[ExI] Doomsday Oil Price: (was RIP: Peak Oil)

[Keith Henson]

There are probably several technical ways out of the energy crisis.

One I have investigated for many years is solar power satellites.
They scale into the tens of TW and the energy payback time (more
useful than EROEI for renewables) is down around two months.  See
http://www.theoildrum.com/node/7898 Power Satellite Energy Economics

"# For the highly reusable Skylon and laser proposal, the laser part,
draws around a GW to send 60 t/h to GEO(starting from a sub orbital
boost by the Skylon).  It also uses 30 ton per hour of hydrogen with
an energy content of 210,000 kWh.  One million, two hundred and ten
kWh/60,000kg is 21 kWh/kg.
# The Skylon boost phase burns 66807 kg of hydrogen per launch; the
energy in the hydrogen (at 70 kWh/kg) for three per hour would be
14,029,470 kWh, / 60,000 kg or 233 kWh/kg.
# Together, 254 kWh/kg, (6% efficient compared to the minimum energy)
so material for a kW of power satellite would take 1270 kWh to
lift--which gives an energy payback time of around 53 days, under two
months."

A more recent version uses four times as much laser power to put the
entire first stage in LEO (solving the problem of getting it back to
the launch point).  Of the 120 ton drop mass, 54 tons gets to LEO, 24
tons reenters and is reused, 20 tons of the 30 ton second stage gets
to GEO and is all used for power sat parts.

So if you can get started, there is no lack of energy to get
completely off fossil fuels.

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.

So who puts up the initial investment?  A big propulsion laser that's
able to track a fast accelerating vehicle from GEO is potentially a
weapon.  It doesn't matter if it is used or not.  After one is up
nobody can count on missiles or aircraft to deliver packages that go
_FLASH_.  And the justification for sorting atoms by mass goes away
because nuclear reactors are under priced by 2 cent per kWh power from
space.

Some will argue that it would give the US (or China) a weapon they
could use to kill people anywhere, anytime.  So how does this differ
from Predator drones loaded with Hellfire missiles?

$50 B is big for a private investment, but it's small change for a war
and on a par with what the US spent for the F-22.

Keith