At 01:14 AM 9/5/2008, Kevin wrote:

>Keith,
>I think you have misplaced a comma or two. That is 1.357kW/m2 not 1357
>kW. 1,357Watt/m2  / 4.66 kg/m2 = 291 Watt/kilogram

Unless I don't understand what they are talking about, the article
notes "The 40.8 percent efficiency was measured under concentrated
light of 326 suns."

So the light hitting the cells would be 1.357 kW/m2 x 326 or 442
kW/m2.  Times efficiency that would put out 180 kW/m2.  180
kW/m2/4.66 kg/m2 is 38.7 kW/kg.

>Our thin film cells at 12.4% efficiency rate at 5,880 Watt/kilogram.
>At 2 microns thickness this increases to 16,800 Watts/kg = 16.8 kW/kg.

The trouble with lower efficiency is that the whole power sat is a
lot larger.  This costs you in structure and conductors.  I am not
convinced that photovoltaic cells are the best approach.  They might
be, but steam turbines are extremely well understood and are at least
40% efficient.  If we had a pipeline to lunar or asteroid dirt for
making heat transport fluid, steam would be even more attractive.

>Also there is not much heat sink mass.

True.  A concentration of 326 will require big heat sinks.  But mild
concentration, say 3 especially with some filtering of the parts of
the spectrum that the cells don't use well probably avoids heat sinks.

This is 1400 words of an 8000 word chapter in a novel I was working
on.  The chapter describes the space elevator and building a huge
power sat industry.

*************

The junkyard was attached to the space elevator through the so far
misnamed "driver hubs," a pair of pulleys only a few miles
apart.  Uplift intended to install big electric motors, but the cable
wasn't yet strong enough to lift motors that big in one piece
yet.  UpLift had attached the junkyard to the driver hubs with
breakaway connections in anticipation of the day natural or
artificial space junk cut the cable.  The four quadrants of the
junkyard were minute flower petals on an impossibly long stem.

North and south petals of the junkyard held the local photovoltaic
power sources.  They were small-scale versions of power-satellite
wings and rotated to stay pointed at the sun.  The openings in the
junkyard plane were much larger than the rotating
"wings."  Eventually UpLift would extend them to a GW when they
installed motors on the driver pulleys.

Until recently, when the elevator motors started pushing the power
limits of the Enterprise, there had been tension between building up
the elevator cable and extending the construction facilities.

In the three weeks since Marc had last been up, the fourth
beam-spinner had come on line in the East junkyard.  Ton spools of
perforated 5-mil Invar foil had been shipped up, and after passing
through the beam spinners came out as one meter by 1 km long channel
beams for the power satellites and the junkyard frame.

The same beams went into the frame for power-sat
construction--humorously known as "dry dock."  It had gantries on
both sides that hinged out of the way to launch the power sats to the
east.  The power sats slipped out of dry dock by electrical motors at
6 am local time when the transmitting antenna was in the same plane
as the wings.

The little 60-person inflatable habitat was on the west petal,
pointed north/south with a 45-degree sun-tracking mirror to light
it.  The space for the family habitat was just a large hole in the
junkyard plane further west of the inflatable temporary habitat.

Dry dock was on the east side, pointed north/south and rotating on
bearings to stay pointing 90 degrees from the sun except for a
non-rotating section in the middle for the transmission antenna.  The
antenna pointed down the elevator toward the earth, parallel to the
plane of the junkyard.  The dry dock's rotation kept at 90 degrees
from the sun was so the solar cells could be installed "off."  A
power sat lacked an "off" switch other than turning it away from the
sun.  Inflated white plastic balls on long skinny arms provided light
for the construction crews without generating lethal voltage on the
solar cell arrays.

Power sats were built in the dry dock.  The first, Stubby, was taking
shape as a 1/4 physical scale, 1/5th output power to drive the
elevator in the last stages of the cable buildup.  Stubby would
demonstrate the technology at almost full scale.  Stubby had two
wings like full-scale power sats, but the wings were only two km by
three km instead of five by five km, giving it an overall size of
five and a half km by three km with a one km round transmitting
antenna in the middle.

The bearings, mercury slip rings and transmitting antenna were
installed first, then the two inner end pieces.  The beams were
pulled out of the beam spinners from the outside in, stretched one at
a time, spot-welded to the inner end pieces, then spot welded to the
outer ends.  The beams were placed ten meters apart, a hundred beams
to the kilometer so there were three hundred two-km long main beams
in each wing.  The ton mass of a 1-km beam amused Marc.  In
skyscraper construction, a few meters of beam weighed more than a ton.

The construction process resulted in five flat-bottomed troughs in
each wing connected to a rotating transmitter disk in the middle that
always pointed toward the earth.  Each trough was 600 meters wide,
280 meters high, with 45-degree reflector sides and 200-meter-wide
pavements of solar cells in the middle.  The cells came in rolls, two
meters wide and 200 meters long.  The reflectors raised the light
exposure on the cells to three solars.  A square meter of solar cells
generated only ten volts, but 200 of these in series amounted to
2,000 volts across 200 meters, and five such strips in series
generated 10,000 volts at a scary 100,000 amps from each wing.

Twenty thousand 100-kW klystrons made up the one km antenna and each
of them used ten amps of current.  They came up in hexagonal bundles
of seven and snapped into place.  Two ironworkers could put in a
hundred a day.  There would be 19 to a bundle when UpLift upgraded
the elevator to 2,000 tons a day.
The plans had called for two km long, aluminized-Mylar reflecting
film to be unrolled on the reflectors.  The intent had been to test
the completed power sat in dry dock at full power, then cut it loose
with a number of ion engines to move it into place.

Vacuum degradation around the junkyard and a major flashover/meltdown
on the junkyard's north power wing had the engineers antsy about
powering up a power sat in the construction frame.  To improve the
hardness of the local vacuum, the engineers decided to ship up
uncoated Mylar film and coat the film as it was unrolled with
aluminum.  There is nothing like a fresh vaporized aluminum surface
to absorb stray gas molecules.

Dry dock's first long compression members had been a major pain to
bend.  The ironworkers pulled the beams between the elevator's
unpowered local drive wheels and stretched the beams a few
percent.  That made them straight, but it was hard to get the twist
out.  The ironworkers chopped up the first half dozen and used them
to extend the junkyard.

After some fast design work by UpLift's engineers, they put real-time
controls on the rollers in the beam spinners that bent the flat sheet
into channel beams and put a laser target on the end of the beam to
detect twisting.  The beam spinners then were able compensate for
twisting.  After post-stretching, all of the beams since then had
come out in spec for power sats and most of them were good enough to
carry the dry dock's compressive load where the power sat channel
beams were stretched in place.

Marc's main job this shift was to move the beam spinners along the
start end in the construction frame.  The frame was only three fifths
of its final width and half its length.  When completed and producing
full-sized power sats, the plans called for a thousand beam spinners.

The target construction rate was a power sat every five days, but
that depended on the elevator reaching full capacity, and that
depended on this first quarter scale sat to power it.  Full-scale
power sats would eventually weigh ten thousand tons; Stubby was only
a quarter that mass and bringing up its parts had occupied the
elevator for twenty days.  In addition, it took another twenty days
to bring up the parts for the quarter-sized dry dock needed to assemble it.

When the rolls of beam stock first started coming up, Marc had asked
Floyd why they were not using steel or aluminum instead of this
expensive nickel alloy.
"Eclipses."  Floyd told him.  "For a few weeks around the equinox, an
SPS gets eclipsed by the earth, for up to 70 minutes.  The darn
things cool by 200 hundred degrees; steel or aluminum would curl up
like a potato chip.  Then when the Sun comes back they flap like
wings.  The computer simulations were sad.  We could put hinges and
dampers into them, but using Invar we just ignore eclipses."

There were only 60 people at the construction yard, but they were
critical, taking on jobs such as building and unjamming the
automation.  The speed-of-light delay made it hard to do most jobs
from the ground.

It was amazing how much you could be done in zero-g riding around on
a magnified version of the ancient shuttle arm.  In spite of having
to move the beam spinners around, by the end of Marc's three weeks
they were a quarter done with framing Stubby, having pulled out half
the beams on the north wing.  Four more beam spinners had come up, so
the next quarter would take only half as long.

*******

Keith

>Kevin
>
>
>
>--- In solarpowersatelliteplace@yahoogroups.com, hkhenson
><hkhenson@...> wrote:
> >
> > At 07:22 AM 8/30/2008, you wrote:
> > >Thy these numbers from SpectroLab as well (
> > >http://www.spectrolab.com/DataSheets/Panel/panels.pdf  ):
> > >370 W/m2, mass add-on coverslide needed on these cells for space
> > >launch front side = 1.76 kg/m2 (5.5 mil thick cell), back side 2.06
>kg/m2
> > >(5.5 mil thick cell ). The cells themselves, no mass add-ons are 840
> > >gram per m2.
> > >
> > >  Make these cell 100% efficient and run the numbers again,
> > > theoretical maximum value will be 54% efficient, but for the sake
> > > of argument say 100% efficient.
> > >
> > >0.840 + 1.76 + 2.06 = 4.66 kg/m2
> > >AMO Standard 1,357 m2
> > >
> > >Ouch!
> >
> > I'm sorry, I miss your point here.  What's important is kg/kW.  4.66
> > kg/m2/130kW is only 35 grams/kW.
> >
> > 77,000 m2 of them would only mass 359 tonnes.  That's 3.6% of a
> > 10,000 ton, 5 GWe (ground) power sat.  The reflectors, heat sinks and
> > transmitter are each going to mass way more than these cells.
> >
> > If you are going to this much concentration and big heat sinks I
> > think you might as well just use steam turbines that are already 40%
>efficient.
> >
> > Keith
> >
> >
> >
> > >----- Original Message ----
> > >From: hkhenson <hkhenson@...>
> > >To: solarpowersatelliteplace@yahoogroups.com
> > >Sent: Friday, August 29, 2008 10:00:09 PM
> > >Subject: Re: [Solar Power Satellite Place] NREL Solar Cell Sets
> > >World  Efficiency Record at 40.8 Percent
> > >
> > >
> > >At 05:49 PM 8/29/2008, you wrote:
> > > >FYI,
> > > >
> > > >"NREL Solar Cell Sets World Efficiency Record at 40.8 Percent"
> > > >National Renewable Energy Laboratory
> > > >http://www.nrel. gov/news/ press/2008/ 625.html
> > > >
> > > >: Scientists at the U.S. Department of Energy's National Renewable
> > > >: Energy Laboratory (NREL) have set a world record in solar cell
> > > >: efficiency with a photovoltaic device that converts 40.8 percent of
> > > >: the light that hits it into electricity. This is the highest
> > > >: confirmed efficiency of any photovoltaic device to date.
> > > >
> > > >: The inverted metamorphic triple-junction solar cell was designed,
> > > >: fabricated and independently measured at NREL. The 40.8 percent
> > > >: efficiency was measured under concentrated light of 326 suns. One
> > > >: sun is about the amount of light that typically hits Earth on a
> > > >: sunny day.
> > >
> > >This is interesting.  Let's take a look at some numbers.
> > >
> > >Consider peak sunlight (on the ground) as a kW/m exp 2.  So the
> > >output of a sq meter would be around 130 kW.  I am not sure how to
> > >account for the reflected light from the cell surface.  Ignoring
> > >that, then 60% of 326 kW/m exp 2 will go into heating the
> > >cell.  That's about 195 kW/m exp 2.
> > >
> > >195,000/0.9 = 5.67 x 10 exp -8 T exp 4, T would be almost 1400 deg K
> > >or over 1100 deg C.  Solar cells don't operate that hot so it would
> > >have to be cooled.
> > >
> > >Installed in a power sat and kept well below 100 deg C, it would use
> > >almost as much radiator as a steam turbine system.
> > >
> > >Fewer moving parts though.
> > >
> > >10 GW would require about 77,000 square meters of cell and 23 million
> > >square meters of reflectors or a square close to 5 km on an edge.
> > >
> > >15 GW of waste heat at room temperature would need a radiator of
> > >about the same size, a 5 x 6 km radiator.
> > >
> > >Hmm
> > >
> > >Keith Henson
> > >
> > >
> > >
> > >[Non-text portions of this message have been removed]
> > >
> > >
> > >------------------------------------
> > >
> > >Yahoo! Groups Links
> > >
> > >
> > >
> >
>
>
>
>
>Messages in this topic (3)
>
>
>
>
>
>------------------------------------------------------------------------
>Yahoo! Groups Links
>
>
>
>------------------------------------------------------------------------

Video of press conference here:

http://www.nss.org/news/releases/pc20080912.html

Mankins has performed 2 watt demo over a
distance of 148 kilometres between two islands in Hawaii.

http://blog.wired.com/wiredscience/2008/09/visionary-beams.html

http://www.livescience.com/blogs/2008/09/12/solarsat-power-beaming-
demo-revealed/

Looks like it is included for sale in a DVD here:

http://shopping.discovery.com/product-74197.html?jzid=40588004-66-0

Project Earth DVD Set
#537692 $39.95
Estimated ship date is Nov-07-2008

Product Detail:
Watch as some of the world's leading scientists put the most
ambitious
geo-engineering ideas to the test in order to tackle global climate
change. From covering acres of Greenland's glaciers in protective
blankets to constructing space rockets to sending tiny reflective
lenses into orbit, these experiments push the boundaries of science
and technology by exploring eight creative ideas that just might
reduce global warming.

Experiments include:

Wrapping Greenland
Raining Forests
Infinite Winds
Brighter Earth
Fixing Carbon
Hungry Oceans
Space Sunshield
Orbital Power Plant
See what happens when 'what if' meets 'why not' as Discovery Project
Earth re-engineers the planet's possibilities.

Orbital Power Plant
Premieres Friday, Sept. 12 at 10 p.m. ET/PT.

We could have a source of never-ending power and, at the same time,
reduce our carbon emissions to virtually zero. This is the
astonishing
vision of former NASA physicist John Mankins. He has a plan to send
thousands of satellites into space, which will gather energy from the
sun and then beam the solar energy down to Earth as microwave energy.
The microwave energy will be collected by antennas on the ground.
These then convert the energy to electricity. Can Mankins make it all
work?

It is or will be online here until October 10:
http://video.discovery.com/
I don't know if this episode is up yet. It's called Project Earth:
Orbital Power Plant. You have to jump some hoops (like downloading
their player) to find out.

link to Discovery Channel page where the the "Orbital Power Plant" show
may be watched on-line:

http://dsc.discovery.com/tv/project-earth/project-earth.html  (follow
the link to "episodes" and install the player...)

Please note: the Discovery Channel site may only be watched in the U.S.
where the the program has already been broadcast.

Please digg this article in Washington Post by Ben Bova

http://digg.com/space/Washington_Post_An_Energy_Fix_Written_in_the_Stars
_by_Bova/share

Washington Post: An Energy Fix Written in the Stars (by
Bovawashingtonpost.com — DEAR MR. (FUTURE) PRESIDENT An Energy Fix
Written in the Stars We have a frontier that begins a scant hundred
miles overhead and contains more riches of energy and raw materials
than the entire Earth can provide. Ben Bova is president emeritus of
the National Space Society and the author of nearly 120 nonfiction
books and futuristic novels.

Try this URL if the word wrap is a problem:

  http://is.gd/3Zjb


--- In solarpowersatelliteplace@yahoogroups.com, "Charles F. Radley"
<charles@...> wrote:
>
>
> Please digg this article in Washington Post by Ben Bova
>
>
http://digg.com/space/Washington_Post_An_Energy_Fix_Written_in_the_Stars
> _by_Bova/share
>

FYI,

"An Energy Fix Written in the Stars"
By Ben Bova
Washington Post
http://www.washingtonpost.com/wp-
dyn/content/article/2008/10/10/AR2008101002450.html?sub=new

: You're heading into some rough times as you move into the White
: House, Mr. Future President, what with the economy in recession,
: financial markets in turmoil, global warming, terrorism, war and
: soaring energy prices. But I can offer you a tip for dealing with
: that last issue, at least: Look to the stars.

: That's right. You can use the powerful technology we've forged over
: a half-century of space exploration to solve one major
: down-to-Earth problem -- and become the most popular president
: since John F. Kennedy in the process.

: Right now, the United States is shelling out about $700 billion a
: year for foreign oil. With world demand for energy increasing, gas
: prices will head toward $10 per gallon during your administration
: -- unless you make some meaningful changes. That's where space
: technology can help -- and create new jobs, even whole new
: industries, at the same time.

: You'll have to make some hard choices on energy. Nuclear power
: doesn't emit greenhouse gases, but it has radioactive wastes.
: Hydrogen fuels burn cleanly, but hydrogen is expensive to produce
: and hard to distribute by pipeline. Wind power works in special
: locations, but most people don't want huge, noisy wind turbines in
: their backyards.

: Solar energy is a favorite of environmentalists, but it works only
: when the sun is shining. But that's the trick. There is a place
: where the sun never sets, and a way to use solar energy for power
: generation 24 hours a day, 365 days a year: Put the solar cells in
: space, in high orbits where they'd be in sunshine all the time.

: You do it with the solar power satellite (SPS), a concept invented
: by Peter Glaser in 1968. The idea is simple: You build large
: assemblages of solar cells in space, where they convert sunlight
: into electricity and beam it to receiving stations on the ground.

: The solar power satellite is the ultimate clean energy source. It
: doesn't burn an ounce of fuel. And a single SPS could deliver five
: to 10 gigawatts of energy to the ground continually. Consider that
: the total electrical-generation capacity of the entire state of
: California is 4.4 gigawatts.

: Conservative estimates have shown that an SPS could deliver
: electricity at a cost to the consumer of eight to 10 cents per
: kilowatt hour. That's about the same as costs associated with
: conventional power generation stations. And operating costs would
: drop as more orbital platforms are constructed and the price of
: components, such as solar voltaic cells, is reduced. Solar power
: satellites could lower the average taxpayer's electric bills while
: providing vastly more electricity.

: They would be big -- a mile or more across. Building them in space
: would be a challenge, but not an insurmountable one: We already
: know how to construct the International Space Station, which is
: about the size of a football field. And the SPS doesn't require any
: new inventions. We have the technology at hand.

: Basically, an SPS needs solar voltaic cells to convert sunlight
: into electricity and microwave transmitters to beam the energy to
: the ground. We've been using solar cells to power spacecraft since
: the 1950s. Solar cells are in our pocket calculators, wristwatches
: and other everyday gadgetry. You can buy them over the Internet.
: Microwave transmitters are also a well-developed technology.
: There's one in almost every kitchen in the nation, in the heart of
: our microwave ovens.

: Some people worry about beaming gigawatts of microwave energy to
: the ground. But the microwave beams would be spread over a wide
: area, so they wouldn't be intense enough to harm anyone. Birds
: could fly through the thinly spread beams without harm.
: Nevertheless, it would be best for the receiving stations to be set
: up in unpopulated areas. The deserts of the American Southwest
: would be an ideal location. You could gain votes in Arizona, New
: Mexico, Nevada and California!

: It's ironic, but when solar power satellites become commonplace,
: the desert wastes of the Sahara and the Middle East could become
: important energy centers even after the last drop of oil has been
: pumped out of them. SPS receiving stations could also be built on
: platforms at sea; Japan has already looked into that possibility.

: I admit, solar power satellites won't be cheap. Constructing one
: would cost about as much as building a nuclear power plant: on the
: order of $1 billion. That money, though, needn't come from the
: taxpayers; it could be raised by the private capital market. Oil
: companies invest that kind of money every year in exploring for new
: oil fields. But the risk involved in building an SPS, as with any
: space operation, is considerable, and it could be many years or
: even decades before an investment begins to pay off. So how can we
: get private investors to put their money into solar power
: satellites?

: This nation tackled a similar situation about a century ago, when
: faced with building big hydroelectric dams. Those dams were on the
: cutting edge of technology at the time, and they were risky
: endeavors that required hefty funding. The Hoover Dam, the Grand
: Coulee Dam and others were built with private investment -- backed
: by long-term, low-interest loans guaranteed by the U.S. government.
: They changed the face of the American West, providing irrigation
: water and electrical power that stimulated enormous economic
: growth. Phoenix and Las Vegas wouldn't be on the map except for
: those dams.

: Solar power satellites could be funded through the same sort of
: government-backed loans. Washington has made such loan guarantees
: in the past to help troubled corporations such as Chrysler and
: Lockheed. Why not use the same technique to encourage private
: investment in solar power satellites? If we can bail out Wall
: Street, why not spend a fraction of that money to light up Main
: Street?

: What's more, a vigorous SPS program would provide a viable market
: for private companies, such as SpaceX and Virgin Galactic, that are
: developing rocket launchers. Like most new industries, these
: companies are caught in a conundrum: They need a market that offers
: a payoff, but no market will materialize until they can prove that
: their product works. The fledgling aircraft industry faced this
: dilemma in the 1920s. The federal government helped provide a
: market by giving it contracts to deliver mail by air, which
: eventually led to today's commercial airline industry.

: A vigorous SPS program could provide the market that the newborn
: private space-launch industry needs. And remember, a rocket
: launcher that can put people and payloads into orbit profitably can
: also fly people and cargo across the Earth at hypersonic speed.
: Anywhere on Earth can be less than an hour's flight away. That's a
: market worth trillions of dollars a year.

: It will take foresight and leadership to start a solar power
: satellite program. That's why, Mr. Future President, I believe that
: you should make it NASA's primary goal to build and operate a
: demonstration model SPS, sized to deliver a reasonably impressive
: amount of electrical power -- say, 10 to 100 megawatts -- before
: the end of your second term. Such a demonstration would prove that
: full-scale solar power satellites are achievable. With federal loan
: guarantees, private financing could then take over and build
: satellites that would deliver the gigawatts we need to lower our
: imports of foreign oil and begin to move away from fossil fuels.

: I know that scientists and academics will howl in protest. They
: want to explore the universe and don't care about oil prices or
: building new industries. But remember, they howled against the
: Apollo program, too. They wanted the money for their projects, not
: to send a handful of fighter jocks to the moon. What they failed to
: see was that Apollo produced the technology and the trained teams
: of people that have allowed us to reach every planet in the solar
: system.

: A vigorous SPS program will also produce the infrastructure that
: will send human explorers back to the moon and on to Mars and
: beyond. It could also spur young students' interest in space,
: science and cutting-edge technology.

: Americans are a frontier people at heart. We have a frontier that
: begins a scant hundred miles overhead and contains more riches of
: energy and raw materials than the entire Earth can provide. Mr.
: Future President, if we use these resources wisely, we can assure
: prosperity and peace for the world -- and you have the opportunity
: to write your name in capital letters across the skies.

Mark Reiff

Please digg these two interesting links

Power Beaming Satellite: "One Lightbulb" Experiment

Full link needed for Myspace:

http://digg.com/space/Power_Beaming_Satellite_One_Lightbulb_Experiment

Shortened link good for yahoo etc:

http://snurl.com/4kalt

Solar Satellites Could Beam Gigawatts of Energy from Space

Full link needed for Myspace:

http://digg.com/environment/Solar_Satellites_Could_Beam_Gigawatts_of_E
nergy_from_Space

Shortened link good for yahoo etc:

http://snurl.com/4kamf

The Aerospace Technology Working Group

Ames-NSS Debate Space-based Solar Power (SBSP) Economics - Pete Worden

Space-Based Solar Power - SBSP

Start Time: Tuesday, December 9, 2008 at 8:00am
End Time: Thursday, December 11, 2008 at 5:00pm

Location: NASA Ames Research Center
Street:  Moffett Field
Contact InfoPhone:  2819935629


http://www.acteva.com/booking.cfm?bevaid=165252

Description

http://www.atwg.org/upcoming_workshops.html#agenda

Next ATWG Forum:

Fall 2008 - National Meeting
December 9-11, 2008
NASA Ames Research Center
Sunnyvalle, California

Theme: A New Beginning

Early registration (before November 17, 7PM)
members $235; non-members $285

After November 17, 7PM
members $275; non-members $325

Register for the ATWG
Conference Online

LODGING: Quality Inn & Suites
Lodging has been arranged at the Quality Inn & Suites at 5 Fairchild
Drive in Mountain View, CA (phone 800.544.4444, ID#00059198) from
12-10 through 12-14 where a block of rooms has been set aside. Cost is
$99.99/1 person, $99.99/2 persons, $0.00/extra person charges. Tax:
10.00%. Make you reservations early to insure the block rate.

LODGING: Ames Onsite
A limited number of rooms are available onsite at Ames. For
reservations and information call 650-603-7101.

Hello All,
           The Aerospace Technology Working Group (SBSP Debate),What exactly are
they "Debating"?

There is only 1 business case pending that will work for MW in space testing in
2012,  follow on GW space array manufacturing and deployment 2014 and USA-Canada
energy independence from foreign fuel in 6 years. New Mexico becoming the first
US solar State. This is the Business Plan of Welsom Space Power Consortium and
Space Energy AG (a Swiss Corporation).

There is currently no other game in town, so I am curious what they might be
debating???

No one is the world can make GW scale space solar arrays now and that first
capability arrives in New Mexico concurrent with our in space launch of 1.2 MW
Zia Array and SPS Early Commercial Demonstration of Space Based Solar Power 
demonstrator in 2012.

No one else is attempting to use combined SBSP WPT and rooftop solar farming in
New Mexico (as the first US Solar State) as the forward energy source needed for
underground extraction of 1.7T barrels of known reserves of sand oil in Alberta
Canada enabling a new gross income of $190Trillion (US) for that single SBSP 
project?

I do want Hanger One at AMES/ Moffet Field working with the Navy Research Lab
refitted for Vacuum chamber, plasma interaction, and pre-launch ground test
deployment of 8MW Twin 150-meter European Sail Tower SPS Concept Solar Array
Modules. I think the Navy and local groups plan $25M to save the Historic Land
Mark in any case, might as well be useful to SBSP and High Altitude WPT
Communications Hyperblimps in the bargain. I would personally add 4 MW of thin
film solar panels to the roof of Hanger One, of the same type we will
manufacture in New Mexico at GW scale.

The 8MW Twin Array Modules are the only I see that will fit several on a single
SpaceX Falcon 9 Heavy launch. The Bigelow Inflatable Habitat is the only manned
capable habitat that can fit on a single Falcon 9 Heavy launch with
1.2 MW of Welsom Ultra-lightweight CFRP boom deployment solar sub-arrays and 50
cm DS4G Ion Thrusters that develop 250,000 meters per second Xenon thrust.

How many meters away, how long to the moon anyway at optimal 250,000 m/sec
speeds? What other SBSP demonstrator than the 1.2 MW Zia Array can pay it's own
way at a commercial profit?

The active runway, used now by only Microsoft and other local Silicon Valley
commercial firm is also quite useful at Moffet Field- NASA AMES. Right next to
Microsoft, HP, SUN, Agilent, Intel and IBM, with this pre-launch and testing
facility can not be all bad for SBSP.

Happy Thanksgiving a wrote ( President Lincoln's Executive Order for a National
Day of Atonement and Thanksgiving for God's Mercy and Grace on the USA).
The day of the Grand Dream in a decade has arrived!

Friendly Greetings,

Kevin

Welsom Space Power "The Race is On!"





solarpowersatelliteplace@yahoogroups.com wrote:              Solar Power
Satellite Place - Solar Power Satellite Forum                   Solar Power
Satellite Place - Solar Power Satellite Forum
           Messages In This Digest      (1                Message)
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        The Aerospace Technology Working Group (SBSP Debate), 12/9/2008, 8:0  
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                           The Aerospace Technology Working Group (SBSP Debate),
12/9/2008, 8:0                Posted by:     
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solarpowersatelliteplace@yahoogroups.com                             Tue Nov 25,
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[Non-text portions of this message have been removed]

Please Digg this link:

The Obama-Biden Transition Team looking into Space Based Solar Power.

  http://is.gd/azRf

FYI,

"Wanted! Your Views On America's Space Program Goals"
Space.com
http://news.yahoo.com/s/space/20090113/sc_space/wantedyourviewsonameri
casspaceprogramgoals

: It's time to put your 21st century thinking cap because you've been
: invited to take part in a new study into why the U.S. has a space
: program.

: The new study "Rationale and Goals of the U.S. Civil Space Program"
: is looking for the public's view on the following questions:

: What's the future of human, robotic, commercial, and personal
: spaceflight? Is your life impacted in a meaningful way by the space
: program? What kind of emphasis should the space program represent
: in going forward? How can the country's civil, or non-military,
: space program address key national issues?

: Views - positive or negative - of the general public are welcomed.

: This study is sponsored exclusively by The National Academies, and
: it is not receiving any funds from government agencies or any other
: external sources. The assessment is a joint effort of the Space
: Studies Board and Aeronautics and Space Engineering Board.

: "Specifically, we are anxious to hear a broad range of views from
: the public, including people from outside and inside traditional
: space interest sectors," said Joe Alexander, study director for the
: appraisal. The effort is geared to explore the long-range rationale
: and goals of the civil space program, he told SPACE.com.

: Best objective judgment

: The ad hoc committee will prepare a report to advise the nation on
: key goals and critical issues in 21st century U.S. space policy.
: Furthermore, the committee's to-do list includes:

: - Identifying overarching goals that are important for our national
: interest.

: - Identifying issues that are critically important to achieving
: these goals and ensuring the future progress of the U.S. space
: activities.

: - Discussing options to address unresolved issues.

: - Using its best objective judgment and recognizing other national
: priorities, the committee will explore a possible long term future
: for U.S. space activities that is built upon lessons learned and
: past successes; is based on realistic expectations of future
: resources; and is credible scientifically, technically, and
: politically.

: What to do next?

: First of all, visit the study's Web site.

Rationale and Goals of the U.S. Civil Space Program
A Joint Space Studies Board and Aeronautics and Space Engineering
Board Study
Questionnaire for Public Input
http://www7.nationalacademies.org/ssb/rationale_goals_civil_space.html

Questionnaire
http://www8.nationalacademies.org/survey/deps/ssbcivilspace.htm

: Please provide input by January 30, 2009!

: Once there, you'll find a summary of the study charge, the
: committee roster, and also a questionnaire that can be
: completed and returned to the study group.

: Note: Those wishing to take part are asked to provide their
: input by January 30, 2009!

Mark Reiff

FYI,

"Why Sustainable Power is Unsustainable"
New Scientist
http://www.newscientist.com/article/dn16550-why-sustainable-power-is-
unsustainable.html

: Renewable energy needs to become a lot more renewable – a theme
: that emerged at the Financial Times Energy Conference in London
: this week.

: Supratik Guha of IBM told the conference that sales of silicon
: solar cells are booming, with 2008 being the first year that the
: silicon wafers for solar cells outstripped those used for
: microelectronic devices.

: But although silicon is the most abundant element in the Earth's
: crust after oxygen, it makes relatively inefficient cells that
: struggle to compete with electricity generated from fossil fuels.
: And the most advanced solar-cell technologies rely on much rarer
: materials than silicon.

: Rare metal

: The efficiency of solar cells is measured as a percentage of light
: energy they convert to electricity. Silicon solar cells finally
: reached 25% in late December. But multi-junction solar cells can
: achieve efficiencies greater than 40%.

: Although touted as the future of solar power, those and most other
: multiple-junction cells owe their performance to the rare metal
: indium, which is far from abundant. There are fewer than
: 10 indium-containing minerals, and none present in significant
: deposits – in total the metal accounts for a paltry 0.25 parts per
: million of the Earth's crust.

: Most of the rare and expensive element is used to manufacture LCD
: screens, an industry that has driven indium prices to $1000 per
: kilogram in recent years. Estimates that did not factor in an
: explosion in indium-containing solar panels reckon we have only a
: 10 year supply of it left.

: If power from the Sun is to become a major source of electricity,
: solar panels would have to cover huge areas, making an alternative
: to indium essential.

: Precious platinum

: The dream of the hydrogen economy faces similar challenges, said
: Paul Adcock of UK firm Intelligent Energy.

: A cheap way to generate hydrogen has so far proved elusive. New
: approaches, such as using bacterial enzymes to "split" water, have
: a long way to go before they are commercially viable.

: So far, fuel cells are still the most effective way to turn the gas
: into electricity. But these mostly rely on expensive platinum to
: catalyse the reaction.

: The trouble is, platinum makes indium appear super-abundant. It is
: present in the Earth's crust at just 0.003 parts per billion and is
: priced in $ per gram, not per kilogram. Estimates say that, if the
: 500 million vehicles in use today were fitted with fuel cells, all
: the world's platinum would be exhausted within 15 years.

: Unfortunately platinum-free fuel cells are still a long way from
: the test track. A nickel-catalysed fuel cell developed at Wuhan
: University, China, has a maximum output only around 10% of that a
: platinum catalyst can offer.

: A new approach announced yesterday demonstrates that carbon
: nanotubes could be more effective, as well as cheaper, than
: platinum. But again it will be many years before platinum-free fuel
: cells become a commercial prospect.

: Renewable energy technologies remain the great hope for the future,
: and are guaranteed research funds in the short term. But unless a
: second generation of sustainable energy ideas based on truly
: sustainable resources is established, the renewable light could be
: in danger of dimming.

Mark Reiff

A butterfly’s wing can help us enhancing the solar power
efficiency. Butterfly wings have scales that act as tiny solar
collectors. Researchers from China and Japan are working on designing
more efficient solar cells while taking inspiration from the butterfly
wings. If successful, this discovery may lead to powering homes,
businesses and other applications in the future. Read more at
http://earthalternate.blogspot.com/
<http://earthalternate.blogspot.com/>



[Non-text portions of this message have been removed]

FYI,

"New Company Looks to Produce Space Based Solar Power Within a
Decade"
Universe Today
http://www.universetoday.com/2009/02/18/new-company-looks-to-produce-
space-based-solar-power-within-a-decade

: Is space-based solar power (SBSP) a technology whose time has
: come? The concept and even some of the hardware for harnessing
: energy from the sun with orbiting solar arrays has been around
: for some time. But the biggest challenge for making the concept
: a reality, says entrepreneur Peter Sage of Space Energy, Inc.,
: is that SBSP has never been commercially viable. But that could
: be changing. Space Energy, Inc. has assembled an impressive team
: of scientists, engineers and business people, putting together
: what Sage calls "a rock-solid commercial platform" for their
: company. And given the current looming issues of growing energy
: needs and climate change, Space Energy, Inc. could be in the
: right place at the right time.

: "Although it's a very grandiose vision, it makes total sense,"
: Sage told Universe Today. "This is an inevitable technology;
: it's going to happen. If we can put solar panels in space where
: the sun shines 24 hours a day, if we have a safe way of
: transmitting the energy to Earth and broadcasting it anywhere,
: that is a serious game changer." If everything falls into place
: for this company, they could be producing commercially available
: SBSP within a decade.

: The basic concept of SBSP is having solar cells in space
: collecting energy from sun, then converting the energy into a
: low intensity microwave beam, sending it down to Earth where it
: is collected on a rectenna, and then fed into the power grid to
: provide electricity. Almost 200 million gigawatts of solar
: energy is beamed towards the Earth every second, which is more
: energy than our civilization has used since the dawn of the
: electrical age. We only need a way to harness that energy and
: make it usable.

: Space Energy, Inc.'s vision is to help create an
: energy-independent world, and improve the lives of millions of
: people by bringing a source of safe, clean energy to the planet
: from space. They are looking to become the world's leading, and
: perhaps the first, SBSP enterprise.

: Solar collector beaming energy to Earth. Image courtesy Mafic
: Studios.

: "The biggest challenge for SBSP is making it work on a
: commercial level in terms of bottom line," said Sage, "i.e.,
: putting together a business case that would allow the enormous
: infrastructure costs to be raised, the plan implemented, and
: then electricity sold at a price that is reasonable. I say
: 'reasonable' and not just 'competitive' because we're getting
: into a time where selling energy only on a price basis isn't
: going to be the criteria for purchase."

: Currently, there are times in the US when electricity is sold
: wholesale for close to a dollar a kilowatt during peak usage or
: times of emergency when power needs to be shipped around the
: national grid. Sage said SBSP will never be cost comparable with
: the current going rate of 6 or 7 cents a kilowatt due to the
: enormous set-up costs.

: "We believe we can get it to a reasonable price, a fair market
: price as the demand for energy increases," Sage said.

: A huge energy gap is looming for our world, and that too, will
: change the energy game.

: According to a white paper written by aerospace engineer James
: Michael Snead, "The End of Easy Energy and What Are We Going To
: Do About It," in order to meet the world's projected increase
: in energy needs by 2100 which likely will be at least three
: times what is being produced today, today's sustainable energy
: production must expand by a factor of over 25. Under that
: scenario, even if the US were to build 70 new nuclear plants,
: add the equivalent of 15 more Hoover Dams, expand the
: geothermal capacity by 50 times what it is today, install over
: a million large land or sea wind turbines covering
: 150,000 square miles, build 60,000 square miles of commercial
: solar voltaic farms, and on top of that convert 1.3 billion dry
: tons of food mass to bio fuels, still only 30% of the power
: needs would be filled by 2100, or perhaps even earlier.

: "Looking at every single technology we can as a civilization to
: try and fill the energy gap in a clean and resourceful,
: sustainable way, technologies like SBSP have to be made to
: work," said Sage.

: He says this is an important point. "We're not setting ourselves
: up to compete with coal, or nuclear, or ground based solar or
: wind. I don't want to pick a fight with any of those industries
: saying that we're trying to take a piece of their pie. What
: we're saying is that right now, from a responsible perspective
: in terms of being a good steward for the environment, we need
: to look at every single source of energy that we can get our
: hands on, primarily green, and develop it regardless, because
: we're going to need it. SBSP is one of the few forms of energy
: that has the ability to be base-load, i.e., 24-7, and it's the
: only form of energy that can be broadcast on demand."

: The first phase of Space Energy, Inc.'s plan is to launch a
: small prototype satellite into low Earth orbit. "This will help
: validate the numbers we are speculating on at this point, but
: also validate several different aspects of what SBSP can do,"
: said Sage. "From a successful demonstration, we are hoping to
: close power purchase agreements with one of several entities we
: are in discussions with at present. And on the strength of that
: we should be able to put the first commercial satellite in
: orbit."

: With regards to the timetable, Sage was hesitant to commit to
: a schedule. "As timetables go, everything needs to be flexible,
: but we are looking to close the financing for the demonstrator
: during the first quarter of this year (2009). The demonstrator
: is a 24 to 36 month project and, from there, we will start the
: commercial build-out of the main satellite, which could take up
: to four years to be operational."

: That's an aggressive schedule. But Sage said since their plan
: is being driven from a commercial basis, they can run their
: operation differently than government agencies who don't
: necessarily operate with the bottom line in mind. "Our board
: members and entrepreneurial group certainly have a lot of
: experience running commercial entities. We know what we're
: doing. We're in a market that we hope to pioneer, and everyone
: feels confident that we have what it takes. We certainly have
: the passion, vision and enthusiasm to make this happen."

: What are the biggest hurdles to overcome in this project? "If
: you would have asked me that question a few months ago," Sage
: replied, "I would have said a combination of meeting the right
: people who could understand the vision and scope of what it is
: what we're doing, and raising the initial financing for the
: demonstrator. Those hurdles, at this point, really seem to be
: taken care of. The more we have our technical teams talk with
: investors, the more people understand that we're real and this
: isn't some sort of Star Trek giggle factor. Right now, with the
: level of due diligence that's been done not only on SBSP itself,
: but with ourselves as a commercially viable entity, we're on
: the forefront of many people's agenda in terms of how to move
: this forward. We see a straight path to making this a reality."

: Sage said no new technology is needed for the demonstrator,
: which will be a working, small prototype, but challenges do
: remain to move forward beyond that. "Obviously, there are
: technical challenges because something of this scale has never
: been done before. We know we can do wireless power transmission,
: as NASA did some pretty significant tests on this in the 1970s.
: We know the physics of wireless power transmission, and how
: everything should work from geostationary orbit."

: While the demonstrator won't be of any scale where energy could
: be sold commercially, it would be a proof of concept.

: "Once we've demonstrated that we can wirelessly beam power
: accurately to the ground in a safe, controlled, effective
: manner, and in a way that can be metered and measured," said
: Sage, "we will have taken a massive step forward to prove that
: SBSP is a technology of the future that has the potential to
: really fill a gap in the world's energy needs."

: Some have equated developing SBSP to what was accomplished with
: the Apollo program.

: "There are so many positive spinoffs to SBSP as a game changing
: foundation of space commerce, that just by addressing a lot of
: the challenges that lay ahead, we will be blazing a trail for
: many other opportunities for a low earth orbit economy," Sage
: added.

: Space Energy, Inc. recently attended the World Future Energy
: Summit and has been overwhelmed with the response.

: "We've had discussions with many different entities, both
: governmental and private, in the Middle East; Abu Dhabi,
: United Arab Emirates, Jordan, Dubai, many areas around Europe,
: and many of the world's top investment firms. I don't think
: we're going to be short of people that will want to support
: us." Sage added that in general, SBSP has strong support in
: Washington DC, and that SBSP recently was added to a list of
: technologies being studied by the Obama administration.

: SBSP has ability to literally change the course of history,
: and impact the quality of life for people everywhere. Sage
: said this project is an entrepreneurs' dream.

: "I speak for our entire team here, we're not just focused on
: how much money are we going to make," Sage said. "We're focused
: on the fact that this is an inevitable technology and someone
: is going to do it. Right now we're the best shot. We're also
: focused on the fact that, according to every scenario we've
: analyzed, the world needs space based solar power, and it needs
: it soon, as well as the up-scaling of just about every other
: source of renewable energy that we can get our hands on."

: "Space based solar power will happen whether we crack cold
: fusion, or whether we suddenly go to 80% efficiency on ground
: based solar power (currently its only at 50%)," Sage continued.
: "It has to happen based on the nature on what it is. With that
: in mind, I've been willing to put everything I have on the line
: to be able to make this work, and that was three years, ago. To
: see how far we've come in the past six to eight months has been
: amazing."

: "This is going to happen."

: For more information:

: Space Energy, Inc.
http://www.spaceenergy.com/s/Home.asp

: Space Energy, Inc.'s interactive flash presentation
http://www.spaceenergy.com/Discovery

: Video presentation on Space Based Solar Power by Mafic Studios
http://www.spaceenergy.com/s/DiscoveryPresentation.asp

Mark Reiff

FYI,

: International Symposium on Solar Energy from Space
: September 8-10, 2009
: Ontario Science Centre
: Toronto, Canada
: http://www.spacecanada.org/index.php?page=symposium_on_solar_energy

Mark Reiff

FYI,

"PG&E Makes Deal for Space Solar Power - Utility to buy orbit-generated
electricity from Solaren in 2016, at no risk"
MSNBC
http://www.msnbc.msn.com/id/30198977

: California's biggest energy utility announced a deal Monday to
: purchase 200 megawatts of electricity from a startup company that
: plans to beam the power down to Earth from outer space, beginning
: in 2016.

: San Francisco-based Pacific Gas & Electric said it was seeking
: approval from state regulators for an agreement to purchase power
: over a 15-year period from Solaren Corp., an 8-year-old company
: based in Manhattan Beach, Calif. The agreement was first reported
: in a posting to Next100, a Weblog produced by PG&E.

: Solaren would generate the power using solar panels in Earth orbit
: and convert it to radio-frequency transmissions that would be
: beamed down to a receiving station in Fresno, PG&E said. From
: there, the energy would be converted into electricity and fed into
: PG&E's power grid.

: PG&E is pledging to buy the power at an agreed-upon rate,
: comparable to the rate specified in other agreements for renewable-
: energy purchases, company spokesman Jonathan Marshall said. Neither
: PG&E nor Solaren would say what that rate was, due to the
: proprietary nature of the agreement. However, Marshall emphasized
: that PG&E would make no up-front investment in Solaren's venture.

: "We've been very careful not to bear risk in this," Marshall told
: msnbc.com .

: Solaren's chief executive officer, Gary Spirnak, said the project
: would be the first real-world application of space solar power, a
: technology that has been talked about for decades but never turned into
reality.

: "While a system of this scale and exact configuration has not been
: built, the underlying technology is very mature and is based on
: communications satellite technology," he said in a Q&A posted by
: PG&E. A study drawn up for the Pentagon came to a similar
: conclusion in 2007. However, that study also said the cost of
: satellite-beamed power would likely be significantly higher than
: market rates, at least at first.

: In contrast, Spirnak said Solaren's system would be "competitive
: both in terms of performance and cost with other sources of
: baseload power generation."

: Solaren's director for energy services, Cal Boerman, said he was
: confident his company would be able to deliver the power starting
: in mid-2016, as specified in the agreement. "There are huge
: penalties associated with not performing," he told msnbc.com . He
: said PG&E would be "our first client" but was not expected to be
: the only one.

: The biggest questions surrounding the deal have to do with whether
: Solaren has the wherewithal, the expertise and the regulatory
: support to get a space-based solar power system up and running in
: seven years. "Quite a few hurdles there to leap," Clark Lindsey of
: RLV and Space Transport News observed.

: In the Q&A, Spirnak said his company currently consists of about
: 10 engineers and scientists, and plans to employ more than
: 100 people a year from now. He said each member of the Solaren team
: had at least 20 years of experience in the aerospace industry,
: primarily with Hughes Aircraft Co. and the U.S. Air Force. Spirnak
: himself is a former Air Force spacecraft project engineer with
: experience at Boeing Satellite Systems as well.

: "The impetus for forming Solaren was the convergence of improved
: high-energy conversion devices, heavy-launch vehicle developments,
: and a revolutionary Solaren-patented SSP [space solar power] design
: that is a significant departure from past efforts and makes SSP no
:t only technically but economically viable," Spirnak said.

: Boerman said Solaren's plan called for four or five heavy-lift
: launches that would put the elements of the power-generating
: facility in orbit. Those elements would dock automatically in space
: to create the satellite system. Boerman declined to describe the
: elements in detail but noted that each heavy-lift launch could put
: 25 tons of payload into orbit.

: "We've talked with United Launch Alliance, and gotten an idea of
: what's involved and what the cost is," he said.

: The plan would have to be cleared by the Federal Aviation
: Administration as well as the Federal Communications Commission and
: federal and state safety officials, Boerman said.

: In the nearer term, PG&E's deal would have to be approved by the
: California Public Utilities Commission, Marshall said.

: He said the space-power agreement was part of PG&E's effort to
: forge long-term deals for renewable energy, including deals for
: terrestrial-based solar power. Marshall pointed out that
: space-based and terrestrial-based solar power generation were
: "really very different animals."

: Unlike ground-based solar arrays, space satellites could generate
: power 24 hours a day, unaffected by cloudy weather or Earth's
: day-night cycle. The capacity factor for a ground-based solar is
: typically less than 25 percent. In contrast, the capacity factor
: for a power-generating satellite is expected to be 97 percent,
: Marshall said.

: "The potential for generating much larger amounts of power in space
: for any given area of solar cells makes this a very promising
: opportunity," Marshall said.

: He said the agreement called for 800 gigawatt-hours of electricity
: to be provided during the first year of operation, and
: 1,700 gigawatt-hours for subsequent years. The larger figure is
: roughly equal to the annual consumption of 250,000 average homes.

: PG&E has 5.1 million electric customer accounts and 4.2 million
: natural-gas customer accounts in Northern and Central California.

Mark Reiff

FYI,

"Laser Propulsion: Wild Idea May Finally Shine"
Space.com
http://news.yahoo.com/s/space/20090729/sc_space/laserpropulsionwildideamayfinall\
yshine

: New laser propulsion experiments are throwing light on how to build
: future hypersonic aircraft and beam spacecraft into Earth orbit.

: Indeed, a "Lightcraft revolution" could replace today's commercial
: jet travel. Passengers would be whisked from one side of the planet
: to the other in less than an hour - just enough time to get those
: impenetrable bags of peanuts open. Furthermore, beamed energy
: propulsion can make flight to orbit easy, instead of tenuous and
: dangerous.

: That's the belief of Leik Myrabo an aerospace engineering professor
: at Rensselaer Polytechnic Institute in Troy, NY. He's an expert in
: directed energy applications, aerospace systems, space prime power,
: and advanced propulsion.

: For the past three decades, Myrabo's burning desire has been to
: create and demonstrate viable concepts for non-chemical propulsion
: of future flight vehicles through his research and company
: Lightcraft Technologies, Inc., of Bennington, Vt.

: "Typically, a new propulsion technology takes 25 years to mature...
: to the point where you can actually field it. Well, that time is
: now," Myrabo told SPACE.com.

: Real hardware...real physics

: The brightest new news in beamed energy propulsion is that
: experiments are now underway at the Henry T. Nagamatsu Laboratory
: of Hypersonics and Aerothermodynamics at the IEAv-CTA in Sao Jose
: dos Campos, Brazil.

: The work is being sponsored under international collaboration
: between the United States Air Force Office of Scientific Research
: and the Brazilian Air Force.

: Basic research experiments using high-powered lasers are underway
: in Brazil, with experts investigating the central physics of laser-
: heated airspikes and pulsed laser propulsion engines for future
: ultra-energetic craft.

: At the Brazil-based lab, a hypersonic shock tunnel is linked to two
: pulsed infrared lasers with peak powers reaching the gigawatt range
: - the highest power laser propulsion experiments performed to date,
: Myrabo said.

: "In the lab we're doing full-size engine segment tests for vehicles
: that will revolutionize access to space," Myrabo emphasized. "It's
: real hardware. It's real physics. We're getting real data...and
: it's not paper studies."

: "Right now, we're chasing the data," Myrabo said. "When you fire
: into the engine, it's a real wallop. It sounds like a shotgun going
: off inside the lab. It's really loud."

: The laser propulsion experiments, Myrabo added, are also relevant
: to launching nanosatellites (weighing 1 to 10 kilograms) and
: microsatellites (10 to 100 kilograms) into low Earth orbit.

: Highways of light

: Creating and flying Myrabo's "highways of light" has been a
: methodical and step by step undertaking.

: Back in 1996 through 1999, he flew Lightcraft prototypes via a
: 10 kilowatt high-power infrared laser at White Sands Missile Range
: in New Mexico. In 2000 - sponsored under a grant to his company
: - he established a new world altitude record of over 230 feet
: (71 meters) for laser-boosted vehicles in free fight.

: Myrabo points to his new book "Lightcraft Flight Handbook, LTI-20,"
: co-authored with John Lewis and recently published by Apogee books,
: to explain his quest for low-cost, safe space access with beamed-
: powered Lightcraft.

: "The physics of high-power beamed energy propagation through the
: atmosphere...there's not a lot of expertise out there to make this
: stuff real. It's completely out of the conventional box," Myrabo
: said. "I've been working on it for 30 years. I know how to do it."

: For decades, Myrabo said, what laser propulsion physicists have
: been hungry to achieve is a couple of dollars per watt of laser
: energy. "We're here now. It's a matter of will and do we want to do
: it. This technology is now at the cusp of commercial reality."

Mark Reiff

FYI,

"Mitsubishi, IHI to Join $21 Bln Space Solar Project"
Bloomberg News
http://www.bloomberg.com/apps/news?pid=20601101&sid=aJ529lsdk9HI

: Mitsubishi Electric Corp. and IHI Corp. will join a 2 trillion yen
: ($21 billion) Japanese project intending to build a giant
: solar-power generator in space within three decades and beam
: electricity to earth.

: A research group representing 16 companies, including Mitsubishi
: Heavy Industries Ltd., will spend four years developing technology
: to send electricity without cables in the form of microwaves,
: according to a statement on the trade ministry's Web site today.

: "It sounds like a science-fiction cartoon, but solar power
: generation in space may be a significant alternative energy source
: in the century ahead as fossil fuel disappears," said Kensuke
: Kanekiyo, managing director of the Institute of Energy Economics, a
: government research body.

: Japan is developing the technology for the 1-gigawatt solar
: station, fitted with four square kilometers of solar panels, and
: hopes to have it running in three decades, according to a 15- page
: background document prepared by the trade ministry in August. Being
: in space it will generate power from the sun regardless of weather
: conditions, unlike earth-based solar generators, according to the
: document. One gigawatt is enough to supply about 294,000 average
: Tokyo homes.

: Takashi Imai, a spokesman for the Institute of Unmanned Space
: Experiment Free Flyer, which represents the 16 companies, confirmed
: the selection when reached by phone in Tokyo.

: Far, Far Away

: Transporting panels to the solar station 36,000 kilometers above
: the earth's surface will be prohibitively costly, so Japan has to
: figure out a way to slash expenses to make the solar station
: commercially viable, said Hiroshi Yoshida, Chief Executive Officer
: of Excalibur KK, a Tokyo-based space and defense-policy consulting
: company.

: "These expenses need to be lowered to a hundredth of current
: estimates," Yoshida said by phone from Tokyo.

: The project to generate electricity in space and transmit it to
: earth may cost at least 2 trillion yen, said Koji Umehara, deputy
: director of space development and utilization at the science
: ministry. Launching a single rocket costs about 10 billion yen, he
: said.

: "Humankind will some day need this technology, but it will take a
: long time before we use it," Yoshida said.

: The trade ministry and the Japan Aerospace Exploration Agency,
: which are leading the project, plan to launch a small satellite
: fitted with solar panels in 2015, and test beaming the electricity
: from space through the ionosphere, the outermost layer of the
: earth's atmosphere, according to the trade ministry document. The
: government hopes to have the solar station fully operational in the
: 2030s, it said.

: In the U.S., the National Aeronautics and Space Administration and
: the energy department have spent $80 million over three decades in
: sporadic efforts to study solar generation in space, according to a
: 2007 report by the U.S. National Security Space Office.

Mark Reiff

Followup.

  > > http://hardware.slashdot.org/story/09/09/01/1656246/Japan-Plans-21B-S...

    Sept. 1 (Bloomberg) -- Mitsubishi Electric Corp. and IHI Corp. will
join a 2 trillion yen ($21 billion) Japanese project intending to
build a giant solar-power generator in space within three decades and
beam electricity to earth.

A research group representing 16 companies, including Mitsubishi Heavy
Industries Ltd., will spend four years developing technology to send
electricity without cables in the form of microwaves, according to a
statement on the trade ministry's Web site today.

http://www.bloomberg.com/apps/news?pid=20601101&sid=aJ529lsdk9HI

http://www.bloomberg.com/apps/news?pid=20601080&sid=aF3XI.TvlsJk

I responded on Slashdot.  Here is a copy with additions/deletions.

*************

Tekfactory put his finger squarely on the problem. $500/pound is
close enough to $1000/kg and that is ten times to high for space
based solar power to undercut fossil fuels. The Japanese recognize this.

"Transporting panels to the solar station 36,000 kilometers above the
earth's surface will be prohibitively costly, so Japan has to figure
out a way to slash expenses to make the solar station commercially
viable, said Hiroshi Yoshida, Chief Executive Officer of Excalibur
KK, a Tokyo-based space and defense-policy consulting company. "These
expenses need to be lowered to a hundredth of current estimates,"
Yoshida said by phone from Tokyo.

I get the same number close enough. Current price to GEO $20,000/kg;
required for space based solar power to displace fossils by being
substantially less expensive (1-2 cents per kWh) is $100/kg, a factor of 200.

Design to cost. Start with the rocket equation:

Needed 100 t/hr to GEO, $100/kg. Try a two stage to GEO. Requires 14
km/sec, get the first 4 km/sec with a mass ratio 3 hydrogen/oxygen
rocket. Four km/sec is easy to do, ask Elon Musk. To get the
remaining 10 km/sec with a mass ratio 2 means an average exhaust
velocity of 15km/sec.

Because you stage far short of LEO, the second stage must have
relatively high thrust so ion engines won't do. Ablation laser
propulsion (well understood physics) with an average exhaust velocity
of 15 km/sec will provide over a g at 4 GW. The suborbital path keeps
the second stage out of the atmosphere long enough (15 minutes) for
the laser to push the second stage into geosynchronous transfer orbit.

At 4 payloads an hour (working the laser full time), each payload to
GEO needs to be 25 t. So the mass ratio 2 laser stage is 50 t, the
first stage 50 t (16%structure) and 200 t propellant. On takeoff it
masses 300 tons, less than a 747. A large airport handles a lot more
traffic than eight 747 takeoffs and landings an hour.

Hard engineering and not cheap.  The laser might eventually cost $40
billion. To get started (to positive cash flow) came out to $60
billion on a first cut proforma analysis.

A UK company, Reaction Engines, has an inordinately clever approach
to boost the effective exhaust velocity so as to put payloads (12
tons) into LEO with hydrogen/oxygen single stage to orbit. What they
are doing is recovering a lot of the energy that goes into liquefying
hydrogen and using that to cool and compress air to rocket chamber
pressures up to 26km and Mach 5+. Google for them. Also see
http://www.theoildrum.com/node/5485 if you want more details.

Added new thoughts from the space elevator conference.

A lot of the mass of a thermal power satellite is heat sink
fluid.  That can be made from finely ground rock and a little
gas.  Decouples gas pressure from the amount of heat the pseudo fluid
can carry.  Seems a shame to be shipping up sacks of cement dust.  We
are looking into the payback time for a moving cable space elevator
through L1 to the lunar surface.  Existing materials are good enough
for the cable--without taper.  15 MW is enough to lift 33 tons per
hour.  Feed lunar dirt through a vibratory ball mill and presto heat
sink fluid.

Most of what I have read on the subject suggests converting the solar radiation
to microwave by using photovoltaics and a microwave transmitter. Has there been
much discussion of converting the solar radiation to heat and then re-radiating
this in microwave ?

Below are two paper discussing highly directional radiation from a thermal
source.

http://www.opticsinfobase.org/abstract.cfm?URI=ol-30-19-2623
http://www.nature.com/nature/journal/v416/n6876/full/416061a.html

Here is an abstract:-

"We report the design of a tungsten thermal source with extraordinarily high
directivity in the near infrared, comparable to the directivity of a CO2 laser.
This high directivity is the signature of the long-range correlation of the
electromagnetic field in the source plane. This phenomenon is due to the
resonant thermal excitation of surface-plasmon polaritons."

I would have thought that a solar absorber and a heat pipe connected to a
microwave emitter would be simpler and lighter than going through an electrical
stage.

Pete.

FYI,

"Making Space Power Pay"
MSNBC
http://cosmiclog.msnbc.msn.com/archive/2009/09/18/2075033.aspx

: Power-beaming systems are moving from drawing boards and computer
: slideshow presentations to actual demonstrations on tabletops and
: in exhibit halls. But what will it take to turn power beams into
: profitable outer-space ventures?

: Strangely enough, the challenge of constructing a sheet of
: thin-film solar cells that unfolds to a width of 1,000 feet
: (300 meters) in orbit is not the issue uppermost in the mind of
: William Maness, chief executive officer of Everett, Wash.-based
: PowerSat Corp. The problems that lead his list have more to do with
: earthly affairs - such as getting investors, utilities and
: regulators to buy into the idea.

: Maness told a small gathering at a National Space Society meeting
: in Seattle this week that the pitch for space solar power has been
: directed too often at space enthusiasts who don't have a financial
: stake in the issue, rather than energy utility executives who do.

: "This is one of the reasons why this concept has taken so long to
: start to catch on," he said.

: Maness favors a more market-centered approach to the issue, and
: there are signs that the approach is taking hold. But other signs
: show why the challenge facing Maness and his colleagues in the
: space-power business is so daunting.

: The Solaren story

: First, the positive side: Maness pointed to Solaren Corp.'s deal
: with San Francisco-based Pacific Gas & Eelectric for a 200-megawatt
: space solar power pilot project as a potential success story. "That
: was some brilliant work," he said.

: The deal still must pass regulatory muster, however, beginning with
: approval by California's Public Utilities Commission. Cal Boerman,
: Solaren's director for energy services, told me today that he
: expected the commission to make its decision in October or
: November. The company is also continuing its talks with potential
: launch providers such as United Launch Alliance, Boerman said.

: Solaren's plan calls for sending power-generating satellites, or
: powersats, into space on four Atlas 5 heavy-lift rockets. The
: satellites would convert solar electric power into microwave energy
: for beaming down to a ground station, based within a mile or so of
: the existing power grid. Proximity to the grid is key, Boerman
: said: Neither PG&E nor the PUC wants to put in miles and miles of
: new high-voltage electrical lines to make use of solar-generated
: power.

: The scheme would have to gain approval from the Federal Aviation
: Administration (because of the commercial launches) and the Federal
: Communications Commission (because each powersat is essentially a
: big telecommunication satellite), as well as from all the
: regulatory agencies who have a say in how the ground power station
: is built. Then Solaren would have to put the system into operation
: by 2016, or risk penalties prescribed by its PG&E contract.

: Some say the Solaren deal is a "scam ... pure and simple." One
: scenario suggests that PG&E pursued the deal because it's a no-risk
: way to line up an excuse for falling short of California's
: renewable energy standards ("Gee, we tried our best, but our
: suppliers just couldn't follow through on their promises"). Maness,
: however, thinks that Solaren has displayed enviable business savvy
: so far. He counts the company as a rival to be respected.

: Cost vs. benefit

: Maness' vision for PowerSat would go far beyond Solaren's pilot
: project to put 300 powersats into orbit, forming a constellation
: capable of generating 2,500 megawatts of power. That would be an
: impressive resource, equal to more than a third of Grand Coulee
: Dam's electrical output. The only problem is, right now the
: project's numbers don't add up.

: To be competitive with other power sources, Maness figures that the
: powersat system's launch costs would have to be around $100 per
: pound - which is roughly one-hundredth of the current asking price.
: Launch costs may be heading downward, thanks in part to the rise of
: SpaceX's Falcon rockets, but Maness can't yet predict when the
: charts tracing cost and benefit will cross into the profitable zone.

: For now, Maness is targeting the 2017-2018 time frame for a space
: demonstration project. In the meantime, he's hoping to work through
: a tangle of regulatory issues and also keep an eye on his potential
: competitors - including not only Solaren but also Space Energy
: Inc., Space Island Group, Space Canada and Welsom Space Consortium.

: "It's a race for us right now," Maness said.

: Demonstrations in the works

: Just in the past month there was quite a buzz over reports that
: Japanese companies were planning to join a $21 billion effort to
: set up a powersat system - but it's now clear that those reports
: were overblown.

: The near-term investment is more on the order of $2 million for a
: demonstration of power-beaming technology, Maness said. If the
: technology works successfully in Earth-based tryouts, the Japanese
: plan to launch a test powersat in 2015. But a 1,000-megawatt space
: generating system of the sort mentioned in the initial reports is
: probably two decades down the road.

: Japanese researchers have already made progress in the Earth-based
: demonstration phase: During a powersat symposium conducted this
: month in Toronto, Kobe University researcher Nobuyuki Kaya and his
: colleagues demonstrated an antenna system that could beam enough
: microwave energy across a 30-foot (10-meter) exhibit hall to power
: a small rover.

: Maness has his own earthly demonstrations in the works: At the
: Seattle talk, he showed off a wireless power generator the size of
: a breadbox that transmitted enough power (5 watts) to light up LED
: lights about a foot away. And he has grander plans for building a
: demonstration power beamer mounted on a 20-foot truck, capable of
: transmitting 10 kilowatts over a distance of about 300 yards
: (meters).

: The clock is ticking, however - not only for the powersat market
: but for other energy alternatives as well.

: Terrestrial solar power may have its drawbacks. In addition to
: potential environmental concerns, large-scale solar farms can't
: generate a steady flow of electricity at night, or during cloudy
: weather. But if engineers ever figure out a way to store up the
: intermittent energy generated by solar cells or wind turbines, at
: levels high enough to keep utilities flush with power, Maness
: thinks that would deal a heavy blow to his powersat dreams.

: "At that point, I take my marbles and go home," he said.

Mark Reiff

FYI,

"Power-Beamers Rise Again"
MSNBC
http://cosmiclog.msnbc.msn.com/archive/2009/11/03/2117873.aspx

: Just as one big-money contest for high-tech innovators winds down,
: another revs up: The $2 million Power Beaming Challenge, a
: competition that could lay the groundwork for future space
: elevators, is getting under way - and you can follow the action
: live.

: Like the Northrop Grumman Lunar Lander Challenge, the Power Beaming
: Challenge is part of the NASA-backed Centennial Challenges, a
: program aimed at encouraging new technologies that could be adopted
: by the space agency for future exploration.

: Teams entered in the challenge have been working on robotic
: transport systems that can be remotely powered by laser beams to
: climb up a long steel cable. The contest, part of the Space
: Elevator Games managed by the Spaceward Foundation, started up in
: 2005 and has been getting progressively harder every year.

: This year, the teams will have to get their laser-powered robots to
: zoom up to a height of 1 kilometer  (0.6-mile-long) on a cable
: that's attached to a helicopter hovering above NASA's Dryden
: Research Center in California's Mojave Desert.

: To win the big money, it's not enough just to get up to the top: To
: qualify for a $900,000 prize, your robot would have to maintain an
: average speed of at least 2 meters (6.6 feet) per second. That's
: about as fast as Batman would rise on his super-strong batrope in
: the movies, the Spaceward Foundation's Ben Shelef told me back in
: August. To qualify for an additional $1.1 million, the robot would
: have to go even faster: 5 meters (16.4 feet) per second.

: Can anybody really perform such a feat? Shelef told me today that
: all three of the teams entered in the competition - the Kansas City
: Space Pirates, LaserMotive and the University of Saskatchewan's
: USST team - were technically capable of taking the prize. But the
: challenge could be complicated by other factors, ranging from
: dealing with the wind to keeping the copter in a stable postion, to
: making sure the cable "racetrack" is easily navigable.

: Shelef is hoping that at least one of the teams will end up with
: some money by the time all is said and done. In order for the full
: $2 million to remain in NASA's kitty, "all three teams would have
: to strike out," Shelef said.

: The formula for determining how much money goes to whom under which
: circumstances is rather complicated - and rather than troubling you
: with the math, I'll just point you to the competition handbook.

: Today the organizers are setting up the vertical racetrack and
: planning some dry runs, just to make sure the system will work.
: Shelef told me that "the first money run" will be on Wednesday.

: The Spaceward Foundation came up with the power-beaming contest
: - plus another competition to encourage the development of super-
: strong tether materials - in order to encourage technologies that
: would be needed to build a space elevator to Earth orbit. If such a
: system could be created, it would revolutionize access to outer
: space. But NASA says power-beaming technology would be of use even
: if space elevators are never built.

: If the technology is perfected, it could be used to keep remote-
: controlled rovers moving on the moon or Mars, even in situations
: where sunlight isn't available. Power-beaming also happens to be a
: key technology for transmitting solar power from space. In the
: shorter term, better laser control systems could have military
: applications as well.

Mark Reiff

FYI,

"Success in 'Space Elevator' Competition"
Associated Press
http://news.yahoo.com/s/ap/20091105/ap_on_sc/us_space_elevator

: A robot powered by a ground-based laser beam climbed a long cable
: dangling from a helicopter on Wednesday to qualify for prize money
: in a $2 million competition to test the potential reality of the
: science fiction concept of space elevators.

: The highly technical contest brought teams from Missouri, Alaska
: and Seattle to Rogers Dry Lake in the Mojave Desert, most familiar
: to the public as a space shuttle landing site.

: The contest requires their machines to climb 2,953 feet (nearly
: 1 kilometer) up a cable slung beneath a helicopter hovering nearly
: a mile high.

: LaserMotive's vehicle zipped up to the top in just over four
: minutes and immediately repeated the feat, qualifying for at least
: a $900,000 second-place prize.

: The device, a square of photo voltaic panels about 2 feet by 2 feet
: and topped by a motor structure and thin triangle frame, had failed
: to respond to the laser three times before it was lowered,
: inspected and then hoisted back up by the helicopter for the
: successful tries.

: LaserMotive's two principals, Jordin Kare and Thomas Nugent, said
: they were relieved after two years of work. They said their real
: goal is to develop a business based on the idea of beaming power,
: not the futuristic idea of accessing space via an elevator climbing
: a cable.

: "We both are pretty skeptical of its near-term prospects," Kare
: said of an elevator.

: The contest, however, demonstrates that beaming power works, Nugent
: said.

: "Anybody who needs power in one place and can't run wires to it
: — we'd be able to deliver power," Kare said.

: Earlier out on the lakebed, team member Nick Burrows had pointed
: out how it grips the cable with modified skateboard wheels and the
: laser is aimed with an X Box game controller.

: It had never climbed higher than 80 feet previously, he said.

: The day's competition began late after hours of testing the cable
: system, refueling the helicopter and waits for specific time
: windows in which the lasers can be fired without harming satellites
: passing overhead.

: The Kansas City Space Pirates went first with a machine that
: initially balked but eventually began climbing. Its speed was too
: slow to qualify for any prizes but it got within about 160 feet of
: the top before the laser had to be shut down for satellite
: protection.

: Ben Shelef, CEO of the contest-sponsoring Spaceward Foundation,
: said the Pirates had a minor laser tracking problem but the real
: problem appeared to be in the mechanical system.

: As the afternoon grew late, the University of Saskatchewan's Space
: Design Team had to put off its attempts until Thursday. All three
: teams had further chances to qualify through Friday.

: The competition was five years in the making, Shelef said.

: "A lot of hurdles to cross," he said. "Now that it's happening I'm
: actually happy already. It doesn't matter what the outcome is."

: Funded by a NASA program to explore bold technology, the contest is
: intended to encourage development of a theory that originated in
: the 1960s and was popularized by Arthur C. Clarke's 1979 novel "The
: Fountains of Paradise."

: Space elevators are envisioned as a way to reach space without the
: risk and expense of rockets.

: Instead, electrically powered vehicles would run up and down a
: cable anchored to a ground structure and extending thousands of
: miles up to a mass in geosynchronous orbit — the kind of orbit
: communications satellites are placed in to stay over a fixed spot
: on the Earth.

: Electricity would be supplied through a concept known as "power
: beaming," ground-based lasers pointing up to photo voltaic cells on
: the bottom of the climbing vehicle — something like an upside-down
: solar power system.

: The space elevator competition has not produced a winner in its
: previous three years, but has become increasingly difficult.

: The vehicles must climb at an average speed of 16.4 feet (5 meters)
: per second, or about 11 miles (18 kilometers) per hour, to qualify
: for the top prize. A lesser prize is available for vehicles that
: climb at 2 meters per second.

: The rules allow one team to collect all $2 million or for sums to
: be shared among all three teams depending on their achievements.

: While the concept of an elevator to space may seem too fanciful,
: Andrew Williams, 26, a mechanical engineer on the Saskatchewan
: team, said he has no doubts it will come about.

: "Once we put our minds to something it's just a matter of time for
: us to achieve it," he said.

Mark Reiff

FYI,

"Japan Eyes Solar Station in Space as New Energy Source"
The Age (Australia)
http://www.theage.com.au/technology/sci-tech/japan-eyes-solar-station-in-space-a\
s-new-energy-source-20091109-i50b.html

: It may sound like a sci-fi vision, but Japan's space agency is dead
: serious: by 2030 it wants to collect solar power in space and zap
: it down to Earth, using laser beams or microwaves.

: The government has just picked a group of companies and a team of
: researchers tasked with turning the ambitious, multi-billion-dollar
: dream of unlimited clean energy into reality in coming decades.

: With few energy resources of its own and heavily reliant on oil
: imports, Japan has long been a leader in solar and other renewable
: energies and this year set ambitious greenhouse gas reduction
: targets.

: But Japan's boldest plan to date is the Space Solar Power System
: (SSPS), in which arrays of photovoltaic dishes several square
: kilometres (square miles) in size would hover in geostationary
: orbit outside the Earth's atmosphere.

: "Since solar power is a clean and inexhaustible energy source, we
: believe that this system will be able to help solve the problems of
: energy shortage and global warming," researchers at Mitsubishi
: Heavy Industries, one of the project participants, wrote in a
: report.

: "The sun's rays abound in space."

: The solar cells would capture the solar energy, which is at least
: five times stronger in space than on Earth, and beam it down to the
: ground through clusters of lasers or microwaves.

: These would be collected by gigantic parabolic antennae, likely to
: be located in restricted areas at sea or on dam reservoirs, said
: Tadashige Takiya, a spokesman at the Japan Aerospace Exploration
: Agency (JAXA).

: The researchers are targeting a one gigawatt system, equivalent to
: a medium-sized atomic power plant, that would produce electricity
: at eight yen (cents) per kilowatt-hour, six times cheaper than its
: current cost in Japan.

: The challenge - including transporting the components to space
: - may appear gigantic, but Japan has been pursuing the project
: since 1998, with some 130 researchers studying it under JAXA's
: oversight.

: Last month Japan's Economy and Trade Ministry and the Science
: Ministry took another step toward making the project a reality, by
: selecting several Japanese high-tech giants as participants in the
: project.

: The consortium, named the Institute for Unmanned Space Experiment
: Free Flyer, also includes Mitsubishi Electric, NEC, Fujitsu and
: Sharp.

: The project's roadmap outlined several steps that would need to be
: taken before a full-blown launch in 2030.

: Within several years, "a satellite designed to test the
: transmission by microwave should be put into low orbit with a
: Japanese rocket," said Tatsuhito Fujita, one of the JAXA
: researchers heading the project.

: The next step, expected around 2020, would be to launch and test a
: large flexible photovoltaic structure with 10 megawatt power
: capacity, to be followed by a 250 megawatt prototype.

: This would help evaluate the project's financial viability, say
: officials. The final aim is to produce electricity cheap enough to
: compete with other alternative energy sources.

: JAXA says the transmission technology would be safe but concedes it
: would have to convince the public, which may harbour images of
: laser beams shooting down from the sky, roasting birds or slicing
: up aircraft in mid-air.

: According to a 2004 study by JAXA, the words 'laser' and
: 'microwave' caused the most concern among the 1000 people
: questioned.

Mark Reiff