Dale.Amon@H.CS.CMU.EDU (11/01/86)
I find Gary Allen's attack on power sats rather interesting. I should pass
it on to Dr. Glaser; I'm sure he'd get a kick out of it.
A CMU professor was involved with the DOE study on powersats (I'm not
sure he was with the university at that time) and has told me that he
had a very strong dissenting opinion on the report findings. He felt
that the study baselines chosen were chosen with the INTENT to kill
official interest in powersats because DOE had a strong protective
interest in fusion and MHD, and an even stronger bias towards
'soft-tech' wind power, solar cells, solar passive, cogeneration. They
weren't interested in using any baseline scenarios that might make it
look feasible. Remember, this was in the Carter era...
Interestingly enough, powersats were panned by "Mother Jones" at about
the same time in an article that used blantantly falsified information.
I know of one person whose father was misquoted to a point which can
only be called INTENTIONAL.
>From the mumblings I pick up a conferences, it would appear that the
soviets are quite interested in the powersat idea to supply cheap power
for third world client states: a real diplomatic coup for them,
regardless of the front end costs. And of course, once you've built #1,
#2 is a breeze and a hell of a lot cheaper.
There is also strong interest at Astrotech Corporation for building
small powersats for orbital power augmentation. They have some
agreements with Dr. Glaser (Arthur D. Little Corp), who holds US
patents on the powersat idea. The idea is that you start small, make a
buck supplying power for NASA, DOD or whoever, and gradually (over 30-50
years) bootstrap yourself to larger operations, culminating in GSO
stations.
I might add that laser transmission has also been considered as an
alternative means of transmitting power to the surface. The laser
technique is not as well known a quantity. Microwave energy
transmission has been done experimentally over reasonably long distances
with high efficiencies. Actually better than power transmission lines,
and the cost effectiveness gap widens with distance.
Even without GSO powersats, the beaming technology is useful. There
have been proposals to transmit energy from sites where it is cheap (ie
a solar power station in the Sahara) to places where cheap power is
needed (Japan, Western Europe, US) by 'bouncing' it from passive
reflectors in GSO. This might even beat superconducting power lines,
because you don't have to build the infrastructure to get lots of power
to where it is needed. You just tilt the reflector. This is
particularly good for undeveloped countries.
The Soletta is an interesting idea, but I have some misgivings about
the environmental effects of it. Microwaves don't couple directly with
the atmosphere, unless you transmit in the 'waterhole' like your home
microwave ovens. High Power laser transmission could likewise largely
avoid such coupling. But the Soletta will transmit a broad energy band
into an extended region of the atmosphere. The lit oval would
create a warm air mass. I would expect it to set up an elliptically
symmetrical flow with strong updrafts in the center, cool surface winds
sweeping from the surrounding dark areas and a warm high altitude
outflow. If the effects are mild, it'll be great for hang gliders.
I suspect the winds would be quite strong though. Desert areas would be
preferred for such stations because of the dry air. But dry air also
has less heat capacitance and high transmissibility. IE, as soon as it
gets dark in the desert, the air gets cool and the ground radiates it's
heat quickly. Thus we have a boundary temperature differential of
perhaps 40 degrees or more across a boundary of only a few miles. That
strikes me as enough to drive a damn good storm. At the very least, I
would not be the first to fly a 172 anywhere CLOSE to it.
Also due to the desert climate, one would expect such winds to pick up
considerable dust, which as we know from Mars, improves the coupling if
the heating occurs in the updraft rather than the down draft. (Science
10/24/86, "Interannual Variability of Global Dust Storms on Mars") By
the way, I am NOT trying to say that this would cause global dust
storms, only suggesting a possible positive feedback connection that
would cause wider effects than one might at first suppose. It might
continue after daylight, and in fact drift with prevailing weather
systems since it would not be 'locked' in position by an external
energy source. Needless to say, power generation would not be terribly
efficient under such a scenario...
My knowledge of weather dynamics is not that strong, but I wonder about
the impact of coriolis affects. Would such a 60km cell spawn cylconic
storms or other weather anomolies? Could the effects be used to rob
energy from existing cylonic storms? Have we got any atmosphere modelers
out there?