Paul RakoTechnical Editor Paul Rako looks at analog technology in power supplies, interface, the signal path, and life in general.


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Friday, July 25, 2008

Solar power in space, a really stupid idea

Jul 25 2008 9:42AM | Permalink | Email this | Comments (36) |
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The New York Times has an article about solar power satellites (SPS). This is where you put a few square mile of solar panels up in space and then just beam the power down to earth with microwaves. This idea was so loony and so farcical on it’s face that I about had a conniption fit. Well, this is the great thing about the Internet. See, the New York Times allows comments on its articles and they soon had six pages of comments, many from engineers like ourselves that pointed out how incredibly stupid this idea was. A few years ago the Times would have received a dozen letters critical of the article and maybe published one or maybe killed them and nobody is the wiser. Now they get 143 comments, mostly con, that suddenly appear and the whole world can see how absurd the proposals in the article are. And I love the researcher that comments, “What would it hurt to spend about 100 million on further research?” Well not his house payment, but we peons have better things to research with our tax dollars. Like why the seam of my blue jeans’ legs curl up when they come out of the dryer. I always wondered about that.

Just as sad, of all the comments with good reasoned analysis, the comment the Times put on the first page in a little highlighted box was:

"Energy from space really is one of the crucial 'three pillars' of renewable electricity, along with wind and thermal solar farms." Dr. Paul J. Werbos, Arlington, Va.

That was pretty unbelievable to me, but just look the first paragraph of the article itself:

As we face $4.50 a gallon gas, we also know that alternative energy sources — coal, oil shale, ethanol, wind and ground-based solar — are either of limited potential, very expensive, require huge energy storage systems or harm the environment. There is, however, one potential future energy source that is environmentally friendly, has essentially unlimited potential and can be cost competitive with any renewable source: space solar power.

This is a flat-out lie. It’s a lie in so many places it hurts my teeth. Sweeping all the alternative energy sources under the rug, without looking at the complex analog tradeoffs involved is an affront to reason and decency. That is a bad enough lie. But to then follow that absurdity with the assertion that space solar power is somehow economically possible and environmentally friendly is complete madness. Now I am going to give some sources you can read that prove beyond a shadow of a doubt that this proposal is clinically insane, but first I wanted to share an epiphany I had. Paul’s epiphany came about 5 hours into a wasted Thursday night where I should have been in downtown San Jose having fun at the free concert. Instead I spent all night reading all the sources I could find regarding SPS. I am embarrassed because it took five hours to realize something that was plainly stated in the comments to the article that I read five hours before. Someone pointed out that the technology of this proposal did not matter. This space-panel microwave gizmo was also a weapon and it would be politically impossible to deploy it.

Wow, hours of my personal time down the drain before the epiphany. The epiphany was that this thing was exactly that, a weapon. That is why NASA researched it in the 1980s, that is what all the feasibility studies were about and that is why it is being floated out there right now. The military industrial complex wants to test how stupid we are. If the American people are dumb enough to believe that solar panels in space is even the slightest bit possible then they can use that cover as they do what they really want to do, make a death machine. The images of the Terminator movies and SkyNet are too chilling to even contemplate.

Now there may be some Pollyanna types that think our wonderful government is way too nice to ever try and develop a death machine. Sorry, for those of you that think the United States Government is more like a fluffy little fabric softener sheet tumbling around the dryer, making everything silky smooth and smelling fresh, well, news flash: Governments are about coercion. Force, killing, jails, waterboards, and the rest are the essential nature and job of the government. Sure they hand out a bunch of middle class entitlements to stay in power and keep the sheep bleating happy sounds, but the core nature and purpose of governments is forcing people to do things. Most of the less naive among us are OK with that. After all, I am sitting on a lovely little parcel of land that was stolen from the Mexicans, who stole it from the Spanish priests, who stole it from the Portuguese priests, who stole it from the Indians, who stole it from each other for 10,000 years. Works for me, I just planted some cactus in the front yard. Of course I will be complaining about the effective 45% tax rate we engineers have to suffer till the day I die, I hate the government forcing me to do that. But I will just kind of skirt around the benefits all the killing and mayhem provided me. After all, I deserve a happy little Domicile of the Future here in sunny Sunnyvale. I have a title to prove it is all mine. I am glad my government stole the land for me, just like I am glad Burger King shoots a rod into a cow’s head so I can have a tasty burger with none of the emotional baggage. Who wants to drive a nail into Elsie’s skull?

OK, still doubtful that NASA, our beloved space program would try to fund a death machine under the cover of alternative energy? Well, you didn’t have the benefit of working at several military contractors, like I did. When you work at those places you invariable meet people who think in military terms. One of them told me twenty years ago that the entire space program was a military operation. I was incredulous. He patiently explained. See, warfare has always been about controlling the high ground. If you could control the plains while the enemy was in the ditch, you won. If you controlled the hill while the enemy was on the plain, you won. If you control the mountain while the enemy is on the hill, you won. If you controlled the airplanes while the enemy was on the mountain, you won. OK, news flash, live at five, film at eleven: If you control space while the enemy is in an airplane, you win. The military types at those military contractors told me what was already pretty apparent—that there is no sensible scientific reason to put people in space. All the science is much much much cheaper if you don’t need to launch life support. Sure astronauts do maintenance on the Hubble telescope, but for what we spent developing the shuttle, especially when you count the dead astronauts, we could have sent up a dozen Hubble telescope and just let the broken ones fall out of orbit. The space station is a prototype AWAC and this solar-power death-machine is a prototype AC-130. And remember, for the $100 billion we spent on the space station, every American household could get 952 dollars for gasoline.

Trust me on this one; this solar power in space stuff is a military research project to make a death machine. Then things start to makes sense technologically and sociologically. Some of the most severe limitations of the system go away when it is a weapon. There is no need for constant maintenance since it is used intermittently. There is no need for a geostationary orbit, you want to be able to kill people anywhere, including and maybe especially inside the US borders. Keeping us in control is just as important as killing foreigners. Heck you don’t even need a geosynchronous orbit. You can put the death machine in low earth orbit. That saves a huge amount of cost and dispenses with fantasy proposals like the NASA guy that said we should build them on the moon and then bring them down. I started to ask myself if these idiots have even been in a semiconductor fab, much less one on the moon, but see, then I realized, Doctorates are not stupid. The government needed some fantasy cover story to keep the research going in the face of the fact that the power would cost not 10, not 100 not 1000 but about 10,000 times more than terrestrial based power of any form.

Ok, sorry to all you hard-core technical types for that diatribe, but I did not want you spending 5 hours researching this like I did without understanding this is death machine proposal, not an alternative energy proposal. Here are the sources. The URSI (Union Radio-Scientifique Internationale) has a nice web page as well as an identical pdf that debunks most of the SPS proposals. They seem to make an error when they say you need 10,000m2 to receive 14GW solar flux. With 1.37 kW/m2 solar flux I see it as a million square meters, a solar panel 1 km on a side. The 14 GW is reduced to 1 GW by the 7% system efficiency they describe. The paper is very neutral, unlike some of my ham buddies that would just say; “You want to beam a gigawatt of RF energy into the atmosphere, and then build a whole bunch of them? Are you out of your f*(&^ing mind?” This paper has references, both pro and con and it is the con ones that have the good reading. One good resource is S. Fetter, “Space Solar Power: An Idea Whose Time Will Never Come?,” (pdf). Where you might want to start is just read all the comments in the NY Times article. Read all 6 pages.

I will try to summarize the basic arguments:

SPS Pro
  1. Solar flux density in space is 1.37 kW/m2 as opposed to 1 kW/m2 in Arizona at noon.
  2. The solar collector can work all day since a geostationary orbit is 24,000 miles up, directly over the equator, and the earth does not shadow the collector. There are no clouds in space.
SPS Con
  1. Economics. This is just madness, bat-shiat crazy stuff if your goal is to generate commercial electric power. Launch costs, maintenance costs, safety costs are, literally, astronomical.
  2. Politics. Like the commentator said, this is a weapon, and by the time we develop it China will have the technology and international standing to nuke Cape Canaveral to keep us from putting it in space.
  3. Technology. The end-to-end efficiency is 7%. The URSI used 13% solar panels, and Sunpower’s are 17% and they promise 22%, but the URSI article points out you would want to use amorphous silicon for the weight advantage and there’s your 13%. The inefficiency of the radio beam means the microwave inefficiency, easily 400 MW on a 1GW installation, would directly heat the atmosphere. And we were doing this for what, global warming? The solar wind damages the panels; they will have to be constantly replaced. One commenter to the article worked on a study and pointed out we would have to launch every two weeks for years just to get one in space and then just keep launching them every two weeks for maintenance. Making the phased array antennae and receiver is a huge technological challenge. Since it is too big to prototype on earth you have to count on computer simulations. Yeah, this should end well.
  4. Safety. You are trying to aim a microwave beam at a 4-kilometer spot from 24,000 miles up. What could possibly go wrong?
  5. Ecology. You will vaporize any bird or animal that gets into the beam. You will punch a hole through the clouds 24/7 where the beam comes down. Who knows the affect on the ionosphere or the earth’s magnetic field?
  6. Security. For a power plant the installation has to be in geostationary orbit. That is directly above the equator. So if you beam the power straight down the receiver has to be on the equator as well. In addition to the security nightmare, you will still have to run wires from the equator to wherever the power is needed. Else you have to obliquely aim the thing and that is a real mess.
  7. Fantasy. Come on, even non-technical people have to see that putting up factories on the moon, to save money making this thing, is complete BS. Ignoring the maintenance issues and real-world engineering for ivory-tower science-fair nonsense is equally fantastical.
  8. Health. Having all these microwaves beaming around may cause cancer or other problems. If it comes down to 60 Hz or microwaves I will take 60 Hz any day.
  9. Interference. Pumping gigawatts of RF into our atmosphere is sure to ruin a lot of radio communications that operate at nine orders of magnitude lower power levels or more. The URSI report points out that radio telescopes would be unusable. In addition all you RF folks know that there will be side-lobes and spurs and harmonics on the 2.4 or 5.8 GHz so there will be huge swaths of higher frequencies that will now be unusable for radio communications since the gigawatt space power stations are blasting them out of the air.

I guess there are other objections but the sun is coming up and I have to get to work, real work with a real job at a real company that maybe the NY Times should use to vet incredibly stupid stories like this. Our government is using the Times like a useful idiot, having them print and lend credence to an idea that can only be used as a death machine. Now, I am not saying we should not have a space-based death-machine. In a world where unemployed dirtbags fly jetliners into office buildings, maybe a death machine that cooks people like Jimmy Dean pork sausages that have fallen into the campfire is a great idea. And it will leave all their buildings and stuff for us to use afterwards. But if we are going to discuss this as a free people and pay for it with our taxes, we have to make clear we are researching a death machine and not alternative energy.

One last thing. I hope nobody thinks I am against solar power. I wrote a blog that pointed out that solar is still not economical but I made an error in my econometric model. See I figured the cost of electricity as 13 cents a kW/h. I figured that was generous since that was California power rates and that most people not in California pay way less. Well when I wrote that I was paying electricity for the Office/loft/warehouse/shop/consulting-place megaplex. That was industrial power and was a flat rate. Now that I am at the Domicile of the Future, I got my first residential California electric bill a month ago and, yeah, we pay 13 cents for the baseline amount. But since I have air-conditioning, I paid 32 cents/kWh for a good chunk of electricity. So I am all for solar power if it makes economic sense (without government subsidies, I really do not think it is moral to tax my neighbors so I can have a solar installation). Well it seems now that the thing is to use solar to keep your house from exceeding the 13-cent baseline rate. I will scratch my head and work up another analysis to see if solar panels pay out on that basis.

Meanwhile I do have a couple of ideas. One is for a solar installation that is not grid-tied. I wonder if any one makes a system where the panels just power a dc motor that runs a heat-pump. Then I can have air-conditioning (or heat) and not have to use PG&E. The other idea is to have the panels hinged down the middle on the peak of my roofline, which runs north-south. That way I can get some benefit of tracking in a gross way. In the morning a servo or timer can plop the panels on the east-facing roof, then maybe track the sun till noon, where the panel will look “balanced” on the roof peak, and then follow the sun down so that the panels end up lying against the west-facing roof. Even if they did not track but only flopped from one side to the other at noon, it would provide more power than if they were fixed to the roof. If anyone knows of any hardware like either of these ideas, let me know.


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Reader Comments


at 7/25/2008 2:01:55 PM, Poppy said:
I remember the questionare back in the 80s. At that time I came to the same conclusions you did - It was a weapon, plain and simple. The real advantage is that you could fry nearly anybody, any time and they might not even know how it happened. I don't trust my government (remember they are politicians) with that kind of power.

at 7/25/2008 2:16:43 PM, Grammar Freak said:
You do go on, don't you?

at 7/25/2008 2:20:37 PM, Randy said:
All power systems are subsidized at some point by the government. Are the import duties on oil sufficient to ensure a supply from a Midevil empire or other hegomonists? Where do all those nuclear engineers come from? Outerspace or the U.S. Navy and Pell Grants. Who pays for the right of way of the transmission lines, or suffers eminent domain when land is taken for power plants. And finally, there is the multiplier factor of economic benefits from solar that do not directly translate into the cost benefit model of most incomplete econometric calculations. Just look at the cumulative negative impact of $700B annual outflows for oil vs. giving every man, woman, and child a free 2kw solar plant. The 2kw plant looks cheap by any measure. So get off your high don''t tax me horse and see the reality of an International Market Economy.

at 7/25/2008 2:25:11 PM, Dallan said:
The "international" space station is a prototype AWAC....really? Then it must be a multi-government (including the Russians) conspiracy. Come on!

at 7/25/2008 2:45:23 PM, Solar Geek said:
Hey, Paul...you might really like those new Emcore 42-45% efficient CPV cells...I'll bet the beam-power-from-space crowd can't stand it.

at 7/25/2008 2:46:29 PM, JMan said:
I agree with you except on one point. The Mexicans did not steal the land from anyone because they are the native "Indians". Look up the Uto-Tanoan-Aztecan language family. As far as the weapons, you are absolutely correct. I volunteered for Vietnam and then worked for various weapons manufacturers. I''ve worked on the AC-130, U2 and other black programs including a UCAV drone in the seventies. The SR-71, Stealth, and Aurora existed for years before the government finally admitted to their existence. As far as the Hubble is concerned, big deal, there are bigger, better telescopes in space and they are all pointed DOWN, looking at us. That satellite that was shot down recently was another interesting event. Many satellites have come down, why did that one represent such a threat? Well, besides testing a weapon system to shoot down satellites, this one must not leave any debris to analyse. Think of your solar panel, microwave death ray. Do you really need all those solar cells or do you just need a small nuclear reactor? Remember the strange lights hovering over Phoenix? The light spectrum was so narrow that some people thought they had to be extra terrestial. No, just testing a new night vision system in an urban environment. Heck, even drug dealers and terrorists have state of the art night vision equipment now. The feds have a new system that only they have receptors for. As far as a Jimmy Dean sausage, dirt bag cooker, we already invented the neutron bomb. Corporations doing weapons research on the taxpayer dime. They then own the patents and make all the profit. Just shut up and pay your taxes.

at 7/25/2008 2:59:33 PM, James said:
This is perhaps one of the most maddeningly confused articles that I''ve read on the topic of space solar power. Leaving aside that the clear majority of the article is dedicated to the author spouting his quirky political philosophy, which seems to be a mixture of paranoia and ill-digested libertarianism that is far too common amongst many techies these days, the author''s technical points are themselves contradictory. The entire "death-ray from space" notion is even goofier than the idea of developing civilian power. We already have the capability of putting megatons of explosive power wherever we want it, with astonishing speed. It''s hard to imagine some fanciful death ray giving us more destructive power. Well, you might say, a death ray from space would offer some high level of specific precision that a nuclear warhead wouldn''t. I''m not sure that reducing collateral damage is a bad thing, but even it were the author has assured us that such precision is somehow pie-in-the-sky lunacy when it comes to directing power to the Earth for civilian purposes, where he seems to insist beaming power to a 4km spot from 24K miles up is just beyond us. The author insists that the manned space program is just a cover for a sinister military purpose, fantastically claiming that there is "no sensible scientific reason to put people in space" and goes on to insist that the International Space Station is a prototype AWACS and space solar power is a prototype AC-130. The real question is why the author thinks you need people manning this kind of stuff for a military purpose. With the increasing movement towards unmanned platforms I''m not sure why the author thinks there is some military necessity in space warriors floating around up there.

at 7/25/2008 3:15:05 PM, RealScience said:
Regarding solar, I'm happy to hear that you are all for it when the economics make sense (which is when if all subsidies were equalized on all forms of electric generation, it would be at parity for the power it generates (good for peak, harder for base-load). As for your own roof, what you are describing is a one-axis tracker with your roof ridge-line as the pivot. That's actually fairly easy to do, as the weight is modest. The real key is to preemptively lock the puppy down to the roof when it STARTS getting windy!

at 7/25/2008 3:18:13 PM, RealScience said:
Paul, while you are right on some points, you are way off on others. So what if 40% of the power heats the atmosphere - in a coal-fired power plant 60% goes directly into heating the atmosphere, and then the CO2 emitted traps that much heat again every year for hundreds of years. In your rant you miss OBVIOUS things like this, throwing you off by more than a factor of 100. There are plenty of architectures that make it feasibly except for one gaping hole - the launch costs. On that you are currently correct, at today's launch costs there is no way the economics fly. As for the government and weapons, there are a lot easier ways to fry someone than to launch huge weapons into space and maintain them for decades, all for a weapon that can only focus down to a mile or so with an ground-intensity less than that of sunlight. Big space solar panels to power a big laser might be a weapon, but the microwave beam part would barely keep you warm on a cold night! As for Ph.D.s for cover, Ph.D.s can be very smart in one area and very stupid in others, or simply not think about areas outside of their tiny specialty. Manufacturing on the moon is indeed lunacy at this time. You always raise some good points, but then you rant on about points that you don't understand and dilute the impact of your valid points. Are you simply trying to match the 'grain of truth in a mountain of rhetoric' that you complain about from both the eco-freaks and the ultra right-wingers?

at 7/25/2008 3:21:09 PM, Michael said:
I can't believe I finally agree with Paul on something: space-based power generation is stupid. Having said that, the rest of your rant is just that. Meanwhile, could you please tell me how us poor folks, including Ph.D's in science and engineering can get in on that 45% tax rate? Even though we are pretty well set in our Silicon Valley high tech company, we don't make that much to get in that bracket. BTW, it's good to know you are from San Jose, just as I am. So I know all those previous blogs on global warming are half-truths, distortions, and misinformation. You are experiencing the same weather patterns I am. When we're in a drought and you claim otherwise, we know you have your head in the sand.

at 7/25/2008 3:40:07 PM, Stiggle said:
OK let's simplify and lower the cost of the part in orbit. Just send up an huge inflatable solar reflector to beam and concentrate the energy down to earth... I still wouldn't want to live on the same side of the earth with such a powerful accident ready to happen even if it was never used as a weapon (although it will be used as one, terroist or otherwise!!) Got to laugh.

at 7/25/2008 4:19:25 PM, Dan said:
If you visit the IEEE website at ieeexplore.ieee.org and search "solar power" and "space" and "microwave", you will get 51 results. I only read one, "Space solar power station (SSPS) and microwave transmission (MPT)", but this researcher was serious.

at 7/25/2008 4:33:49 PM, James said:
RealScience wrote: "Manufacturing on the moon is indeed lunacy at this time. " Pun intended?

at 7/25/2008 8:04:35 PM, mike said:
Space-Based Microwave Power. It will happen, if not in the USA then in Japan, China, Russia, or Europe. I sure Columbus had the same arguments against him but look where it got him. You need to pull the blanket over your head and go back to bed because none of your facts make any sense ?

at 7/25/2008 10:23:03 PM, Tornado Zapper said:
A few years ago I attended a talk at an aerospace conference that proposed to use the focused microwave beam from a Space Solar Power Station to disrupt tornadoes. I raised the issue of potential weaponization and the presenter cheerfully replied that "it could have been used to cook Saddam in his bunker." Concern as to whether or not to build one is moot. The military already has plans to field a "small test version" ostensibly to provide rapid power to troops in the field. Care to carry an aluminized umbrella?

at 7/26/2008 2:26:41 AM, Raffaele Ercole said:
This idea is not new. I remember reading about it in my (then) very uncertain English when I was about to graduate in Electronics over 30 years ago. It was called SSPS and portrayed some advanced solutions like solar panels with an integrated klystron on their back. A ground receiving antenna (called rectenna) over a 7 km square to collect energy. The huge area size was required to reduce the microwave density in the beam. The article even considered the impact on birds and of course aeroplanes. It did not look too baloney to me, but those were the times of Kubrick/Clarke and sci-fi. Much has changed since then, but the issue of conveying that energy back to earth is still the may problem. If we could address that satisfactorily, the idea would not be stupid at all.

at 7/26/2008 8:29:24 PM, John said:
Commenters James and Dallan: Please let me guess - either you''ve never worked in the area of military space systems at all or you are deep in it. I''m guessing the former. That''s fine

at 7/27/2008 8:22:08 AM, meredith poor said:
To amplify Paul and Solar Geeks point, quote pasted from Emcore news release: "Developed in conjunction with the National Renewable Energy Laboratory (NREL) and the --->>>Vehicle Systems Directorate of the US Air Force Research Laboratory (AFRL)<<<---, the IMM design is comprised of a novel combination of compound semiconductors that enables a superior response to the solar spectrum as compared to conventional multi-junction architecture."

at 7/27/2008 8:25:29 AM, Meredith Poor said:
The solar flux numbers appear to be wrong, the flux in space is somewhere between 2.5 and 3 kilowatts per square meter. About half of the solar power arriving at earth is absorbed or scattered by the atmosphere before it reaches ground. At the equator, a high-noon flux is about 1.3 Kw. In the temperate latitudes flux is about 1000 watts.

at 7/27/2008 8:36:43 AM, Meredith Poor said:
One person's weapon is another person's tool. I can make a weapon out of a front end loader, a Boeing 757, or a cell phone. I can use a nuclear bomb to extract natural gas from dense rock, use a cruise missile to clear a rockfall that has dammed a remote valley, and use an aircraft carrier to fly in relief to tsnumai victims. The US is currently working on some kind of air breathing suborbital missile that could whack a belligerent leader from 3000 miles away in a matter of 20 minutes. While we work on that, we improve our computer chips, jet engines, materials, and other technologies, most of which get far more use in constructive purposes. It's convenient to pass judgement on the motivation for the R&D, but such things end up diffusing out into the general technology pool, where moral application spans the spectrum from evil to angelic.

at 7/27/2008 8:42:46 AM, Meredith Poor said:
As far as the space based power array goes, I would find such a device more useful for driving ion-beam or passive propellent spacecraft than for powering earth. Aim one at a Mars probe as a power booster, so that it could get there in a matter of weeks instead of years. Or situate on in Mars orbit to power a Martian base. In that situation no one would care about birds or airplanes. As far as beaming mw microwaves to Earth, don't even think it!

at 7/27/2008 8:43:56 AM, Meredith Poor said:
The "MW" in the previous post means megawatt.

at 7/27/2008 9:33:08 AM, Meredith Poor said:
Some of the issues raised in this post beg the question. Why do politicians and military planners even authorize and fund various weapons systems? One can look at ancient history (Aristotle), Renaissance (Leonardo da Vinci), or the Napoleonic wars (Congreve (rockets)) to see the engineer as the promoter of the development and deployment of death machines. One builds such machinery out of a sense of paranoia, and paranoia is, needless to say, simply imagining all the things people can or will do to you. This imagination, in turn, is the foundation of all human creativity. To hear an engineer ranting against the proclivities of government for terrorizing foreign and domestic populations, one has to ask, how did these people (military intelligence, oxymoron) even know such things were possible?

at 7/27/2008 12:24:32 PM, MG said:
We''re all better off if we take the money, distribute it (or keep it in the first place) and each of us puts a solar panel up at home. Oh, and by the way, it''s been my experience that governments tend to ask for forgiveness rather than ask for permission, so I''m sure the money has been spent and now they are trying to think of an excuse...

at 7/28/2008 4:25:36 AM, James, UK said:
Didn't Ernst Blofeld have a handle on this thirty years ago ? I saw a documentry called 'Diamonds are Forever' highlighting the military potential of solar energy back in the 70s. Luckily our plucky intelligence serviceman 007 sorted him (and his evil henchmen) out good and proper.

at 7/28/2008 7:13:52 AM, Spring is BACK said:
Meredith and Stiggle have good points: 1st, just do it with mirrors. Converting to RF is WAY more expensive. 2nd, if a weapon can be developed, it almost certainly will be. If we don''t, someone else will. I''d rather that WE have it first: Even if I''m not always too thrilled about the US gov''t, I am thrilled less about almost all the others. I''d also point out that this is merely a stepping stone in humankind moving into space, in a significant way, which we need to PUSH. The longer we delay, the greater the chance that Mother Nature will punch our number, for good. THAT''S the bottom line reason for a manned space program (as puny as ours is.)One other point: This can be a truly "thermally neutral" power source, in the sense that, up to a point, this can just be a redirection / redistribution of sunlight, with no net gain of sunlight to the Earth. It is true that used on a very large scale, one would have to be careful about effects on the weather, and such.

at 7/28/2008 7:24:07 AM, Spring is BACK said:
Michael needs to add up EVERYTHING he pays the gov't, not just Federal income tax. That's right, add in SS (both the contribution of you and your employer, because in the end, YOU are paying your employer's contribution too - think about it!) Add ALL State and local taxes, fees, etc. Even a person of modest income can end up paying 40-50%, particularly in some states. I did this for myself several years ago, based on my then income of a little under $45k (and then single filing status) and discovered just over $20k went to the gov't, in some way, shape, or form.

at 7/28/2008 7:42:16 AM, arclight said:
Paul and others: Government is not inherently evil, nor is it inherently good. It''s government. How good or evil it is depends in a very large part on how it is structured and how actively it is managed. Some governments are structured to enslave their populations, in whole or in part, or to enslave other populations. Some governments are structured based on a wholly unrealistic view of human nature (e.g. everyone is basically good, etc). Our government was structured to provide as much freedom as possible to the citizenry, and was based on a pretty shrewd knowledge of the evil that humans can do (that''s one reason for the checks and balances). With that freedom, however, comes a cost. Our government is the most expensive form of government that has ever existed because it is structured to depend on and require (a) the active self-regulation of the citizenry (which means working against their own natures, in many cases), and (b) the active participation of the citizenry in the process of government, in ways that cannot be purchased with money. If the citizenry will not regulate their own behavior (e.g. "if it feels good, do it"), or if the citizenry will not participate in the processes of government, this form of government will ultimately fail and degenerate to some form of tyranny. Are we there yet? I don''t think so, but... With regard to satellite-based solar power, I agree...it doesn''t make a lot of sense. Far better to put the solar panels on the ground. Side note: This and other previous posts suggest that we are looking for the Silver Bullet to solve these problems. Why not instead look for a collection of small solutions that collectively solve the problems instead? In WWII we used plain old bullets to bring down aircraft, rather than expensive missiles. We shot a lot of plain old bullets, but we brought the aircraft down. Same thing here. Bring on the collection of small solutions.

at 7/28/2008 10:14:41 AM, W17053 said:
maybe you are overpaied, or where can I apply for Technical writing job? I believe the Microwave oven also came from the Space Program. How many other moral subsidies do you pay without flinching? Will you allow me to reduce my taxes by the amount of items that I think are immoral? You might try calculating your solar based off not just getting to the 13-cent baseline, but on what is needed to lower your usage to each step - this may yield a better payoff. If you don''t want to tax your neighbor for your immoral solar array, then pay for it in full like the off grip people (and groups) do. Ask Ed Bagley (sp?) how / why he did it. There is a group in Illinois that recommend a solar system that is just large enough to run your furnace, refrigerator, and 1 light for use in the North West winters (when power lines break); sorry, you may have to disconnect your AC unless you have a Heat Pump. You might want a 2-axis servo to change the gross height a few times a year to account for the sun''s angle (this was thought-of years ago with 3 settings: Summer, winter, and mid season using 3-fixed adjustments. The person would climb on the roof 4 times a year to adjust the tilt).;

at 7/28/2008 10:16:34 AM, W17053 said:
The beginning of my post was not transferred: 100 million is nothing to the Government. The seam of your blue jeans’ legs curl up when they come out of the dryer is because of the double material yielding uneven drying, and possibly that you have the setting too high and / or for too long. When can I expect my check? I have not yet attained the 45% tax bracket; maybe you are overpayed, . . .

at 7/29/2008 9:52:02 AM, DW said:
Peter Glaser first wrote of this in the late 1960s and I read his articles on the SSPS in high school and college in the 1970s. The key issues at that time were the same as today, although apparently Paul is unfamiliar with the past details. The issues are: 1) manufacturing and deployment cost. The SSPS concept is only practical if there is a substantial in-orbit and moon-based manufacturing economy. It was recognized from the beginning that Earth launch would be too expensive. 2) Safety concerns of the microwave beam. The power density in the beam isn''t too high, but even near the edge of the beam, there were and are concerns about short and long term exposure to those microwave levels, planes flying through the beam, etc. This also included levels under the rectenna (rectifying antenna receiver) since the concept was to have the rectenna mounted above ground, and the land below could be used for farming and ranching, since sunlight and rain would penetrate the rectenna mesh. 3) Weaponization. This doesn''t have to just be a high energy beam from space. I''ve read science fiction stories where the microwave beam from an SSPS powered a high energy laser in low earth orbit. 4) Microwave pollution harming radio astronomy. Radio astronomers were concerned about this. In the end, the lack of a space economy has been the holdup.

at 7/29/2008 11:56:08 AM, RealScience said:
Merideth - your 1.3 kW/m2 at the equator figure is for ABOVE the atmosphere, not for ground level). As for reflecting the light down from geosynchronous orbit, the light would spread to 220 miles across and so would be impractical. And yes this has been discussed in the '60s and '70s. There has been tremendous progress since then on the power transmission, and on the solar cells. Where progress has been lacking is on launch costs.

at 7/30/2008 10:46:19 AM, James Senft said:
Why did you single out "priests" as thieves of land? While the Spanish and Portuguese explorers mistreated the natives, taking their land and possessions, the historical record shows the missionaries repeatedly petitioning the monarchs who sponsored the expeditions to safeguard the rights and dignity of the natives. It was the missionaries who struggled to protect the natives against the actions of some of their own countrymen. That is why many of the natives came to respect and love the missionaries!

at 8/6/2008 8:22:31 PM, Zeke said:
Interesting. I always thought that the microwave idea was pretty out there myself. Hell, if you ever played Sim City 2000, one potential disaster would only happen if your built a certain type of power plant. ;) I got a better idea, and it involves an orbital tether. That'll kill several birds with one stone: dangers of microwave energy in the atmosphere and the inneficiencies involved with it, and the cost of launching is largely negated when you can send a cargo lift on up instead. Sure, it'll take a lot of research and development, but the potential returns are nothing short of bountiful.

at 8/21/2008 7:53:17 AM, Robert said:
The sun transmits to the earth 10,000 times the amount of energy being consumed in all forms. Receivers placed in geo orbit, where there is no weather or day/night cycle, can provide enough energy to run cities and industries without CO2 contribution or nuclear waste materials. Space-Based Solar Power is the industrial reason to settle space. Because of the diffuse nature of the energy beams to ground rectennas, and because of international and/or human extraterrestrial ownership, it is not a weapon of the accuracy or potency equal to other weapons already deployed or on the drawing boards of various skunkworks. It is a strategic asset similar to hydroelectric dams but not as reachable by terrorists. So, what's your prob?

at 8/22/2008 1:32:55 PM, Pail Rako said:
Well I thought I expressed my "prob" in the article-- "diffuse nature"? They are talking about beaming down a gigawatt. So if the receiver is 1000M2 that means the radiation flux is a megawatt per square meter. Do you have any idea how much radiation 1 million watts is? Your microwave oven makes 500 to 1000. To make the RF energy the same as the 1 w/m2 that solar energy is, you have to make the panel a billion square meters , or 100,000 meters on a side. Do you really think an antenna 100km on a side is practical? Since they are talking abut 2.4 GHz this will be absorbed by water vapor, directly heating the atmosphere. You need a thin beam so you can blast through the clouds. And that ground antenna is sure reachable by terrorists. This is just plain crazy. That anyone could see that as practical, even if it works as promised, is astonishing to me. I do like the tether idea, that would solve a lot of problems, but the power would still have to come down near the equator.

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