Interview with Eric Kotani
By: Mark McCormick
The sci-fi adventure novel The Legacy of Prometheus by Eric Kotani  and John Maddox Roberts
told of global energy woes and a quest to launch a Solar Power Satellite (SPS) that collects energy
from the sun and beams it back to earth using microwaves. That notion, once only science fiction,
may soon become a reality. The U.S. Department of Defense is strongly concerned about the
national security implications of dependence on foreign oil in the face of market competition from
China and other developing nations. Solar Power Satellites are seen as a possible solution and one
that doesn’t generate other problems, such as toxic waste or green house gases. Air Force Lt. Col.
Michael “Coyote” Smith of the National Security Space Office is advocating a small demonstration
SPS to demonstrate beaming power from a geostationary orbit within the next eight to ten years.

Eric Kotani has authored and co-authored many science fiction novels including The Legacy of
Prometheus (with John Maddox Roberts) and Star Trek Voyager17, Death of a Neutron Star. He
edited Requiem: New Collected Works by Robert A. Heinlein and Tributes to the Grand Master. For
many years, he was also a judge for the Writers of the Future contest.

Unlike many fiction writers, Mr. Kotani is eminently qualified to write about advanced scientific
concepts. Eric Kotani is the pen name of NASA Astrophysicist Yoji Kondo, Ph.D. He was head of the
astrophysics laboratory at NASA Johnson Space center during the Apollo and Skylab Missions, and
was the director of a geosynchronous satellite observatory for 15 years. He is a recipient of NASA
Medal for Exceptional Scientific Achievement and also of the Isaac Asimov Memorial Award for
significant contribution to the public understanding of science through writing. An asteroid (8072)
was named for Dr. Kondo in recognition of his contributions to astronomy and the space program.
Orion’s Child is especially pleased to interview Dr. Kondo about Solar Power Satellites and science
fiction made real.

Orion’s Child: How did you move from the realm of science to the realm of science fiction?

Dr. Kondo (hereafter E.K.): Robert Heinlein invited me to his party in Annapolis, where I met Jim
Baen. After the very enjoyable party, Jim took us to a bar in Georgetown, where Jim was staying. Jim
invited me to write for him; I did not give a clear answer at the time. Heinlein phoned me a few days
later. Apparently, Jim had phoned Heinlein to tell him something to the effect that I was writing for him.
Heinlein told me he was happy to hear that I was writing for Jim since we two had met at his party. I
could not very well disappoint Heinlein, so I got in touch with Jim and told him my answer was "Yes".
When Heinlein's agent, Eleanor Wood, forwarded to me the contract, it was for FOUR (!) novels. My
goodness! In any case, Eleanor became my literary agent without signing any contract.

OC: In your book Legacy of Prometheus you wrote about the notion of using geosynchronous solar
satellites to beam energy down to earth via microwaves. Are such power satellites a technological
fiction or do we currently have the technology for them?

E.K.: Some of the technologies are yet to be proven in real life but  the concept of solar power
satellites does not involve any unknown and untested physical principles. Japan had a plan for orbiting
a small scale SPS — generating power in the kilowatts in non-geo-synchronous orbit as a test bed —
but I am not sure where that project stands now.

OC: Why do we need a satellite? Why not build big solar panels on the ground?

E.K.  We should by all means build solar power panels but they would not be suitable in large scale to
harness energy for cities and industries. Ground-based panels have to cope with day-night cycles,
weather, etc. SPS in geosynchronous orbits can provide electricity to its customers day and night,
except a brief eclipse season (by Earth’s shadow) once a year.  Other SPS can provide electricity to
the customers during the eclipse season for one SPS.

OC: How much power could we draw from such a satellite in a realistic scenario?

E.K. An SPS with the effective sunlight collecting area of several square kilometers can generate
about a gigawatt of electricity, which is about what a typical nuclear power station generates.  For
comparison, the Three Gorges Dam, the largest hydroelectric power station in the world, generates,
when fully working, a few tens of gigawatts.  It cost at least some 40-50 billion dollars to build it (in
the Beijin accounting system) without considering the human cost of displacing the villages that had to
be evacuated or relocated.

OC: What sort of infrastructure would be needed on the ground to receive the transmitted power?

E.K. The rectenna, the receiving antenna, would be about ten kilometers by several kilometers in size,
and there would need to be a suitable power transmission system for the power we receive through
the rectenna. In addition to wire transmission of the power, we might consider microwave
transmission from tower-tower.

OC: Would the power transmission be a danger to birds, airplanes, or the ozone layer?

E.K. The power transmission would not present a danger to birds or animals on the ground, or in
flight, although I would not build a house right below the rectenna. You could probably keep cattle
under the rectennae. Power transmission would NOT destroy the ozone layer and would not interfere
with communications.

OC: Won't power satellites be easy to shoot down, and thus be vulnerable from a national security
perspective?

E.K.  SPSs will be sitting ducks for enemy attacks.

OC: Would a geosynchronous solar satellite need to be over the equator? Would that require that the
rectenna be on or near the equator?

E.K. You have to distinguish between 'geosynchronous' and 'geostationary'. A geostationary satellite
must be over the equator.  We don't have a good launch site for geostationary. In terms of launch, the
closer you get to the equator the more efficient it is energy-wise. Brazil has a good launch site along
the Amazon. Unfortunately, most equatorial countries are not politically stable. A geosynchronous
satellite need not be over the equator. It could be practical for an SPS to have a geosynchronous orbit
rather than a geostationary. But in either case, the rectenna wouldn't need to be on the equator.
That's what helps make it cost effective. You can avoid the cost of transmission wires.

OC: How large, on what scale, would the solar power panels need to be to draw a significant amount
of power—are we talking on the scale of houses, city blocks, or asteroid Yojikondo?

E.K. Several square kilometers — i.e., a few kilometers by several kilometers — for generating one
gigawatt.  It would probably make sense to assemble an SPS in orbit, especially when we have
completely reusable rockets for economic access to low Earth orbit.

OC: Won’t something so large be vulnerable to impacts by micrometeorites or space trash?

E.K. Practically all artificial satellites have solar panels to provide power but none, to our knowledge,
stopped functioning from collisions with micrometeorites.

OC: Historically, what role has science fiction had in promoting real science? Do you think science
fiction should predict or promote science or is there room for the just the good ol' story?

E.K. Science fiction stories, even somewhat poorly conceived ones, can inspire the reader to dream.  
Dreams are where many technological and scientific advances come from. Space flights were dreams
only a few generations ago — as was the cell phone in the early Star Trek shows. Of course, unless
the story is fun to read, nobody will read it; so, it has got be entertaining to read.

And, as our interview proves, real science can be and is as fascinating as fiction.  Orion’s Child is
very grateful to Dr. Kondo for his time; and as always we are committed to promoting the dreams
that might one day become the reality.
An OC Exclusive
EDITOR'S NOTE: The following contains many great links, gathered by author Mark McCormick.  
We recommend trying some of them!