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RE: [cdn-nucl-l] Moon could meet Earth's power needs, lawmakers told
Thanks for the quick response and great links Adam.
I would only add a couple of things.
One is that more recently, laser light has also been demonstrated in power
transmission, albeit at relatively low power (see article below).
The other is that high-power microwave power transmission was first
demonstrated in the mid-seventies.
The photo caption in a 1977 book by T.A. Happenheimer states, "Test of the
transmission of energy via a microwave beam. In this experiment at the
Goldstone tracking station [near Barstow, Ca.], the 85-foot antenna in the
foreground transmitted up to 400 kilowatts of power to the receiver panels
mounted on the tower, a mile away. The microwaves were converted to
direct-current electricity with an efficiency of over 82 percent and used to
power the bank of lights below the tower. (Courtesy Jet Propulsion
NASA conducts first flight of laser-powered aircraft
In a possible first step toward eliminating the need for certain aircraft to
carry fuel, NASA engineers have conducted the first flight of a
laser-powered model airplane, the aerospace agency announced Oct. 9.
The flight took place Sept. 18 at NASA's Marshall Space Flight Center in
Huntsville, Ala. The five-foot wingspan airplane flew circles indoors while
a technician manually directed an invisible beam of laser light at an
infrared-sensitive panel of photovoltaic cells attached to it (see picture).
The flight took place indoors to eliminate possible adverse effects from
wind and weather.
Engineers at NASA's Dryden Flight Research Center in Edwards, Calif., built
the 11-ounce, radio-controlled model aircraft, which is constructed of balsa
wood and carbon fiber tubing covered with Mylar film. Participants from the
University of Alabama in Huntsville selected and tested the panel of
photovoltaic cells, which converts the energy from the laser wavelength into
electricity to power the six-watt motor that spins the propeller.
Technicians wearing protective eyewear released the airplane from a
launching platform, at which point the laser beam was aimed at the
airplane's panels, causing the propeller to spin. When the laser was
switched off the plane glided to a landing. Such a plane could keep flying
as long as the power source remained uninterrupted, according to Robert
Burdine, Marshall's laser project manager for the tests.
"This is the first time that we know of that a plane has been powered only
by the energy of laser light," Burdine said in a statement. "It really is a
groundbreaking development for aviation."
The next step for the team will be to analyze flight data and begin
formulating proposals for larger-scale demos, NASA spokesman Jerry Berg told
Remote sensing, telecommunications
The demonstration is a key step toward developing the ability to beam power
to a plane in the air, according to NASA. Without the need for onboard fuel
or batteries, such a plane could carry scientific or communication equipment
for indefinite periods, possibly making it an attractive option for the
remote sensing and telecommunications industries.
"A telecommunications company could put transponders on an airplane and fly
it over a city," David Bushman, project manager for beamed energy at Dryden,
said in a statement. "The aircraft could be used for everything from
relaying cell phone calls to cable television or Internet connections."
The September flights were preceded by a series of demonstration flights
conducted last year at Dryden that used a searchlight as the power source.
An aircraft was flown using microwave energy 20 years ago, according to
NASA, but the flights at the Marshall Center marked the first time beamed
light energy has been used to fly an airplane.
- Jefferson Morris (jeff_morris@AviationNow.com)
[mailto:firstname.lastname@example.org.McMaster.CA]On Behalf Of Adam
Sent: Saturday, November 08, 2003 12:10 PM
To: 'multiple cdn'
Subject: RE: [cdn-nucl-l] Moon could meet Earth's power needs, lawmakers
I believe the idea is to transmit energy in the form of microwaves
(typically mentioned as 2.45 GHz - similar to most cell phones - up to 35
GHz). Achievable efficiency appears to be (currently) ~50%. Check out NASA
for a good intro, at:
Beam it Down, Scotty!
And for more depth:
Solar Power in Space
High Power Converter of Microwaves into DC
Efficient Electrostatic-Accelerator Free Electron Masers for Atmospheric
Hope that helps,
[mailto:email@example.com.McMaster.CA] On Behalf Of Englishes
Sent: Saturday, November 08, 2003 6:23 AM
To: Jaro; multiple cdn
Subject: Re: [cdn-nucl-l] Moon could meet Earth's power needs, lawmakers
A few questions which, no doubt, will display my ignorance; (not that it
takes much to display it).. 1. What is a power beam? 2. How does it work?
3. How much power is lost in transmission?
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