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...100 MW of Space Solar Power ...per single launch!



 
 
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  #1  
Old December 13th 09, 10:41 AM posted to sci.space.policy,sci.space.history,sci.physics
Jonathan
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Posts: 267
Default ...100 MW of Space Solar Power ...per single launch!

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.

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


s




  #2  
Old December 13th 09, 03:37 PM posted to sci.space.policy,sci.space.history,sci.physics
gaetanomarano
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Location: Italy
Posts: 493
Default ...100 MW of Space Solar Power ...per single launch!

..
..

Space Solar Power hoax/illusion DEBUNKED article:

http://www.ghostnasa.com/posts/038sspdebunked.html

..
..

Why the Ares-1 is already DEAD article:

http://www.ghostnasa.com/posts2/058ares1dead.html

..
..
  #3  
Old December 13th 09, 04:20 PM posted to sci.space.policy,sci.space.history,sci.physics
tadchem[_1_]
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Posts: 235
Default ...100 MW of Space Solar Power ...per single launch!

On Dec 13, 4:41*am, "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.

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/20091202/sc_space/controversyflaresover...

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

Jonathan

s


Nice, if there's somebody in orbit who can use 400 MW.

If you want to use it planet-side, you have to get it down here.

THAT creates problems.

A storage device has mass, which brings all the transport problems of
a safe re-entry and recovery.

A conduit would require materials with properties we have not
developed yet.

A beam would present an enormous safety and environmental hazard. You
could cook an Airbus in milliseconds with a 400 megawatt microwave.
That's about 200,000 heavy-duty microwave ovens - at once.

Tom Davidson
Richmond, VA
  #4  
Old December 13th 09, 05:18 PM posted to sci.space.policy,sci.space.history,sci.physics
Peter Fairbrother
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Posts: 100
Default ...100 MW of Space Solar Power ...per single launch!

tadchem wrote:
[..]

Nice, if there's somebody in orbit who can use 400 MW.

If you want to use it planet-side, you have to get it down here.

THAT creates problems.

A storage device has mass, which brings all the transport problems of
a safe re-entry and recovery.


Anti-matter?

A conduit would require materials with properties we have not
developed yet.

A beam would present an enormous safety and environmental hazard. You
could cook an Airbus in milliseconds with a 400 megawatt microwave.
That's about 200,000 heavy-duty microwave ovens - at once.


Not so, actually - an Airbus weighs about 400 tons, call the exposure 1
kW/kg, or perhaps 1 degree C per second, so it would take several
minutes, not milliseconds, before the Airbus might start losing
structural strength. If it was flying rather than parked, the air would
cool it so much that it wouldn't be affected at all.

That's IF you can get it all into the Airbus, which is not even vaguely
likely - a typical ground station covers maybe a square mile, GEO is a
looong way away, and focussing enough energy at that distance to do any
real short-term damage would take a maser, not the typical microwave
transmitter used in these space solar power designs.

The exposure on the ground could easily be low enough to be short-term
survivable for an unshielded human, indeed it would be quite difficult
to get even that amount of power per unit area, and impossible unless it
was deliberately weaponised.

Getting the power down to the ground is tricky, but it's not at all
impossible from a technical or a political viewpoint.


But I don't believe the Solaren numbers on the required uplift mass,
they are too small by a lot, and even if they are correct it has to get
to GEO not LEO (a power station in LEO is pretty much useless), which
would take maybe 60 Shuttle launches, not 20.

At a conservative $100 million per Shuttle launch, that's $6 billion -
and at 10c per kWh it would take 68 years just to recover the launch
costs, ignoring interest - in practice you could never do it.



I don't think Space Solar Power is impossible BTW, but I don't think the
way Solaren are going about it will work, at least not anytime in the
near future.

I'd be looking at a maybe 50 gigawatt system instead, using mirrors,
boilers and turbines - possibly manned. And a much cheaper launch system.

-- Peter Fairbrother
  #5  
Old December 13th 09, 08:43 PM posted to sci.space.policy,sci.space.history,sci.physics
tadchem[_1_]
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Posts: 235
Default ...100 MW of Space Solar Power ...per single launch!

On Dec 13, 11:18*am, Peter Fairbrother wrote:
tadchem wrote:
[..]


Nice, if there's somebody in orbit who can use 400 MW.


If you want to use it planet-side, you have to get it down here.


THAT creates problems.


A storage device has mass, which brings all the transport problems of
a safe re-entry and recovery.


Anti-matter?

A conduit would require materials with properties we have not
developed yet.


A beam would present an enormous safety and environmental hazard. *You
could cook an Airbus in milliseconds with a 400 megawatt microwave.
That's about 200,000 heavy-duty microwave ovens - at once.


Not so, actually - an Airbus weighs about 400 tons, call the exposure 1
kW/kg, or perhaps 1 degree C per second, so it would take several
minutes, not milliseconds, before the Airbus might start losing
structural strength. If it was flying rather than parked, the air would
cool it so much that it wouldn't be affected at all.


How long would the Airbus' avionics last in a 400 megawatt microwave
beam?

You can't fly those crates by the seat-of-the-pants. Knock out the
electronic fly-by-wire systems and the plane becomes a brick.

Tom Davidson
Richmond, VA
  #6  
Old December 13th 09, 08:55 PM posted to sci.space.policy,sci.space.history,sci.physics
Alain Fournier[_2_]
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Posts: 373
Default ...100 MW of Space Solar Power ...per single launch!

tadchem wrote:

On Dec 13, 11:18 am, Peter Fairbrother wrote:


Not so, actually - an Airbus weighs about 400 tons, call the exposure 1
kW/kg, or perhaps 1 degree C per second, so it would take several
minutes, not milliseconds, before the Airbus might start losing
structural strength. If it was flying rather than parked, the air would
cool it so much that it wouldn't be affected at all.



How long would the Airbus' avionics last in a 400 megawatt microwave
beam?

You can't fly those crates by the seat-of-the-pants. Knock out the
electronic fly-by-wire systems and the plane becomes a brick.


As Peter said, a microwave energy beam would be spread over an area
in the square kilometre range. This is not really for security's sake
it is because of basic physics making it impossible to focus a microwave
beam very tightly over long distances. The beam would be survivable
by an unshielded human being (or more likely by a bird flying through
it). The electronics in the jetliner are shielded by the hull of the
plane and will survive the beam even more so than the human wandering
into the beam. This is not a problem.


Alain Fournier
  #7  
Old December 13th 09, 08:57 PM posted to sci.space.policy,sci.space.history,sci.physics
Uncle Al
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Posts: 697
Default ...100 MW of Space Solar Power ...per single launch!

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
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz4.htm
  #8  
Old December 13th 09, 09:02 PM posted to sci.space.policy,sci.space.history,sci.physics
Jorge R. Frank
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Posts: 2,089
Default ...100 MW of Space Solar Power ...per single launch!

Alain Fournier wrote:
tadchem wrote:

On Dec 13, 11:18 am, Peter Fairbrother wrote:


Not so, actually - an Airbus weighs about 400 tons, call the exposure 1
kW/kg, or perhaps 1 degree C per second, so it would take several
minutes, not milliseconds, before the Airbus might start losing
structural strength. If it was flying rather than parked, the air would
cool it so much that it wouldn't be affected at all.



How long would the Airbus' avionics last in a 400 megawatt microwave
beam?

You can't fly those crates by the seat-of-the-pants. Knock out the
electronic fly-by-wire systems and the plane becomes a brick.


As Peter said, a microwave energy beam would be spread over an area
in the square kilometre range. This is not really for security's sake
it is because of basic physics making it impossible to focus a microwave
beam very tightly over long distances. The beam would be survivable
by an unshielded human being (or more likely by a bird flying through
it). The electronics in the jetliner are shielded by the hull of the
plane and will survive the beam even more so than the human wandering
into the beam. This is not a problem.


That's correct. The beam power density will be about one-fourth the
solar constant. Even then, the aircraft hull is a perfect Faraday cage
against the frequencies of the beam.

The safety issues are overblown (the economic issues are not).
  #9  
Old December 13th 09, 11:59 PM posted to sci.space.policy,sci.space.history,sci.physics
eric gisse
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Posts: 342
Default ...100 MW of Space Solar Power ...per single launch!

Jonathan wrote:

[...]

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.


hahahahahahahahahahahahah

If both numbers summed to 10% I would be impressed. Instead I'm insulted for
being lied to so blatantly.

Is the technology 'not existing' an 'intellectual property concern'?

[...]
  #10  
Old December 14th 09, 01:05 AM posted to sci.space.policy,sci.space.history,sci.physics
Sylvia Else
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Posts: 1,063
Default ...100 MW of Space Solar Power ...per single launch!

gaetanomarano wrote:
.
.

Space Solar Power hoax/illusion DEBUNKED article:

http://www.ghostnasa.com/posts/038sspdebunked.html

.
.

Why the Ares-1 is already DEAD article:

http://www.ghostnasa.com/posts2/058ares1dead.html

.
.


Aaagh. More excessive highlighting.

Sylvia.
 




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