[ExI] Gigideath was aboriginal humans

Keith Henson hkeithhenson at gmail.com
Tue Mar 25 14:18:30 UTC 2008


On Mon, Mar 24, 2008 at 3:14 PM, The Avantguardian
<avantguardian2020 at yahoo.com> wrote:
> --- hkhenson <hkhenson at rogers.com> wrote:
>
>  > As some of you know, I have been working on a pre singularity
>  > solution to the energy problems (power sats).  Unfortunately, my
>  > efforts are not likely to accomplish much.
>
>  Is there is some reason other than fear-based politics that we cannot
>  further increase our reliance on nuclear energy until we can get power
>  sats online?

How about fear based reality?

http://www.kuro5hin.org/story/2007/10/30/18253/301

The problem is that the US scattered DU around the mid east without a
thought that you can make high grade plutonium out of it in any
reactor.

>  If I remember your detailed series of posts on the topics,
>  the largest piece of unobtainium that made your proposal impractical
>  was the space elevator, the design of which took up the majority of
>  your description. Can you give some details regarding the actual power
>  sats themselves. More specifically things like mass, materials, costs,
>  number, etc.

There were a number of detailed studies of power sats back in the late
70s.  The mass number currently on Wikipedia is 2kg/kW.  Anything less
than 3kg/kW pays back the energy need to lift it to GEO in a day or
less using mechanical power.  As to cost, the are currently utterly
dominated by the cost of lift to GEO by rockets.  As to number, if you
want to put a dent in the energy problem, it's in the range of 300
GW/year installed.  At 5 GW each, that's 60 of them, or 600,000 tons
per year to GEO.

The unobtainium part of the space elevator is the cable.  There are
persistent rumors that the University of Cambridge has demonstrated 20
GPa nanotube yarn, the report has been expected to be published in
science for a few months, but nothing has happened.  Even 20 GPa isn't
strong enough, but it's getting there.

>  If you make these power sats contigent on a space elevator, then we
>  probably are screwed. But if we can at least some power sats into
>  orbit, it may help us bootstrap a space elevator later.
>
If we can set up a 600,000 ton per year pipeline into space with
rockets or laser launchers, that's probably the way to go.  You have
to dedicate the first 15-20 power sats to powering the lasers or
making rocket fuel, but after they are in place, the project is a net
generator of energy at a high enough rate to replace coal and oil.

If you wonder why an old L5 guy does not promote extra terrestrial
materials, it's because of time.  The singularity will come before
space industry to process them can be set up.

Keith



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