[ExI] Alternate to shrinking people

[Keith Henson]

Abstract

Space Transportation in an Era of SBSP

Space based solar power can be used to power transport into space at
remarkably low cost.  Two GW of laser energy beamed down from GEO can
support a traffic flow of 500,000 tons per year at a cost well under
$100/kg.  The front-end cost is high, at $10 per watt, $20 B for 2 GW,
and the cost to lift the first seed laser (500 MW) would be even more,
$25 B at the Falcon Heavy estimated rate.  The investment in
propulsion lasers would pay off in a few years lifting power satellite
parts to GEO.  Diverting only a few percent of power satellite
construction into additional propulsion lasers leads to a traffic flow
in the millions of tons and a rate of power satellite construction
exceeding one TW per year.  Large as the front-end cost is, it makes
sense both in terms of economic return and as a way to reduce military
expenditures, i.e., propulsion lasers on this scale reduce or
eliminate the perceived need to fight wars with emerging nuclear
powers.  Such a program solves energy and carbon problems in addition
to providing energy security for all countries.

^^^^^^^^^^^^^

My presentation to the Alternative Energy NOW conference (full of
military people and the head of strategic planning at ExxonMobil) is
here:

https://docs.google.com/file/d/0Bzm7IoVgps00ZWw0eng4TmRSWkdNWFhpZFk2QzNQUQ/edit

A couple of days later NASA released a 698 page study on beamed energy
propulsion,

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20120002761_2012003334.pdf

Beamed energy propulsion is going main stream.

With enough cheap energy, recycling everything becomes fairly easy.

We could even make fresh water from sea water and pump it inland a
thousand miles for crops.

Keith