Power System: Laser-Based Safer Than Microwave

"EADS Astrium engineers are working on an
orbital solar power concept that they think will
be competitive with other technologies but
safer to use.

Solar power would be collected in space and
beamed to Earth using high-power infrared lasers
so the energy could be used in remote regions,
areas hit by natural disasters and other places
where terrestrial power is not readily available.
Astrium Chief Technical Officer Robert Laine says
the concept offers certain advantages compared to
competing technologies such as microwaves—
notably a much smaller health risk."

See:

http://www.aviationweek.com/aw/gener...e&channel=awst

wrote:

"Solar power would be collected in space and
beamed to Earth using high-power infrared lasers
so the energy could be used in remote regions,
areas hit by natural disasters and other places
where terrestrial power is not readily available.
Astrium Chief Technical Officer Robert Laine says
the concept offers certain advantages compared to
competing technologies such as microwaves—
notably a much smaller health risk."

Oh great, let's replace the maser beam with a heat ray.
Can't we come up with something like "D" cell batteries made from Moon
material with heatshields on them?
(This is _my_ idea Mook; you can't have it!)

Pat

Anyone care to comment on how you get power back out of an IR laser beam?
Are you converting IR laser energy directly to electricity as in the microwave
case, or are you heating something which then indirectly generates electricity
by powering a turbine?

What about atmospheric attenuation and clouds? Or is the IR beam punching through
those clouds?

Size of the beam on the ground?

One of the safety mechanisms I recall about microwave beaming was a proposal that
used a phasing mechanism that caused the beam to focus when a pilot timing signal
was sent up from the ground. Turn off the pilot signal and the beam loses focus
thereby no longer irradiating the ground with high energy microwaves. Could this
be done with an IR laser?

Dave

" (This is _my_ idea Mook; you can't have it!)

Arthur C. Clarke lived to regret not getting patents on ideas others laughed
at.

"David Spain" wrote in message
...
Anyone care to comment on how you get power back out of an IR laser beam?
Are you converting IR laser energy directly to electricity as in the
microwave
case, or are you heating something which then indirectly generates
electricity
by powering a turbine?


From what I've read, microwaves are still the better way of sending
power from orbit. The only use of lasers that I believe is practical
is to use them only through space, to send the power from a collector
to a transmitter, which would convert it to microwaves and send
it to the ground. This way, the power is collected by concentrating
mirrors that collect the energy and turn it directly into lasers.

The huge advantages would be the collectors are a tiny fraction of
the mile-sized solar cell collectors. And the collectors and transmitters
could be in widely different places.

"Val Kraut" writes:

" (This is _my_ idea Mook; you can't have it!)

Arthur C. Clarke lived to regret not getting patents on ideas others laughed
at.

The problem with being a visonary like Clarke is that your ideas outlive the
lifetime of a patent before it can be put into practice. As least as patent
laws existed (in the US) at the time Clarke thought of it. It was a good
20+ years later before it became practical...

http://www.lib.uchicago.edu/e/su/sci/patents.html#Life

Dave

On 31/01/2010 2:29 PM, wrote:
"EADS Astrium engineers are working on an
orbital solar power concept that they think will
be competitive with other technologies but
safer to use.

Solar power would be collected in space and
beamed to Earth using high-power infrared lasers
so the energy could be used in remote regions,
areas hit by natural disasters and other places
where terrestrial power is not readily available.

Where's the commercial demand for power into remote regions hit by
natural disasters?

From a humanitarian point of view, it's a great notion, but it would
never get built on that basis.

Sylvia.