FYI,

"The Case For Space Based Solar Power Development"
Space Daily
http://www.spacedaily.com/news/ssp-03b.html

: Use of energy, whether fuel for transportation, electrical energy
: running the internet, or the destructive energy released in
: weapons, is central to our economy and security.

: It is with good reason that the technical term for energy use per
: unit time, "power", suggests control in the human world as well.
: Three actions taken now - working to reserve radio spectrum for
: power transmission, focusing on reductions in costs for space
: launch, and investing in space solar power system research - hold
: the promise of opening up vast new sources of power within the next
: 10-15 years.

: Space is big - there is an awful lot of energy out there, and the
: crumbs we fight about here on Earth are laughably tiny in
: comparison. Zettawatts from the Sun pass just through the region
: between Earth and Moon - that's enough energy for each man, woman
: and child in the US to sustainably power an entire US economy all
: to themselves. Even our terrestrial energy choices, fossil or
: renewable, fission or wind, almost all derive from the energy
: profligacy of our Sun and other stars before it.

: Gathering power in space and transmitting it to Earth should not be
: a mystery to us in this 21st century. Communications satellites
: already do it routinely. One significant obstacle to power
: applications, however, is regulatory: there is no spectrum
: allocated to power transmission, as there is for communications.

: Since frequency of operation has a significant impact on
: transmitter design which may alter the design of the overall solar
: power system, the earlier we have a frequency allocation decision,
: the better. The Federal Communications Commission and the
: International Telecommunications Union should be prodded to start
: work on this issue now.

: The potential for power from space has been recognized for over
: thirty years (1). Studies in the late 1970's by NASA and the
: Department of Energy produced a reference design for solar power
: satellites using then-current technology that showed technical
: feasibility, but also high cost. NASA returned to the subject with
: an exploratory study from 1999 to 2001.

: A review by the National Research Council found the program to have
: a credible plan which required significant funding increases.
: Rather than strengthening the program, however, all funding for the
: space solar power group ceased after September 2001, and
: essentially no R&D work on power from space is now being done in
: the US.

: Worldwide over a trillion dollars a year goes to the energy
: industry, and utilities routinely construct multi-billion-dollar
: power plants. The energy industry has a bigger wallet than the
: entire US federal discretionary budget.

: Money is not directly the problem here; profitability is. The two
: essential factors in the cost equation are the cost per delivered
: Watt of the solar power components, and the cost per delivered Watt
: of getting those components to their final destination in space.

: Current costs put the capital investment needed for a space solar
: power system well above the $2/Watt of competitive terrestrial
: options such as fission plants and wind turbines. R&D work is
: needed to bring these costs to where the vast energy resources of
: space are within reach of a large utility project.

: The cost of components is the first problem here. Current prices
: for solar electric power systems are about $2.50 per peak Watt, a
: price that has been declining about 7% per year for the last few
: decades.

: Given the multi-trillion-dollar potential market for space-based
: power, increased funding for launch systems development to
: accelerate these improvements would also be a worthy investment.

: There is another way to reduce launch costs. In David Criswell's
: Lunar Solar Power proposal (5), instead of launching the final
: components from Earth, manufacturing facilities are sent from Earth
: to the Moon to build the solar power system components there. And
: to save even further on launch costs, the solar components stay on
: the Moon and transmit power directly from there.

: Looking at the major cost areas again, for the wholesale utility
: market space solar power is currently about a factor of 2 too
: expensive with regard to cost of materials and components, and at
: least a factor of 10 on the launch cost side. Both cost barriers
: have realistic chances of being overcome in the next decade.

: The prospects for space-based solar power are at least as bright as
: for fusion power; these two options were identified as the only
: long-term sustainable energy sources in a report published in
: Science magazine last year. While space solar power has received
: essentially no government funding for two decades, fusion gets
: close to $1 billion/year.

Mark Reiff