[ExI] Space colonisation plan

[Keith Henson]

On Tue, Sep 25, 2012 at 5:00 AM,  Anders Sandberg <anders at aleph.se> wrote:

> I remember seeing this poster in Max and Natasha's kitchen back in the day:
>
> https://makezineblog.files.wordpress.com/2012/09/space-plan-scan-touched-up-001.pdf

I remember discussing it with Ron Jones when it was new.

> It makes me nostalgic, although not for the typography of the early
> 80's. I suspect that were we to make something similar today (I'm
> looking at you, Keith :-) ) it would look very different, not just in
> content but in topology.

True.

But even in those days Freeman Dyson pointed out that the cost was at
least 100 times to high people to settle space.  Same was true of
power satellites or an attempt to put an industrial base on the moon
or mine asteroids.

But times have changed, and the tiny laser diodes in your DVD player
have grown to where they can power spacecraft (takes GW to get out of
the atmosphere).

I have a paper "Getting Humanity off Fossil Fuels using Space Power
Satellites launched by Laser Powered Rockets"

Abstract:

"Utility-scale ground solar power has a number of problems:
intermittency, large support mass due to gravity and wind, and
transmission cost to distant markets.  Space-based solar power (SBSP)
solves these problems but at the expense of lifting the parts to GEO,
currently around $10,000 per kg.  Beamed-energy rocket propulsion
(lasers), can reduce this cost to under $100/kg at the
500,000-ton-per- year shipment rate by providing substantially higher
exhaust velocity than is possible from chemical fuels.  The lasers (or
redirection mirrors) need to be in GEO for a long acceleration path,
required to keep laser size within practical bounds.  The economic
feedback comes from building an initial power satellite with
conventional rockets, then using the new plant to power propulsion
lasers.  The lasers enable cheap transport from Earth to GEO to
construct hundreds of power satellites and more propulsion lasers.
Power satellites built this way can produce power for half the price
of electricity from coal.  This positive economic feedback is enough
to displace most use of fossil fuel uses in a decade after the first.
They would replace fossil fuels with lower-cost direct electric power
from space and synthetic liquid fuels made from electricity, water and
a source of carbon, even from CO2 out of the air."

That some of you have seen in a much earlier draft.  If you want to
see the current draft, ask.  (Can't post because it is for publication
in the JBIS.)

Keith

PS, really appreciate your and Charles Stross' postings.