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Solar Power Satellites by 2020?
soulfuct writes: "Finally, a national space agency has budgeted funds for a test project to convert solar energy in space to microwaves and beam them down to Earth. They plan to deploy this for use by 2020. Kudos go to the National Space Development Agency of Japan (NASDA) and Kyoto University for being the first to realistically act on the idea of solar power satellites promoted decades ago by Gerard K O'Neill in his book The High Frontier. With all of Bush's rhetoric about an energy crisis, why doesn't NASA latch onto this idea to secure more funding?"
Just what *did* you think that cloudy sky that shows up on the startup screen was supposed to mean?
hawk
The real reason for Bush's "energy crisis" rhetoric is to funnel more money into the pockets of his friends in the oil business and to justify further destruction of the environment.
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Speaking of nuking cows with megawatts of microwaves, compare that with all the talk about 0.6 watts of cellphone radiation causing brain cancer.
The aircraft thing isn't actually a big deal.
... but not very many! Any violation would probably be by private pilots.
...)
... in order to have a commercial flight wander into a beam you would probably have to have both a ground controller and the pilot mess up. And all of the computers involved on both sides get messed up too (or ignored). Not very likely.
... this is nothing new. Controlled access airspace has been around a long time.
... they are on their own ...
...
....
Go out and find (I would bet you could get some example off the net) an aviation sectional chart. You would be amazed at all of the areas marked off as restricted or off limit airspace. (Controlled airspace of all types, military training areas, missile ranges, etc.) Yes there are violations of these areas, and yes there probably would be some violations of uwave transmission beams
(Private pilots in general are pretty good at following the rules. In my exerience anyway. Mostly because the rules tend to make sense. However after spending some time with a few in Yuba county CA, I no longer believe that all of them even try to follow the rules. Or even get a license. Glad I don't live out there
Any incident with a IFR (read as: commercial traffic) aircraft running into a beam would be even more unlikely. Commercial pilots (the ones I've met anyway) are unbelievably paranoid about running into things. These are people who think of inter-aircraft clearance distances in terms of miles! They are very aware of where they are and where they are going. Soooo
The other worry you expressed about uwave interferance is not an issue. We would be talking about a direct beam here. The scatter would probably be quite small, and the restricted airspace around the beam would most likely be large enough to avoid that problem entirely.
So in conclusion to the aircraft issue
As far as birds go
I have a feeling that powersats would hurt far fewer birds than wind generators though.
I think it could be fun trying to design orbits to avoid running any other sattelite with a lower orbit through the beam though
In any case it would be good to work all of this stuff out now, with solar power. This paves the way for moving nuke plants (and hopefully fusion plants someday) off the surface and into orbit.
wow, this is getting quite long
OUT
"There's no secret. You just press the accelerator to the floor and keep turning left." -- Bill Vukovich
This has been talked about for many years. The trick is to do it safely. High-power microwave being beamed down to anywhere other than the intended receiver can be a serious danger. Imagine if that beam lands on, say, a person.
The most obvious solution, and probably the one that will get implemented in one form or another, is for the receiver to transmit a homing signal for the bird to locate, and the power relay only gets turned on when the homing signal is locked in.
One might wonder, though, what kind of danger could exist if some not-so-nice cracker got into the control system of such a satellite and aimed the beam at someone they'd like to cook...
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All people who declare war on humanity (as I did that night) are great. We all have good intentions. But we're always wrong. There is no way to win the war on humanity.
MOD THIS UP!!!! I wish all the neo-anarchists protesting humanity finally linking up around the world would understand this.
the energy crisis is a myth, except in California, where the crisis was created not by a lack of resources but by a botched deregulation
The "Energy Crisis" in California is simple: there is more demand than supply. It has little to do with deregulation.
Had there not been deregulation, I bet there still would not have been new power plants built (enviromental BANAism) and artificial electricity price caps in place, just like the current situation.
Californians are (finally) going to have to pay the price for not building new powerplants. Of course, had true deregulation brought the actual cost of California energy to the ratepayers 10 years ago, I bet there would have been more public support (and more demand from power companies) for building new power plants.
As they often say on Usenet, TANSTAAFL.
However, California is only one state that disconnected the link between demand and supply. Expect that in other states whose regulatory bodies have tried to unliaterally "turn off economics" that there will be similar problems.
But then again, so are oil, coal, and nuclear power
People forget about the dangers of our existing fossil fuel based electrictal generation system in the US.
Coal fired plants release more radioactivity into the atmosphere than nuclear plants. Coal-fired plants operate at far higher temperatures and pressures than nuclear, and the risk of explosion is far greater. There have been more deaths in the United States with coal-fired plant accidents than with nuclear-plant accidents. Coal-fired plants require a significant transportation system (railway, barge/dock) to feed the plant. A nuclear plant can be fed for 18 months with a single delivery by a flatbed truck.
What about frying birds and such? Any environmentalists wanna comment? :)
The smaller oil companies, the ones run by people like GWB, are the ones likely to be squashed if alternative fuels take off, and that is why they are buying . . . er, donating heavily do . . . politicians at the moment.
Go you big red fire engine!
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
Apparently, though, the risks have been pretty carefully considered and the conclusion is that this isn't much of a problem compared to suntanning or eating a typical American diet. As pointed out elsewhere, this frequency is non-ionizing and therefore does not cause chemical reactions. It can heat you up in significant intensities but nothing more, and the intensities under consideration would cause only about as much heating as being outside on a hot day.
From the website cited above: What if the beam wanders off from the rectenna? The beam can't wander off target with a significant intensity because it needs constant feedback from the rectenna for focusing. (A phased-array system is necessary for successful focusing onto the rectenna at such distances.) If it wanders off, then it immediately defocusses and disperses to a tiny fraction of its operating intensity. It also can't be used as a weapon for this reason. Even if it were re-engineered to point anywhere with the same focussing, the transmitters would be designed to operate at a relatively benign frequency (e.g., 2.45 GHz) which would not pose a credible threat to anyone. Again, the only thing that will significantly absorb the 2.45 GHz frequency beam is a receiving antenna designed for it.
WWJD for a Klondike Bar?
Surely the oil companies and their presidential puppet will not stand for this blasphemy.
I know I'm going to get marked as a troll or flamebait for this, but here it comes anyway: Clinton had two terms in office, and Mr. "I Invented The Internet" Gore did what for the California energy crisis? The power problems in California didn't suddenly begin in January when Bush took office - they've been brewing for years. Never heard of Gore doing anything about it, did you? Hmm, don't hear Gore speaking up too much about that energy crisis, do you? Wonder why that is? I don't.
What's your damage, Heather?
Absolutely true, and it accounts for 3/4 of the two-fold difference in the energy it takes to make a dollar of GDP between Europe and the US.
The remaining quarter of the difference is in energy efficiency. Closing the energy efficiency gap would conclusively solve the energy "crisis", much more so than the small increment of production Bush is proposing.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
there is a benifit to doing it in space. they dont have clouds in space. the power production would be constant. this is something that isnt always achieveable on earth.
use LaTeX? want an online reference manager that
-- john
Sorry, this idea has already been patented by first right by the developers of Sim City 2000. (tm)
©o,,o©©o,,o©©©o,
I never thought that AOL CDs were a worldwide early-warning system against Microwave attacks from nasty dictatorships.
...thinks that renewable alternative sources of energy are not "practical" enough to seriously research and fund, but a fancifal multibillion dollar ballistic missile shield is...
ok, that's my political troll for the day...just thought it was ironic
It's 10 PM. Do you know if you're un-American?
With all of Bush's rhetoric about an energy crisis, why doesn't NASA latch onto this idea to secure more funding?
I don't know, cause it's fantasia bullshit?
How we know is more important than what we know.
I just hope they calculated with the energy spent on bringing those solar panels in position. A rocket uses huge amounts of energy to enter orbit. :)
And what about maintaining.. they gonna send electritions up to the moon when things break... sounds rather costly
The first is a good point.
Actually, making the solar panels on the Moon isn't that bad an idea. Or at least grabbing more of the resources from there, a lot less costly (in energy) to move mass from the Lunar surface to geosysnc earth orbit than from the Earth's gravity well.
Same for electricians, really, given a lunar base/factory.
Mr. "I Invented The Internet" Gore
You know, every time someone trots out that tired phrase, they instantly lose credibility.
I'm not going to go into the reasons why his "claim" wasn't a claim at all, and even if it was, the people who *did* invent the Internet backed him. It's not worth the old arguments.
-Todd
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"The details of my life are quite inconsequential..."
Slow down cowboy. The rhetoric is coming from the media, not the President. The media-mantra for the past three months has been that the energy crisis will bring down the presidency. Meanwhile gas prices are still cheaper than in 1999 under Clinton and considerably cheaper than in 1978 under Carter. As for the power crisis in California and the potential for a future shortage nationwide, I dont see any rehtoric at all. Clearly there is a short term crisis in California, and a long term problem for the rest of the country. While I am all for science R&D, statements like yours are rediculous. Commercial orbiting solar power stations are many years from becoming a reality along with fusion and mid-ocean tidal power plants. These technologies are exciting and certainly deserve funding and our interests. However, penciling in preposterous "unproven tech" in a national policy has already gotten Bush in trouble with Missile Defense. Do you suggest that he do the same will all of his policies?
There is no world conspiracy to drive up gas prices in the United States other than OPEC. Outside of the OPEC nations, the U.S. consumers enjoy the cheapest gas prices in the world. The energy crisis is one of refineries and a lack power plants.
Conservation is important, but what is more efficient, spending resources to become more efficient or spending resources to generate more power. Look at software engineering. Is /. authored with a custom C-solution. It would be alot faster than perl and appache. Why bother with an OS. Why not write an embedded system, it would be more efficient. Why use a generic relational database and not write something spesifically for your needs. Efficiency does not always translate into better (look at Java, Perl, Python, etc).
Someone you trust is one of us.
So far as I can see, O'Neill's approach -- that of using nonterrestrial materials -- is the only way solar power satellites will ever prove economical -- with the possible exception of some proposals for urban illumination from earth-oribing mirrors. Sadly, I've seen very little in the way of studies of how to make non-terrestrial resource utilization work coming from mainstream corporate (or governmental) sources.
Since the early 1980s, when it became apparent that NASA's predictions for Shuttle economy were enormously optimistic, there has been a lot of thought put into how to create human-guided self-replicating raw-material processing facilities on the lunar surface and in space as a way of bootstrapping a huge industrial manufacturing infrastructure in those locations. This at the same time as technology has advanced in the relevant areas, thus bringing the cost of such a self-replicating "seed" facility, put in place in space or on the lunar surface, much closer to the level that might make private investors interested.
Ergo, what is needed is a "technology development initiative" by the government, but a release from taxation, those businesses that are pursuing relevant milestones toward the establishment of these capabilities.
Seastead this.
Wow we can now cook birds in flight. I wonder what the effects of microwave radiation are on life? Does it disperse on particles in the atmosphere? Will it heat particles/clouds in the atmosphere? Does mild exposure mutagenic? Hmm, I'm totally skeptical of this technology. Perhaps we could use it in space to move around energy, but I don't know about space to earth..
-Moondog
You can see a breakdown of the new budget for renewable energy here. Funding for solar has been cut 49%, as has wind power.
At the same time, Bush plans to build 1,300 new power stations whilst opening the Alaska wildlife reserve for oil exploration.
Does anyone else feel Bush was voted in the wrong decade?
Phillip.
Property for sale in Nice, France
Actually, the reason why such a large antenna array is needed on the ground is due to the diffusion of the beam. By the time it gets to the surface, it is *mostly harmless* or so it has been said over the years by its proponents. O'Neill and others proposed the construction of a large mesh array antenna that would pass sunlight and could be situated over cattle grazing land. Feasibility studies have been done in the past, and the only real problem was the construction cost in space.
The atomspheric energy absorption is not high enough to make this inefficient and does not really contribute to making this *mostly harmless*. The reason it becomes *mostly harmless* is due to dispersion of the beam over a large area. So, a larger antenna is used to pick it up.
People need to check out the solar power satellites link cited in the post. The safety details have been addressed long ago.
Oh, you mean that one the two wealthy oilmen have been talking about? Please.
Even in circumstances where it is "aiming" properly, wouldn't this be a problem for bird and airplanes? If I can't even use my cellphone for fear of interferance in the plane, what about giant beams of microwave radiation??
No solar panels increase albedo, big time. Hardly any of the solar energy that hits them is converted to electricity. Instead it's all converted to heat, solar panels are black after all. Plain sand has a very low albedo being very light color.
Didn't you read the artical and see what it said on how large-scale use of solar would cause a large increase in the absorbtion of sunlight?
Well, the world isn't the United States. For one thing, the U.S. is home to the world's largest oil companies, which aren't all that interested in anything not coming out of the ground. Another, LAND. Solar farms don't work in Japan, which is, to put it gently, overpopulated. Countries like Japan or England or Germany can't unroll miles of mylar on the ground. Solarsats take all the infrastructure and move it into space, where's there's room.
They are also permanent. Besides the beaming equipment, which I assume burns out after time, the solar cells last for a long, long, time.
And a solarsat isn't fragile -- there is no wind, no rain, no earthquakes, no gekkos. It just works, year after year.
As for cheap, after the initial construction, whatevcer it costs, the sat just keeps paying for itself, without stopping. The well doesn't run dry, there are no spills. And we don't have to pave over the deserts, either.
Not that your idea isn't good! It is pretty cheap to panel desert areas.
No geckos, but how about space debris?
There are great many pieces of small debris floating around in orbit after few decades of space program.That's why you have armor plating all over the place in ISS for example. 2mm piece of white paint can be a bitch if the Delta-V is several km/s.
So, yes, there will be wear and tear.
just hack into one of these.
pick a logo for this thing :
"They plump when you cook 'em"
-or-
"Just like ants under a magnifying glass"
Treatment, not tyranny. End the drug war and free our American POWs.
See my user info for links.
I would think that the answer to this is obvious: it doesn't involve improving the lot of existing mineral extraction industries. Remember that Dubya is the guy who proposed cutting funding for alternative energy research by 30% as part of his overall energy program. After all, he doesn't want to risk hurting his friends in the oil industry. Something that could actually replace fossil fuels is exactly what Dubya doesnt' want.
There's no point in questioning authority if you aren't going to listen to the answers.
"Hey, did you hear? They're going to send a spacecraft to the Sun!"
"Wow... isn't that dangerous? The Sun is so hot!"
"Well yeah, normally. But they're going at night."
"Mind, as manifested by the capacity to make choices, is to some extent present in every electron." -Freeman Dyson
Please correct me if I'm wrong, but the only geosynchronous orbits are above the equator. The further a satellite's orbit moves from the equator the wave pattern we typically see representing its traversal across the earths surface grows in amplitude.
If the reception site must be directly below the satelite, that means it will not be in the United States. I would suspect George W. Bush is loathe to put US funded energy sources outside US borders...(considering how critical energy is to the sustained growth of the US economy...)
However, I don't see why the beam would have to be perpendicular to the ground. If they do not have to be, a satellite in geosynchronous orbit could beam the energy to a facilities 30 degrees north of their position, which would put them within the continental US.
What a load of old rubbish
List of large man made objects in space:
- International space station
- Ummm
List of large man made objects on earth:
- Empire state building
- Super-tankers
- Pyramids
- etc etc etc
It's not difficult to find large areas of land for collecting solar energy. What do you imagine is in the sahara desert? Well, basically there is a great heap of nothing and lots of sunlight. Yes, there's no people, but running electricty through some cables to europe would still be heaps cheaper than this stupid space idea. And you need lots of room for the receiving antenna anyway.
Three that come to mind:
- Giant circular greenhouse with a huge tower in the middle. Air in the greenhouse gets hot and rushes up the tower which contains a turbine. Cool air enters round the edge. This works and there is a great big prototype somewhere in spain (anyone got any links?). You can grow crops in the green house except for the bit right in the middle where it gets a bit drafty.
- Mirrors like hugs bits if guttering which focus sunlight onto metal pipes with oil in. Oil gets very very hot, boils water, turbine etc. I believe that there are a number of plants like this working in the USA.
- Windmill. Sunlight heats ground, air rises, cold air rushes in and turns blades on great big fan up a tower. Quite a popular solution in many parts of the world.
I predict that all of these solutions will be substantially cheaper than this stupid space power idea until long after all of us are dead.
As others have pointed out, it's still a navigation hazard. And you do have to worry about birds falling out of the sky and all.
I remember reading about this idea in futurist books as a kid, and by the time I stopped being interested in this sort of literature (just don't pick much of it up anymore) the idea was already being dismissed. Okay, it diffuses. But that's not much help.
Over-the-air power transmission on any scale larger than what's needed to power a bug (I believe the Russians did this) is too much of a risk. It's an interesting idea that I think someone floated without really giving a lot of thought to it. You could probably do a ground-based version with a massive solar array and a waveguide to pipe the energy where it needs to go, but that would sort of miss the point of the technology, wouldn't it? Putting it out in the middle of nowhere isn't really going the help when you still run the risk of frying anything that flies through the beam (last I checked I didn't think it was common practice for airplanes to reroute around deserts...)
/Brian
My question is not "can it be done?" but (environmentally speaking) " should it be done?" Think of all the mile of nature destroyed on our already over-crowding planet. Some of the solution, of course, may involve population (which may "solve" itself with disease), but in mean time, perhap better plan would be more efficiency / less waste. It may be that this (alone) is not the best way -- but if it were efficient it might be help. And using on the massive wasteland of city and suburban roof tops might just be a good idea.
Of course, I suppose ecconomics could get in the way (damn if I don't hate captitalism and suspect its the best we can hope for at the same time).... :(
Comment removed based on user account deletion
And what about maintaining.. they gonna send electritions up to the moon when things break... sounds rather costly :)
Probable impossibilities are to be preferred to improbable possibilities.
Aristotele
Don't give it to NASA, that's the place you send stuff you want to kill off.
We could put put bunches of this stuff along the desert near the US Mexican Border. Not only will we get power, but since the facilites each cover a mile or two, they will act as a natural wall stopping illegal immigration
Yes I know it's sick.
Quit it already with the baseball bats
Check out the Vinny the Vampire comic strip
"It is a greater offense to steal men's labor, than their clothes"
if you can transmit enough energy to power a city, you can also transmit enough power to destroy a city. there is also the question of leakage. even if you use a maser format to transmit the energy, there will be a certain amount of bleed over. a standard satellite broadcasts 5 watts of signal, a dss about 35 watts. a solar satellite broadcasting a few megawatts may very well blank out all other satellite communication.
This has been one of those Real Soon Now (tm) projects for years, for a simple reason - assuming your solar cells are made of silicon or something of similar density, the mass of an SPS (solar power satellite) big enough to generate useful amounts of power is prohibitive.
Here's my calculations:
Assuming a solar cell 1m to a side and 1mm thick, we get: 0.001m^3/cell * 2330 kg/m^3 (the density of silicon from Webelements ) = 2.33 kg per cell.
The solar irradiance at Earth's orbit is 1367.6 W/m^2 (from NASA National Space Science Data Center ). We currently have solar cells that can convert solar energy to electrical energy at about 30% efficiency in the labs. So, we'll assume that these can be made in bulk sometime in the near future. That yields 1367.6 * 0.3 = 410.28 W/m^2.
That seems like a lot, but consider - it four 100 watt light bulbs, or your computer (no monitor), if you have a system like mine. Lets say we aim for a generating capacity nearer to your average nuclear plant - 2 megawatts. Then we need 2,000,000 / 410.28 = 4,875 panels. At 2.33 kg each that's 11.4 metric tonnes. Not a huge amount, but then you have to add about that much in support structures, repair equipment, and the microwave emmitter, of course.
You will note that I have ignored losses in transmission, etc after the power is converted from solar to electrical. That is because these conversions are all very efficient, compared to the solar/electrical conversion, so they don't change any mass calculations by that much.
So how many SPS units would we need to power the world? From the CIA World FactBook , the US in 1998 used 3.365 trillion kWh, equivalent to a continous 384 million kW. We would therefore need about 200 thousand of the 2 megawatt stations considered above, for the US alone. If we wanted to be generous and extend this technology to the rest of the globe, we need over 2 million stations of this size.
Now, this is clearly not economical, not with launch costs in the neighborhood of $500/kg for the Shuttle (some dumb boosters can haul more for only $100/kg), but there is still hope. John S. Lewis, in his book Mining The Sky shows that building SPS units is economical, if you don't have to launch the mass of the solar cells. Instead, you bootstrap - launch a processing facility to a target Near Earth Object, set down and start making solar cells. The facility would have to be unmanned, but it would in a few years time produce enough cells to build a SPS.
One thing's for sure: You sure won't see any of this from NASA. They'd like it if you gave them the trillions of dollars it would take to build one of these, so they could fail miserably and call the whole idea impossible.
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Vpered na Mars!
It couldn't be because NASA still doesn't have a new Administrator, could it?
Seriously, the fact that we're 100+ days into the Bush Administration [which I helped vote into office] yet do not have a NASA Administrator--despite having plenty of excellent candidates inside and outside of NASA--is a travesty. It's high time for Bush and his staff to make their pick and get rid of Dan Goldin, who's set NASA back at least ten years.
-- Geof F. Morris
I will use my orbiting solar power stations of death to destroy the world's cities, unless you pay me 10... Million dollars!
C'mon, throw me a fricking bone here...
Just because you can mod me down, doesn't mean you're right. Shoes for industry!
Not that greenhouse gases & whatnot aren't speeding global warming along enough on their own - we'll just lend them a helping hand by superheating a few more cubic miles of atmosphere.
Sheesh!
Blue skies... Barthie burgers... girls.
there's no light in space dammit...you remember all the space pictures from nasa...no light
that was meant to be a joke...forgot to write: ...joke
I doubt that targeting would be the problem, unless the collection site was in a geologically unstable site. Suppose for a moment, that equipment was setup in California, to recieve microwaves and convert them to usable electricity. Suppose now that there was seismic activity which cause the reception equipment to go out of alignment with the space based delivery mechanism. Not only would the area have been ravaged by an earthquake, but also the power generation capability of the region would be disabled. Not only would I not be able to get power to my house because the lines were severed, but there would simply be no power to be had. This will make for difficult selection of reception sites for this system. It must be in a geologically stable region, with consistant weather conditions (for predictable gain) and there are probably a number ofother similar considerations.
--CTH
--
--Got Lists? | Top 95 Star Wars Line
I think you're right about the transmit and receive angles.. that throws a wrench into my theory. :)
But about my "all men are great before declaring war on humanity," it's actually something that I uttered on IRC while I was talking to my brother. I kind of snapped one night while reading something (I can't remember exactly what it was, but it was something about a person who was imprisoned for something that I don't consider to be wrong). I'm one of those liberal anarchist apologists. :)
Anyway I always considered myself to be a good person.. but every time I read something about a grevious misjustice (guy thrown in jail for 5 years for smoking weed.. 15 year old thrown in jail for "abusing" 16 year old girlfriend (because consent is not possible when you're only 16. Ahem.) or intellectuals threatened or jailed for speaking their mind) I would feel this hate for the perpetrators (read: conservative/religious folks in a position of power). Anyway this one night I was talking casually (on IRC) to my bro about this article I was reading, and it eventually degenerated into a heated argument (only for the sake of argument; he agreed completely) and I started to imagine myself killing the judge.. the police officers.. and anyone involved with removing this person from society. I was totally convinced that I was right, and that the only way to stop the world from destroying itself was to kill all the people who aggressively hunt people they disagree with (whether or not the "criminals" were hurting anyone). This article really fucked me up at the time.
I was in this sort of quiet rage for about half an hour.. when suddenly I realized.. what the hell makes me so damned special? What differentiates me from the people I'm fantasizing about killing (while yelling fuck you agressor - you incarcerate innocent people, you die). It was like.. bam.. everything that I believed I was.. was.. not right.
I kinda dropped a level of conciousness at this point. I think this is what happens before people go insane. :) I don't remember what happened, but apparently I starting saying weird shit for like 15 minutes (that quotation is one of the things I said). When I came to, I was crying. Wierd night, to say the least. :)
I thought.. so this is how it happens.. If you're strong, when you go insane like this, you throw yourself out the window. If you're weak, you grab a shotgun and maul 100 innocent bystandards. If you're lucky like me, you realize that it's time to relax. The world is a fucked up place, and the best you can hope to do is talk.. tolerate.. and try to understand.
All people who declare war on humanity (as I did that night) are great. We all have good intentions. But we're always wrong. There is no way to win the war on humanity. Anyway. That's the story behind my quotation.
--
All men are great
before declaring war
A government is a body of people notably ungoverned - AC
There is no possibility a city will get fried by microwave energy. First of all, any system beaming energy from orbit would use a laser based targetting system. There would be an electrical cutoff if the laser failed to reach the satellite along the return path (which would presumably not be software controllable). So, if the microwave emitter lost the laser "signal" from earth (which would presumably only be receivable on a perpendicular to the ground) by drifting off course or because of a mechanical failure, the microwave emitter would shut down.
Second of all - the microwave beam would not be wide enough to cause mass destruction anyway. The waves would be directed so that it bathes a small target on the ground (less than 10 feet in diameter). So even if the guidance cutoff failed and the satellite were to hit a city with microwaves, the damage would be fairly localized (imagine a disaster the scale of a 747 crashing into a neighborhood - not a nuclear or biological weapon event).
All in all I think this will be an interesting project. Best of luck to them.
--
All men are great
before declaring war
A government is a body of people notably ungoverned - AC
Excuse me, I don't much like political flame-wars on Slashdot. But what you just said is wildly untrue. Dick Cheney still has multi-millions of dollars of options in Halliburton oil, many of which don't vest for several years.
There was a flap about this, and he made some noise about getting rid of them, but then it blew over and he quietly went ahead owning them. So please do some basic research before posting.
As far as the energy crisis... I'm not sure I see any solutions in the Bush plan except drilling the ANWR (a relatively small amount of oil, 10 years out), reducing emissions standards (which simply exacerbates the Not-In-My-Backyard phenomenon which is responsible for a lot of the power companies' troubles, not wild eyed environmentalists or democrats) and of course, Eminant Domain (which pisses off a lot of Bush's key supporters and is rife with legal difficulty.)
I should elaborate that drilling for oil in the ANWR does not mean that America will have more oil, as oil is sold on a global market. It simply means that a few American companies will make more money than they do now. OPEC will still be able to maintain the price, even if the most optimistic estimates of production are met. Simply raising efficiency standards on new cars would save an amount of oil that easily eclipses what's going to come out of ANWR. Now, if we could realistically find a lot more oil, maybe it'd be a real plan, but it's just silliness as it stands.
If this is the case, Bush's plan does nothing-- drilling the ANWR will not increase refinery capacity. Supply is low because a major oil cartel has been deliberately reducing it over the past few years. OPEC could easily have pump prices under a buck if they wanted such a thing. Pumping oil out of the ANWR isn't going to give us any more oil (oil's sold on a global market), and OPEC will reduce supply again to keep the price where they want it. That's not a bad thing for the oil companies that bankrolled the Bush/Cheney campaign, though (nor is it bad for Cheney and his millions in un-vested Halliburton options.)
Furthermore, I'm not sure exactly which crisis you're even talking about? The one in California that was caused by ill-advised insta-deregulation in the 1980s? Or the one at the pump, which (as I just said) has to do with us relying so desperately on a resource controlled by people who (gasp!) don't have our best interests at heart. We could, of course, simply require autos to run more efficiently; the savings in gas would pay for the increased price over and over again, and the oil saved would more than eclipse anything that we're going to get from ANWR.
In any case, most electricity is made from coal, not oil. And the major problem with that is that people don't want coal plants (especially the dirtier coal plants allowed by the Bush plan) anywhere near them (these are regular people, not liberal environmentalists.) We've pretty much choked Native American Reservations with particularly nasty coal plants. Bush's plan aims to solve this by taking land away from people (not popular among the very strong land-rights lobby that generally would support him.) It makes no provisions to even think about wind power, which could easily be providing a significant portion of our power in 10 years (the time it will take for ANWR exploration to begin producing results.) Modern wind technology is rapidly becoming competitive, with enormous multi-megawatt generators bringing down the production price (actually, this stuff is very cool, you should check it out no matter how much you disagree with me on the rest of it.)
And finally, it absolutely rejects the possibility that there might be something to this whole greenhouse effect thing. I might understand questioning the existence of global warming, but to plow ahead with the most vigorous pro-fossile fuel plan since the 70s at a time like this is a waste of taxpayer resources and just plain stupid.
For all of Bush's rhetoric, his budget has already slashed funding for alternative energy research. I think this particular idea would fall under the same axe. I'm not going to draw the obvious conclusion as to what his priorities really are.
Now, if we could bill these solar satellites as some sort of missile-defense...
i would be more impressed by a cheaper easier to install set of efficient solar panels
think about how much energy would be saved if every house and business in cali had solar panels on their roofs
would their still be rolling blackouts ?
besides i'd like to see my own power bill drop below car payment level
But then again, so are oil, coal, and nuclear power. Everytime there's a new tech advance posted here on Slashdot, 50 people reply to the story pointing out how deadly the new tech is. Imagine the replies to the post about Ford releasing the Model T: "So we're just going to let anyone that has $500 drive around some thousand pound chunk of metal powered by EXPLODING GASOLINE! No thanks, I'm sticking to horses!" All technology is dangerous. If you discount a new idea because it's possible to accidentally kill people with it, well, enjoy your cave.
Today is a good day to die. They all are, though.
Like I said, it would take an amount of area similar to current paved roads. That's not a drastic impact on the enviromnent; nobody's claiming that today's pavement is causing Antarctica to melt.
As to finding more petroleum, that's probably not a big deal. We'll run out before doubling the current impact, and we'd need alot of it to make plastic tarp collectors anyway. The real disaster will be if we stupidly manage to burn all the coal that we could potentially scratch out of the ground. That's orders of magnitude more CO2. Have you checked the weather on Venus lately?
It wouldn't have to be especially efficient, just cheap. Unroll acres of the stuff directly onto the desert floor, or float it on the ocean. Maybe put it in the diamond-shape gaps between those circular irrigated crop fields out west.
My math estimates a few thousand square miles of 5% efficient (at 1% overall system efficiency) collectors would satisfy all our energy needs. (If you think that's too much area, imagine explaining how much area would be paved over in 2001 to a guy from the 19th century. It can be done.)
If this was treated like the Manhatten project, I'd bet they could get production started in 7 years or so. By contrast, in 7 years, NASA would still only be doing feasiblity studies on a space-based solution.
Right now, it makes more sense to deploy solar cells on the ground. Or to build nuclear power plants, or wind generators, or electric themocouples. The economics of solar panels don't add up at current launch costs.
At some price point, launching becomes cheap enough that they do. What, exactly, that point is is debatable. It's probably more than one factor of ten below present costs and less than two; it's unquestionably less than three. We should be able to do one factor of ten for large launches by 2020- actually, we could do it by 2005 if there were sufficient demand. So if Japan is planning using this stuff for 2020, they are probably not drastically off-base, and they should certainly start small-scale experiments now.
Incidentally, Japan has somewhat greater energy problems than most places do. They have an extremely high industrial/urban population density; they lack internal energy resources (coal, oil, gas, uranium); they are more nervous than most about nuclear power, for both historical and geographical reasons (it'd be hard to put many power plants in enough isolation from major cities to feel very safe; also, the prevalence of earthquakes and tsunamis would make me rather nervous as a plant designer); and they don't have many wide open spaces to devote to solar cells on the ground. Also, a single generating point for electricity would do much more for the relatively compact nation than it would in the US, where transmission over long distances is a problem, and where we'd still use lots of gasoline anyhow. So it's not surprising that they're pioneering this.
Do you honestly think that capitalism runs an absolutely perfect market in all respects? Solar and wind power require substantial investments of initial capital with an eye towards long-term return- here I mean on the scale of several decades. They face substantial risks, due to the existence of a competing industry that has substantial power in the federal government and massive amounts of capital.
This is where governments typically step in. Government support has been present at the founding of every significant American industry since America industrialized. They subsidized the hell out of the railroads with land grants and more. They subsidized steel. They subsidized oil most of all, letting oil interests massively affect foreign policy, and building a national highway system, not to mention things like inventing and subsidizing jets, which are a whole other oil market. This is what happens. It's perfectly logical. And every single time, previous industries that had built themselves off of subsidies, turned around and cried 'foul' when they feared being replaced by something superior.
And, of course, if we charged fair prices, solar power wouldn't need a subsidy after all- because in fact, every use of oil power is taking a free subsidy off the public resources of clean air and water. If everyone burning a fossil fuel were merely required to pay for the appropriate amount of CO2 scrubbing to maintain the atmosphere, and all the other environmental damage was ignored, clean power would be the biggest industry in America in ten years.
Bob is a good guy and an excellent engineer, but he stacked the deck for this one. As I mentioned before, reducing current launch costs by an order of magnitude is forseeable within the very near future. Designs that could, for large launches, reduce it by two orders of magnitude are clearly within the reach of current technology. If launch costs aren't down by a factor of 100 by 2050, it'll be because we've been sleeping on the job.
See the sci.space.settlement FAQ for a detailed analysis of this and some other concerns, although they're oriented towards a slightly different problem. At any rate, Bob also shoots down SPS by requiring massive orbital colonies to support the power generators, a demand that is, to say the least, arguable.
Speaking of large man made objects in space, what about all of our junk from previous NASA endeavors left orbiting (or left with the hope that they would burn up eventually)? What about all of the micro-meteorites that are moving fast enough to slice a car in half?
By putting a huge array of solar-panels in space, you've just created an object with a considerably large surface-area to mass ratio. Therefore, the probability of it getting hit, damaged, or even destroyed by speeding space junk is all the larger.