[ExI] Peevish legacy of dour Puritanism

[Keith Henson]

I responded to http://www.foreignpolicy.com/articles/2013/01/09/a_new_US_grand_strategy?page=0,7&wp_login_redirect=0

I have read perhaps a couple of hundred articles of this kind in the
last few years.  There is an unspoken underlying assumption based on
the peevish legacy of dour Puritanism.  The future will be tightly
resource limited and we will have to be virtuous, getting by on much
less, moving to tightly packed housing, walking or riding bicycles,
flying seldom if at all and not wasting anything.  (Different rules
for the rich of course.

But speaking of waste, have you ever considered how much of the Sun's
energy is wasted?  Virtually all of it sails by the planets becoming
uselessly dilute.  Why not tap that and quit using fossil carbon?
This question recasts the discussion from "religious like" to
engineering and economics; how do we do it and how do we pay for it?
I am an engineer, so the second part is beyond my remit, but the first
seems to have at least one answer.

Going into space with the technology used to date is like borrowing
money at ruinous interest rates.  It's why the Saturn rockets started
out the size of skyscrapers and came back the size of a mini van.  The
"interest rate" depends on the ratio of the rocket exhaust velocity to
the mission velocity.  We can't do anything about the energy in
chemical rocket fuel, but we can sidestep the problem by using
external heat from a laser.

The result of a long and tedious analysis is that laser propulsion can
get the cost of lifting solar power plants into space down far enough
that energy from space could uncut even coal by a factor of two, and
grow fast enough to end the use of fossil fuels in two decades from
the decision to do it.

Sustainable?  Not really, the Sun will go out in a few billion years.
But it seems like an OK interim solution.

Keith