Solar-pumped laser power transmission, a way to dramatically decrease launch costs?

"Pat Flannery" wrote
I can't be certain, but I will say that if you move a solar collector
array closer to the sun it will gather more energy for a given size.

You should be certain before you give us your stupid opinion, Pat Flannery.

"Pat Flannery" wrote in message
dakotatelephone...
Androcles wrote:
"Pat Flannery" wrote
I can't be certain, but I will say that if you move a solar collector
array closer to the sun it will gather more energy for a given size.

You should be certain before you give us your stupid opinion, Pat
Flannery.

First of, I didn't write the part you quoted,

Well, zeroth off, I sure as hell didn't write the part you attributed to me
with your stupid snipping. I wonder who did?
You should be certain before you give us your misattributions, Flat Pannery.

Androcles wrote:
"Pat Flannery" wrote
I can't be certain, but I will say that if you move a solar collector
array closer to the sun it will gather more energy for a given size.

You should be certain before you give us your stupid opinion, Pat Flannery.

First of, I didn't write the part you quoted, and second, the Lagrange
points aren't "my stupid opinion", but real points in space that have
been already used to position spacecraft in relation to the Sun and Earth:
http://www.esa.int/esaMI/Operations/SEMM17XJD1E_0.html
The L-1 point will get you around 1/100th closer to the Sun than
something placed in Earth orbit, which isn't much in regards to the
solar power a space array could generate, but in any other place it will
be orbiting the Sun at a different rate than the Earth, meaning the
power transfer distance to the Earth will vary wildly during the solar
collector's orbital period.
Also, a laser that could keep a beam tight enough to fire from the
collector to Earth orbit would be very large, and require a very large
parabolic mirror to refocus it on arrival so that it could be used to
generate electrical power for beaming to Earth's surface; the focusing
mirror could end up being larger than a Earth-orbiting solar power
station, and require a lot higher structural strength (read weight) to
keep it rigid enough not to flex out of shape, so that it can properly
focus the beam to a point.

Pat

Frankly all this seems academic, I haven't seen anything posted that shows
a practical way to convert a laser beam to electricity, unlike a microwave
beam.

?

Dave

"David Spain" wrote in message
...
Frankly all this seems academic, I haven't seen anything posted that shows
a practical way to convert a laser beam to electricity, unlike a microwave
beam.

?

Dave
Actually what you ask for is quite feasible... depending on your definition
of "practical" .
If you have a use for it then I'll do it for you - for my fee, of course.

"Androcles" writes:
If you have a use for it then I'll do it for you - for my fee, of course.

And I have a bridge to sell you, for my fee of course....

;-)

Dave

Pat Flannery writes:

David Spain wrote:
Frankly all this seems academic, I haven't seen anything posted that shows
a practical way to convert a laser beam to electricity, unlike a microwave
beam.

Focus it and use it to heat some sort of working fluid for a boiler and
turbine?

Eh? Why bother with the tertiary conversion? That's even less efficient.
If you need to move the SPS closer to the sun, just enlarge the microwave
antenna on the sat to get a tighter beam.

This would be pretty clunky due to the fairly low efficiency of the laser
converting electrical energy into a beam, although lasers have been built that
convert sunlight straight into a laser beam with no intermediary electrical
step: http://www.technologyreview.com/Energy/19402/

We'll that would make more sense, but you still have to do conversion.

Not convinced.

Dave

David Spain wrote:
Frankly all this seems academic, I haven't seen anything posted that shows
a practical way to convert a laser beam to electricity, unlike a microwave
beam.

Focus it and use it to heat some sort of working fluid for a boiler and
turbine?
This would be pretty clunky due to the fairly low efficiency of the
laser converting electrical energy into a beam, although lasers have
been built that convert sunlight straight into a laser beam with no
intermediary electrical step: http://www.technologyreview.com/Energy/19402/

Pat

"David Spain" wrote in message
...
"Androcles" writes:
If you have a use for it then I'll do it for you - for my fee, of course.

And I have a bridge to sell you, for my fee of course....

;-)

Dave

I do have a use for a bridge, actually. A gentleman by the name of
Wheatstone gave me one.
http://en.wikipedia.org/wiki/Wheatstone_bridge

I could use it to measure the laser generated current for you;
but my fee will be higher than yours, I know what I'm doing.

"Pat Flannery" wrote in message news:C6SdnZo-
Focus it and use it to heat some sort of working fluid for a boiler and
turbine?

Already doing that, dimwit.
http://www.power-technology.com/proj...e-Solar-Tower/