I have run into this issue as well and have been
putting forth this solution. Please let me know it is
actually representative of something and not pure
fiction.

Being fully mindful of the disaster of public opinion
regarding nuclear power, I figured it was near
impossible to defend beaming gigawatts of microwaves
at any frequency to earth where it might impact the
health of people or wildlife. A quick check of the
globe yielded three other places that look a lot more
appealing namely the Sahara desert, Tibetan Plateau,
and floating in the middle of the Pacific Ocean
anchored to an island atoll. This gets completely
around the sensitivities of the Western governments in
regard to their territory and gets a revenue flow
started that will make the next step possible.

The next step to me was building a very large wall
around the receiver (some 50 km in diameter for a
satellite in GSO) that is high enough to prevent birds
or anything else from flying over it. This would
prevent any problems at higher energies due to bird
kill. Unfortunately you have to go to something like
10 feet off of the ground to do this completely but
nobody is likely to care in the Sahara if this is not
done immediately.

The last was to either lower the orbital height of the
satellites or increase the size of the receiver until
there was essentially no spillover of microwave
energy. Once you have a revenue stream and the
electricity to power metal production the cost of
building such structures comes down to reality pretty
fast.

- Thor Olson

Arthur P. Smith wrote,

"
the
last complaint that I never got around to responding
to was that the
whole scheme was impractical because the beamed
microwaves would swamp
out huge bands of Earth wireless telecommunication
capacity...
"

I don't have the background to be able to evaluate
whether or not that is
a legitimate concern. Does anyone care to enlighten
us on this topic?

Ron

It might have helped to do some more reading on SPS first. WRT location: One of the chief benefits of SPS over things like ground-based solar, wind, geothermal, and water power is that it isn't geography-bound. The ability to beam power to wherever the markets are is a plus. WRT walls to keep out birds: Birds would suffer no ill effect from flying though an SPS beam. This was confirmed in DOE experiments conducted in the 70's. No need for the expense of several-miles-long walls. WRT lowering the satellite or enlarging the rectenna: There have been more recent proposals for LEO SPS (more for reasons of reducing lift costs than narrowing the beam). But this kills one of the chief advantages of the original SPS designs which is the geostationary position, in a region of space which is rarely eclipsed. As for enlarging the antenna, the existing designs have already been sized for taking in the primary lobe, and 1 or 2 secondary lobes. Those further lobes spilling off the edge are negligible. I think a problem we face is that even people favorably disposed toward SPS still don't appreciate the extent to which most of the problems have already been solved. Like Arthur P. Smith said, we need to do a better job of spreading the word.
Regards,
Mike Combs

putting forth this solution. Please let me know it is
actually representative of something and not pure
fiction.

Being fully mindful of the disaster of public opinion
regarding nuclear power, I figured it was near
impossible to defend beaming gigawatts of microwaves
at any frequency to earth where it might impact the
health of people or wildlife. A quick check of the
globe yielded three other places that look a lot more
appealing namely the Sahara desert, Tibetan Plateau,
and floating in the middle of the Pacific Ocean
anchored to an island atoll. This gets completely
around the sensitivities of the Western governments in
regard to their territory and gets a revenue flow
started that will make the next step possible.

The next step to me was building a very large wall
around the receiver (some 50 km in diameter for a
satellite in GSO) that is high enough to prevent birds
or anything else from flying over it. This would
prevent any problems at higher energies due to bird
kill. Unfortunately you have to go to something like
10 feet off of the ground to do this completely but
nobody is likely to care in the Sahara if this is not
done immediately.

The last was to either lower the orbital height of the
satellites or increase the size of the receiver until
there was essentially no spillover of microwave
energy. Once you have a revenue stream and the
electricity to power metal production the cost of
building such structures comes down to reality pretty
fast.

- Thor Olson

problem

> WRT lowering the satellite or enlarging the rectenna: There have been more
> recent proposals for LEO SPS (more for reasons of reducing lift costs than
> narrowing the beam). But this kills one of the chief advantages of the
> original SPS designs which is the geostationary position, in a region of
> space which is rarely eclipsed. As for enlarging the antenna, the
existing
> designs have already been sized for taking in the primary lobe, and 1 or 2
> secondary lobes. Those further lobes spilling off the edge are
negligible.

Well... I think that in theory a LEO network of satellites could still
provide beamed energy in a 24/7 basis, like geostationary SPS, but they
would have to be SPS *and* microwave receiver power stations. They could
form a dynamic net of beamed energy where the satellites in the light side
beam energy to the ones in the dark side, and those beam the energy to parts
of Earth during the night. But that would enormously enlarge the complexity
(and cost, I think) of the system, and it would also waste much of the
energy.

Besides, I can't see why a similar system couldn't be done (in a much
simpler and cheaper way) with high-altitude balloons at fixed positions.

> Regards,

Regards,

> Mike Combs

Lucio Coelho

> I have run into this issue as well and have been
> putting forth this solution. Please let me know it is
> actually representative of something and not pure
> fiction.
>
> Being fully mindful of the disaster of public opinion
> regarding nuclear power, I figured it was near
> impossible to defend beaming gigawatts of microwaves
> at any frequency to earth where it might impact the
> health of people or wildlife.

I think it depends on the scientific sophistication of your
audience. Sure, there'd be gigawatts of MW energy beaming down to
the rectenna, but there'd be be more than twice the gigawattage of
sun energy beaming down on to the rectenna farm.

Nobody seems to concerned about the sun energy, so to put it in
perspective, we'd be adding only half again as much energy to the 10
km diameter of the the rectenna farm.

A quick check of the
> globe yielded three other places that look a lot more
> appealing namely the Sahara desert, Tibetan Plateau,
> and floating in the middle of the Pacific Ocean
> anchored to an island atoll.

You'd have massive transmission loss having to move that electricity
through wires that are thousands of miles long.

This gets completely
> around the sensitivities of the Western governments in
> regard to their territory and gets a revenue flow
> started that will make the next step possible.
>
> The next step to me was building a very large wall
> around the receiver (some 50 km in diameter for a
> satellite in GSO) that is high enough to prevent birds
> or anything else from flying over it. This would
> prevent any problems at higher energies due to bird
> kill.

Birds might get a little warmer flying through the 10 km beam
footprint, but it would be akin to comparing the intensity of
sunlight at Montreal or Berlin, to the Sahara or Mojave deserts.
Birds seem to do fine even in the hotter climates.

No, I don't think we'll be seeing Kentucky Fried Chicken salvage
vans picking up fried birds from the ground :)

Unfortunately you have to go to something like
> 10 feet off of the ground to do this completely but
> nobody is likely to care in the Sahara if this is not
> done immediately.
>
> The last was to either lower the orbital height of the
> satellites or increase the size of the receiver until
> there was essentially no spillover of microwave
> energy. Once you have a revenue stream and the
> electricity to power metal production the cost of
> building such structures comes down to reality pretty
> fast.
>
> - Thor Olson

I agree with Mike Combs comments with respect to the above.

I glad you've joined the list and you seem enthusiastic about the
SPS concept and you clearly recognize its elegance.

I'd suggest you pick up a copy of "The High Frontier" by O'Neill,
or "Colonies in Space" by Heppenheimer. Both books go into a lot of
detail about SPS.

Further, I learned alot by working my way through the archive of
this list. Took a bit of time, but it was enlightening.

Welcome,

TangoMan