[ExI] Small solar satellites

[Adrian Tymes]

On Sat, Feb 25, 2012 at 11:10 AM, Keith Henson <hkeithhenson at gmail.com> wrote:
> The problem is the initial investment, $50-100 B.  One concept is to
> use 250 Falcon Heavy launches to put a half GW propulsion laser seed
> in GEO and use 1/4 scale (30 tons) air launched vehicles to bootstrap
> the rest of the 2 GW needed to support a 500,000 ton per year parts
> pipeline to GEO.  That only builds ~100 GW of new power per year, but
> the profit is such it can rapidly grow by a factor of 10-20.  There is
> room in GEO for ten times the current total energy use of humans.

Ah, right!  Keith, this is something I wanted to ask you about re: one of
the research groups I've gotten involved with.

In short, what would the economics of this look like, if you broke it into
~1 kg sized launches?  Specifically: 1 CubeSat launched at a time to
LEO, to contain boosters to put a sub-kg power satellite into GEO.
Just keep feeding more of these over time, making a cluster - both to
easily replace any part that fails, and to let you get started for a far
smaller investment.

Key questions:

* How many satellites would you need to get any measurable output
at ground side?  Not enough to export useful energy, but enough to
demonstrate "ground truth" that the system works.  This is an
important milestone for many would-be investors - even for systems
where there is no theoretical question as to feasibility.  (You're proving
that whoever did this, either has or knows how to get the necessary
resources - people, materials, regulatory approval, et cetera.)

* How much energy would you get from this minimal version, and how
would it scale by adding more satellites?  Linearly?

* What's the minimum size of ground side receiving station that you
would need?

* Would the minimum size of ground side station scale linearly with
the number of satellites?

* What would the initial investment to cover manufacture, assembly,
and installation of those components (and anything else necessary
for a minimum ground truth version)?