Jonathan wrote:

Controversy Flares Over Space-Based Solar Power Plans

Jeremy Hsu
space.com - Wed Dec 2, 10:15 am ET

"Solaren would then need to launch a solar panel array capable
of generating 400 megawatts. The total launch weight of all the
equipment would be the equivalent of about 400 metric tons,
or 20 shuttle-sized launches, according to Hoffert.

1) Energy of a Space Scuttle launch, altitude plus velocity, is no
less than 4.2*10^12 J. $500 million/mission.
2) 20 missions = 9x10^13 J and $10 billion.
3) Solar cell efficiency real world is no better than 20% with
crystalline silicon. 80% bull**** business plan number for RF
conversion, 80% bullh****^2 number for ground recovery.
(0.2)(0.8)(0.8) = 13% orbita; insolation to ground electrical
transfer, assuming absolute perfection. Look up the solar constant
for square mileage of solar cells required.
4) After the power plant delivers 2.5x10^6 kW/hr of electricity it
covers its launch energy. After it delivers another 10^11 kW/hr of
electricity at $0.10/kW/hr net profits, it covers its launch cost.
5) At 400 megawatts 24/7, the bottom of the hole reaches ground
level - assuming no intermediate costs, after 28.52 years (including
leap years).
6) Add in amortization of the cost of materials, maintenannce,
salaries, pensions, healthcare coverage, expense chits... and teh lfie
of a soalr cell installation under solar hard UV, radiation, meteor
showers, and orbital debris. Ground solar cells last about 20 years.
7) If every impossible assumption works dead center double
bullseye, BULL****.

But Solaren says that it would just require four or five heavy-lift
rocket launches capable of carrying 25 metric tons, or about
one fourth of Hoffert's weight estimate. The company is relying
on developing more efficient photovoltaic technology for the
solar panels, as well as mirrors that help focus sunlight.

Solaren has not provided details on just how its technology
works, citing intellectual property concerns. But it expects that
its space solar power can convert to RF energy with greater
than 80 percent efficiency, and expects similar conversion
efficiency for converting the RF energy back to DC
electricity on the ground in California. The company also
anticipates minimal transmission losses from the space
to the ground."
http://news.yahoo.com/s/space/200912...olarpowerplans

The 'inevitable' is steadily becoming possible...imho.

Jonathan

idiot

--
Uncle Al
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(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz4.htm