Beamed Space Solar Power Plant To Open In 2016?

Eric_S writes "Anybody who managed to get a decent city going in Sim City 2000 remembers the microwave power plant; now it seems like a real-world equivalent might be coming up on the horizon. The Pacific Gas and Electricity Company, per this 'interview' with the CEO of Solaren on their affiliated site, announced PG&E's plans to buy 200MW of base-load power from a Solaren beamed space solar power plant by 2016." I wish the skeptic in me would be quiet.

Comments

Demand?

[ComputerDruid]

While this kind of power beaming technology is possible, I can't imagine that it's all that efficient. Are we really low enough on other forms of power that there will be enough demand to support this kind of remote endeavor?

Re:Demand?

[john.r.strohm]

On power: The object of the exercise is to put the solar arrays in space, cut out all the atmospheric attenuation due to air and clouds, and then send the power down using microwaves, on wavelengths that are not significantly attenuated by air and clouds.

On pointing: You've never heard of electronically-steered phased array radar, have you?

On efficiency: When the Jet Propulsion Lab tested microwave power beam technology in the 1960s, between two mountains several miles apart, they were hoping to get 63% transmission efficiency. They actually got over 80%. (I think the number was 88%, but don't quote me.)

The key concept on the efficiency question is that solar power in space is effectively unlimited, when compared with available solar power at ground level, because of atmospheric attenuation of light. (Photographers who shoot outdoors know all about this.) Once you have unlimited power at the head end, you don't really care very much about losses due to beamforming.

My source on this is a talk given by Jerry Pournelle in Austin TX in the late 1970s. His slides included photographs of the actual test apparatus, including one of the lit-up light board at the receiving site.

For specific applications, YES! (Remote Military)

[StCredZero]

For specific kinds of applications, yes, there is demand. DARPA is interested in this, because electronics use, and there fore electricity use, by the military has expanded tremendously, even in remote locations. A diesel generator has to receive a constant supply of fuel. This is very expensive and inconvenient on the top of a mountain in Afghanistan. A solar power receiving station doesn't. The power supply is invulnerable to attack. The receiving station doesn't make constant noise. In such contexts, power delivered at rates an order of magnitude higher than commercial generation is very competitive.

We should build something like the Iraqi Super-cannon. The thing was built out of 70's tech and was slated to deliver stuff to orbit for $600/Kg. We could improve on that with new tech and mass production of the rocket-boosted projectiles. Construction materials for SPS could be packaged to survive the G's of being shot out of a cannon. Even electronic components could be built to survive. The US government has specs for electronic components that can survive 100,000 G. (Yes, one hundred thousand!) That would make SPS much cheaper.

Re:Global warming?

[hort_wort]

I asked this question of an Environmental Physicist. The answer is that it will *prevent* global warming. The reasoning is this:

Right now, we primarily burn coal to produce energy. This isn't an efficient process at all, putting out about 30% energy and 70% heat. Also, there are all the waste products dumped into the atmosphere associated with burning coal. Meanwhile, beaming the energy back to the Earth will (theoretically) be very, very efficient, as in almost all the energy beamed back will be reclaimed as electricity. Replacing coal with this method would reduce the overall heat by 70%.

So yes, this idea will heat the Earth, but not nearly as much as coal. As far as causing other weather changes, health problems, and electronic problems, those are possibilities that are unknown until they try it. The signal should be directed quite precisely to their receiver on Earth, and with any intelligence, they will have a safety system such that the beam shuts off immediately if the receiver notices a dip in power.