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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.
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?
There is only one advantage to space based solar power: Essentially no night in space. That is not a good enough reason to shoot that much material into a geostationary orbit. Solar cells age faster in space due to hard radiation. The losses from wireless power transmission further reduce the feasibility. If anyone builds a solar powered microwave beam in space, that is clearly weapons technology, not even dual-use technology.
I'd be concerned with maybe its effects on the weather, maybe global warming. Also, this could affect radio communications on Earth. Or perhaps not, since it probably would operate off of a different frequency. Personally I think that geothermal energy is still a method of energy production that has yet to be tapped on a more massive scale. Why put up satellites and beam power back to Earth when we have excellent sources of power here?
Proudly posting without RTFA.
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.
Satellite in geostable orbit. Receiving station on equator. Receiving station emits guiding signal to satellite, causing satellite to beam power to earth. If the guiding signal is missing, the satellite stops beaming power and starts using that power to adjust it's position. That's how I'd do it.
-1 Uncomfortable Truth
Assuming everything goes well and this becomes a viable source of energy What stops any oil producing nation from blowing it up?
as it is eaten so it shall pass
lots of pissed birds, bats, pollen and insects too.
Some drink at the fountain of knowledge. Others just gargle.
Since the OP didn't reply, I'll have a stab.
"First, a "few times" noon sunlight power, I think would be pretty brutal."
The OP was talking about transiting the collection area, not camping out there. Also we're talking about microwaves rather than visible/UV from sunlight, you will have to ask someone else what the equivalent energy of 3x noon sunlight in microwave form will do, but the point is we're not simply talking about noon sunlight x3, it's not visible/UV at all.
"Doesn't a "few times" noon sunlight power mean that your getting only a "few times" what you'd be getting from the sun by itself..."
Again, we're talking microwaves. Microwaves can be converted to electricity with an efficiency of 75% plus using a rectenna, this is many times the best efficiency we can currently achieve with visible light (typically ~15%). So if you have a beam energy density 3x sunlight, and a conversion efficiency 5x photovoltaics, that give you and output energy 15x what you would get directly converting sunlight using photovoltaics, not just 3x.
Oh no... it's the future.
Actually, isn't the satellite simply intercepting the energy that would have made it to the Earth anyhow?
If this system has about a 50% efficiency, then isn't this satellite actually blocking the other 50% of said energy from actually ever reaching the earth?
Still #1 -- Lonely Gay Geek
So, the gigantic effort to put this solar plant into orbit will create... 200MW of power?
Contrast to this: 0.3% of the Sahara could power the whole of Europe
It's expensive like hell, sure, but it would start delivering energy long before it's completed and its goals are way more ambitious than this flying solar panel's! Think no more unrenewable energy, no more CO2, no more pollutants (sulphur, heavy metals etc.) from coal plants, no more soil erosion due to dams, no more gas or oil (yeah, in italy they have plenty of those) power plants. Only a few windfarms and perhaps the French nuclear plants to iron out the energy needs during night time.
Don't tell me the USA has a lack of sun and deserts.
"The agriculture ministry is not in charge of Gundam" - Japanese ministry official.
This orbiting solar plant would have to be in a geosynchronous orbit to beam the energy to the antenna. It could not beam power 24/7.
I've noticed over my life, that incredible claims of new ways to deal with energy issues are '7 years out'.
BlackLight Power back in 2000 were claiming a 'battery the size of a briefcase that can power an electric car 1000 miles' as an example.
Now, here we have this new claim.
Yet these people point out that the energy here on earth from one of the downlinks is only 2X that of regular old PV.
URSI White Paper on Solar Power Satellite (SPS) Systems
So whom to believe? A guy seeking venture capital OR a bunch of wet blanket boffins?
The reason is that currently, the western militia there must import lots of fuel to provide electricity. That is EXPENSIVE. VERY EXPENSIVE. Instead, the groups could put up one of these that have say 5-50 MW and then put small collectors on the ground. It would be MUCH cheaper than bringing in the equipment and fuel. In addition, if a base is overrun, it would be easy to prevent enemy (read Al Qaeda) from using the equipment and new equipment would be much lighter, easier to take care of, etc. Also, once several of these were up there, they could be shifted around to help on Emergency locations. For example, helping Hurricanes, tsunami, Chinese EarthQuake, 9/11, etc. The ability to get power into a large disaster area means, LITERALLY life or death. If we put at least one over every major continent, they could be used normally to help a city that already has coal/gas, but then moved ahead of time for when a disaster is heading there way (hurricanes), or a day or two for unseen disasters that happen. Heck, if done right, private space industry should push this private tugs. These can then be used for doing other work (perhaps getting rid of space junk).
I prefer the "u" in honour as it seems to be missing these days.
Except that in space, you don't need to deal with atmospheric attenuation. That increases the effective power output of your solar cells quite a bit, even if their efficiency is the same. 50% (to pick an arbitrary figure) of 500MW is a lot more than 50% of 250MW.
[citation needed]
See, I think that your comment is FUD. I think that if these microwaves are at the right frequency to excite water molecules (and thus hurt animals) that they'd also be absorbed by the atmosphere and thus not useful for the transmission of power. But every time this story comes up, someone makes a post based on fear. How sad.
They must have some big economies somewhere they aren't talking about to make this profitable.
Seastead this.
If wifi,bluetooth and am/fm waves are so similar, there must be plenty of energy floating around us. Why can't we just recover that energy? Power your laptop from your WiFi signal. Heck, with all the radio stations transmitting around us we should be able to pluck a few dozen frequencies and power the radio itself.
How efficient are these antennas again?
The stray microwave radiation is of a much lower average power. In addition, it is spread across a much larger spectrum, making it difficult to grab all the energy at once.
This plant will send a higher power, focused beam of a single frequency, making it highly efficient. Nokia is working on a system like you describe, though it only gets about 10mW of power currently.
Write your representatives! Repeal the 2nd Law of Thermodynamics!
Still the economics of this are a bit puzzling. In 2008, California used 285 million megawatt-hours of electricity, so even if this project could generate 200 MW 24x7 that still comes to just 511,000 megawatt-hours per year, or a little under 0.2% of Californian consumption. At a wholesale price of $50 per megawatt-hour, that would earn Solaren about $25 million per year. Even over the fifteen year projected lifespan that comes to just $375 million (actually less if you take inflation into account). Is $375 million anywhere near what the actual cost of this project will be? Space engineers, please help here.
A phased-array antenna at 2.45 GHz still has a rather wide beam. I would say that a parabolic reflector has a narrower beam than a phased-array antenna - especially at 2.45 GHz. If this were operating at a higher frequency, then sure, you can get a pretty tight beam, but then you start having other atmospheric absorption problems. Rain would be terrible at just about any higher frequency, not to mention oxygen and nitrogen also start absorbing the higher in frequency you go.
Plus - a really tight beam has many negative problems - if you keep a really high power density - the lower air pressure in upper parts of the atmosphere are likely to form plasma. The electric-field strength due to the high power density can cause that flash over to occur, and once that plasma forms - oh shit - all sorts of weird things can happen. The plasma can start reflecting RF energy, it can just keep absorbing it, and it may even let some through - but it's more likely to reflect or absorb once the plasma is formed.
Any way - back to the phased array thing - the main benefit of phased-array transmitters is the ability to steer the beam with no moving parts.
Works great for radar systems - less so - in my opinion for microwave power transfer.
This company really just needs to launch a test satellite first, but you would want to test it at a very high power density, because that's what's needed, as that's when all the weird effects start to happen. Lots of ground experiments would need to be performed, but even then - the whole thing could get launched, and some unforeseen consequence happens, and we've just wasted billions upon billions of dollars.