I'd take my savings out
> of any bank that did. And you thought investing in sub prime mortgages was
> risky!

I don't know where the money will come from to build power satellites,
or if they will be built at all.  If they are I would bet on it being
Chinese money.

Power satellites and nuclear reactors are the only sources currently
known that scale large enough replace fossil fuels over the few
decades.  The consequences of not replacing fossil fuels are a bit
more serious than the sub prime mortgages, with the models showing the
population of the earth falling to one or two billion people by the
end of this century.

If we could count on the singularity (nanotech and AI) coming in one
or two decades, I wouldn't worry about it.

> The number of large projects that have come in at or under budget could be
> counted on the fingers of one hand, and this thing is larger than any of
> them, and we have no experience to help us because nobody has ever done
> anything even remotely like it before. I'd be very surprise if these cost
> "estimates" (optimistic guesses would be a better word) were accurate within
> 1000%, probably not accurate to 10,000%.

Jordin Kare (who knows far more about laser propulsion than I do)
thinks a billion dollars for a 4-5 MW propulsion laser and one
redirection mirror in GEO would fully demonstrate the transport
system.  It could also clean up space junk at 500 t/year  Given the
seriousness of both energy and space junk, it seems worthwhile.

Did you see the news the the US has committed to spend $60 billion on
a new generation of remotely operated aircraft?

Keith