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NASA Abandons SimCIty Microwave Power Concept
TexasDex writes "Wired reports: The NASA Space Solar Power project--a method of collecting solar energy efficiently from space and beaming it down to earth--was canceled in early 2001 after enjoying intermittent attention from scientists. NASA officials cited a policy shift toward the International Space Station and the space shuttle program. But there is still hope for it yet. A conference this month in spain hopes to advance the cause, dispite the fact that there is no public funding available in the US for this project. Some even claim that microwave power is essential for farther explanation. Accordong to the folks at Maxis, Microwave power should be available around 2020, depending on which version of SimCity you play."
Most designs for such a system use a phased-array antenna for transmit - the beam angle can be switched in milliseconds.
They also use a very large beam with a very low power density, so that even if you were to stand in the middle of the beam you would not be cooked - you'd just feel warmth like standing in the sun.
Lastly, most designs use a retroreflector on the ground to send a small reference signal back to the bird, which uses the reference signal to steer the beam. If the beam drifts, the reference signal is lost and the system shuts down automatically.
www.eFax.com are spammers
Hi there,
So many geeks and nobody read "Reason" (Supossedly 2015 AD. I, Robot; The Complete Robot; Robot Visions) ??? In that story eveything happens in a satellite around the sun that collects the energy to beam it down to Earth.
Shame on you guys... but the point is that its an OLD idea.
Read Asimov, its great!
Economic energy intensity numbers mean you're using about 10 MJ for every dollar. Typical ground-side power plants cost on the order of $1000 - $3000/kW (nuclear on the high end of that, coal on the low end) which translates to 10-30 GJ/kW, or 10 - 30 million seconds - i.e. the energy payback is a few months to a year.
For a space power plant to be economically competitive, it's numbers had better be pretty close. Unfortunately right now space launch is about a factor of 10 too expensive, which puts the energy payback into the few to 10-year timeframe.
By the way, I'm the one quoted in the Wired article as saying $10 billion RD&D over 10 years would do the trick - but I don't remember saying it had to go through NASA! And yes, I will be in Spain at the meeting next week.
Energy: time to change the picture.
The earliest I've seen this power source suggested was in Asimov's I, Robot. Unfortunately, I don't have a copy on me to check the dates ;)
Do you see what I did there?