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Lunar Power
An Anonymous Coward cites this article on ABC News, excerpting: "...the world would have access to a limitless power supply. The moon receives 13,000 terrawatts of power from the sun. Harnessing 1 percent of that energy, he calculates, could replace all fossil fuel power plants on Earth."
By virtue of the size of earth, we ought to be getting more. Harnessing 1% of this is as good!
S
It currently costs $10,000 to get 1 lb of material into orbit. How much would it take to get it to the moon? One hell of a lot.
It's going to be a heck of a lot cheaper to burn money to make power than use the moon for a long, long time.
total nonsense. the receiving dishes would have to be large and would cost to much to manufacture and put in orbit. you'd be better off pursuing fussion as a source of energy. or why not build the solar cells on earth, or float them in lines of buoys on the ocean?
Apparently this dude has never put a marshmallow in his microwave oven.
--All your stolen base are belong to Rickey Henderson
Yeah, so uh what's so special about the moon exactly? Earth is practically the same distance from the Sun as the moon is distant from the Sun and isn't it a heck of a lot more efficient to just create a local satillite network instead of going all the way to the moon?
Or even better... just have it based, I don't know, on the ground? Once we come up with more efficient solar cells then you're all set...
1%, ok, i'll grant him that...efficiency of solar cells being what they are..... of course that means completely covering the surface of the moon, and then figuring out a way to transport the energy back to the Earth....
I'm out of my mind right now, but feel free to leave a message.....
The height of delusional techno-fantasy-masturbation. Come on people, let's think here. What's easier... Getting photovoltaic or thermal concentration arrays up into orbit at the cost of thousands of dollars per ounce and then shipping them to the moon, installing them, and somehow shipping back gigawatts of electricity to earth by radiation..
OR,
putting up photovoltaic or thermal concentration arrays on earth. On your house, your car, in the backyard, on fields, on buildings, on deserts, on woodlands, on fences, on anything that's flat, vertical, or in between, using unskilled labor and unsophisticated tools.
The answer, of course, is to use less energy period. But you can't strap a nuclear warhead onto efficiency, so let's just go with the space rockets to the moon plan instead. Durr.
C'mon editors. My cat could have figured out a better power scheme than this. Even the Hydrogren that is 20KM under the surface of the earth would be cheaper. New national level building codes where we force all new buildings to have solar panel roof tiles and solar colleting windows would be easier to pass by congress. Also, quite frankly, the guys that are still hacking away at cold fusion probably have a better chance of getting it all to work.
Damn I wish this was K5 so I could vote to dump this article.
Pithy, yet ultimately meaningless, phrase expressed with gusto!
You don't take photovoltaic cells to the moon, you build a factory on the moon and make the cells there. Just about everything you need is there: water, minerals and even some things that you don't find that often on Earth.
This is probably as far beyond our immediate capability as getting to the moon was to people of the 1940's - just a matter of time, money and will. The latter seems to be the most lacking.
Washington, DC: It's like Hollywood for ugly people.
Everything posted before this seems to knock this idea.
Granted it's not the best - people are letting other current problems stand in the way.
So, let's recap:
Lower the cost of getting things in orbit.
Make better working solar cells.
Costs too much [for whatever other reason].
Of course we could change these things. If my local power plant could take in some money for investing in such a crazy system we might actually see something like it.
Maybe it would be better for other situations like storing emergency power or making batteries for space craft....
Get your Unix fortune now!
Whay happens when there's a cloudy day on earth - which is more often than not...
Anyway - some of that energy will leak into the atmosphere and will result in heating of it.
Other problems - How about jets trying to avoid the wandering microwave beam paths - unless we we can somehow narrow down the beam to an incredibly tight small area. This seems unlikely to be able to get this sort of precise control.
I swear we've seen this idea multiple times before on slashdot...
..........FULL STOP.
I don't think that's much of a point, as it's not universally agreed that putting a cell phone microwave emitter to your head is a safe thing. The point I'd make is, well, McDonalds isn't killing you, is it? Bring on the microwaves!
One thing you're forgetting: At *most*, only half of the moon's surface would be struck by light from the sun. The surface area of the moon is ~ 37,800,000 km^2 (let's just use your figure of 38,000,000 km^2 for argument's sake), so chop that in half gives you 19,000,000 km^2. 1% of that is 190,000 km^2... still a hella large area to cover.
:)
The other point is that they don't mention how they arrived at that 13,000 terawatt figure... is that the average instantaneous energy levels? Maybe it's the annual cumulative total? These, and a variety of other factors, influence how much of the actual surface area would need to be covered in solar panels to attain that "1% harnessed" figure.
This is still a massive undertaking, and has "vapourware" marked all over it. $150,000,000,000 (or more!) for the project to break even? Ouch. Give me the money instead!
Quoth the caption:
A U.S. soldier scans the horizon as the moon rises behind him in Kandahar, Afghanistan. A physicist claims solar energy reflected from the moon could provide endless clean energy
Do they just have stock footage of Afghanistan lying around? Is this the best moon picture they could come up with?
Maybe they just searched through the pictures lying on their desk, till they found one with the moon in it. We're lucky we didn't get a snap-shot of the author's poodle with the moon in the background.
Yes, it would, but not nearly to the degree that it would affect visible light. The frequency that power is transmitted back at can be chosen such that weather does not affect it, etcetera.
Microwave Power?...
Sim City 2000 Anyone?...
Where the hell are my Arcologies?
...would have to be a no-fly zone. Come to think of it, it'd have to be a no-pigeon, no-duck, no-eagle and no-butterfly zone too.
I don't think any of these uwave links will ever get built for one reason: NIMBY. (Not In My Back Yard).
Now, maybe you could convince some desparate 3rd world nation to receive, but that's not where the power is needed now is it? So you would just compound the transmission problem. I think they are better off using the power right there on the moon to drive energy-intensive manufacturing processes that produce small products that can be easily shipped back to Earth. That way, you free up energy resources on Earth without having to fuss about how the power is transmitted. Synthetic diamond production perhaps? Then of course there is the potential of mining the moon and running electric smelters up there, but it's probably only practical for certain rare commodity metals. How much platinum and gold is on the moon?
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
Nikola Tesla.
And Tesla had the right idea.
Harnessing 1 percent of that energy, he calculates, could replace all fossil fuel power plants on Earth."
The actual quote said, "Harnessing 1 percent of that energy, he calculates, could power up to four Intel Pentium-4 processors AT ONCE!"
--
"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
Should we use the moon for our power needs, or...
should we BLOW UP the moon
If tits were wings it'd be flying around.
"The moon receives 13,000 terrawatts of power from the sun... (bla bla)"
Why on Earth (pun intended) would we need to go the Moon for this?
Doesn't Earth get a healthy amount of energy from the sun as well? Would be surprising if it didn't. Clouds? They aren't that big of a problem. First, they don't cover 100% of the solar rays. Second, if the cells cover 1% of Earth's surface, that would be enough to get continuous energy IMHO. And, of course, you'd like to place most in sunny areas like deserts.
The big problem is to make effecient solar cells that cover 1% of Earth's surface. A pretty big area indeed. And make everyone agree with that it's ok. But I guess it would still be easier than going to the Moon for this.
Also, who's gonna pay?
Beware: In C++, your friends can see your privates!
So, the moon receives 13000TW of power, and we only need 1% of that? Let's do a little math eh...
Solar cells are at best about 20% efficient. For the sake of my argument, that's the number I'm using. The argument stands even if you could imagine getting 50% efficiency from the falling sunlight.
They would need to cover 1% of the lunar surface on BOTH sides of the moon, because only half of the solar panels would be in sunlight at a time.
They would need to cover 5% of the surface, because the cells are only 20% efficient.
Combine those two problems, and you have 10% of the surface of the moon covered in solar panels. Add another 5% because not every portion of the surface is suitable for placing panels. Multiply the result (15% of the lunar surface covered) by about 1.5, to make up for the transmission loss from the moon to earth, and through the atmosphere. Result... over 20% of the moons surface, its TOTAL surface both visible and non, covered with solar panels to get that 130TW the author stated.
Imagine the moon with a bright shiny ring of solar sails all along the left and right edge. If you can't hear every environmentalist and presevationist crying out simultaneously in anger, you are deaf.
"I will trust Google to 'do no evil' until the founders no longer run it." Hello Alphabet.
Sure.
Even a Dyson sphere seems more realistic :)
The Raven.
The Raven
Imagine how much energy must be shining on the Earth. Maybe we could harness that. Wait...
Donate background CPU time to fight cancer.
Second - getting the energy to where it will be used. This isn't particularly silly, since the energy could be used to manufacture something on the lunar surface (eg. satellites) which doesn't need to go all of the way home. Manufacturing processes like vapour deposition would work well there on an enormous scale - but at current scales it is a lot easier to use vacuum pumps.
Now the problem comes in ... Earth is rotating. The moon isn't in an equatorially geosynchronous orbit and eventually either the receiving dishes would need to be moved or the transmitting dish on the moon would transmit enough microwaves to eliminate life as we know it for a few hundred meters around its target. If you fear the cellular phone radio waves.... think sticking your head into your microwave in the morning instead of coffee.
People have discussed the idea of transmitting power before. Heck, Russia built a solar reflector to light up their northern lands. It's feasible, but being able to protect Earth from a microwave disaster would be EXTREMELY hard.
Ever need an online dictionary?
Oh gosh no. It makes perfect sense. We all know that the war against Afghanistan is to provide American Oil Companies with a pipeline from Turkmenistan to Pakistan". The photo is just one reporter behind enemy lines at Disney trying to get the truth out.
It's going to be a heck of a lot cheaper to burn money to make power than use the moon for a long, long time.
Why even make money to burn it? We can conserve our energy by not even manufacturing the crap and we'd save the trees.
We could, however, burn cow manure and help to erradicate those ugly landscapes outside Area 51 where cattle was once raised that have been littered with pies. (Seriously, the area was big on cattle a while back)
x
Ever need an online dictionary?
You're absolutely right WRT how you'd actually do this. However, I remain unconvinced that, when compared to terrestrial solar cells, the smaller quantities of cells required outweigh the stupendous cost of setting up lunar production facilities and supporting the lunar staff to maintain the system.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
Um hello to all the fuckheads at ABC: If the moon receives that much energy, and the Earth is 10x (or whatever) bigger than the moon, I'd bet it receives more energy from the sun (even accounting for all that is scattered by the atmosphere) and would be just a wee bit easier to capture. Let NASA spends it's billions (oh wait, Bush is in office...) on important stuff, like say that little project that is billions overbudget right now.
Kurdt
I'm not anti-social. Just pro-technology.
On the cow manure idea:
A new 750-kW power plant at Tinesdale Farms in Wrightstown, WI, is the first in the state to be powered by cow manure. The facility uses a "digester" to convert the manure to methane, which is then burned to generate electricity. Ag Environmental Solutions, LLC (Wrightstown, WI) owns and operates the facility, and Wisconsin Gas/Wisconsin Electric is buying the power and selling it to its customers. The manure comes from 1,800 cows at Tinesdale Farms, and it generates enough electricity to power 250 homes -- http://www.achrnews.com/.snippy./
Ever need an online dictionary?
And imagine what a mega weapon a moon covered with solar cells is. Just send the amazing energy as non-"harmless" to your country of favorite hate.
Man I'm happy this project is technically impossible, and don't tell me US army wouldn't have thought of that use of such an installation.
--
Karma 50, and all I got was this lousy T-Shirt.
First of all, that darn atmosphere absorbs a lot of it. Second, that's the energy that keeps you warm and feeds you (plants don't live off of love, you know).
The only way the moon as power source will be practicable will be if we move up there or figure out how to get that energy down here. Neither one is any easy task. You can pretty much forget about the first, and the second involves crazy plans with microwaves. What happens when the aiming device gets hit by a meteor, and the microwaves fry some poor shmuck? oops. Not to mention the amount of power that such a system would lose sending the signal through the atmosphere.
The only way I see space based power being practicable is with some sort of geo-synchronous elevator (the ones that are connected to the planet by a metal cable in sci-fi). Then you could put solar panels, fission/fusion or pretty much any other type of power plant up there, and just let the wires carry it down with a whole lot less risk than a microwave beam.
Don't hold your breath for any practicable space based power in our time, though.
BlackGriffen
Schwab
Editor, A1-AAA AmeriCaptions
"...the world would have access to a limitless power supply. The moon receives 13,000 terrawatts of power from the sun. Harnessing 1 percent of that energy, he calculates, could replace all fossil fuel power plants on Earth."
If we've got the same guy doing the calculating as we have doing the spell-checking, we're fucked. Besides, duh, it costs money to get something to the moon. Whats the rocket going to be powered by? Cash or rubberbands?
Cheers,
Bowie J. Poag
If we had the technology to do this on the moon, we could do it more easily on some desert.
Just for kicks and giggles, I thought I'd try to figure out how much area you'd need to cover to pick up that 1% of energy hitting the moon.
Radius of the moon: 6378.1 km
So the area of a disc of that radius is 1.278e8 km^2.
One percent of that is of course 1.278e6 km^2.
Lets construct our solar panels in a band around the equator, so that at any given time, 1% of the sunlight is being collected.
Treating the band as approximately a rectanle, so I don't have to think too hard, 1.278e6/6378.1 = 100.18 km
Now this stripe on a flat disc needs to be translated back to a band on the surface of a shpere. Approximating that band as a cylender, with hight 100.18km, and radius as that of the moon, we get approximately 4.0e6 km^2. For reference, thats tad less than half the size of the United States (9.629e6 km^2).
Build several (or several hundred) big (square-mile-plus) mirror-array collectors throughout the world (the dispersal reduces output fluctuation due to nightfall and weather).
Use the concentrated sunlight to generate steam which generates electricity which can be transmitted to grid subscribers, or to wet areas to generate hydrogen from easily available water (they hydrogen storage further reduces output fluctuations by acting as a chemical battery).
Use the hydrogen to run vehicles, electric generators for off-grid communities, and grid generators when sunlight is scarce.
The startup costs for this can't be any higher than for exploration, drilling, and refining of oil in the millions of wells we've sunk, and the resource costs aren't any lower than free gunk from the ground, and the maintenance can't be nearly as expensive as tankers and oil slicks, so this should work out fine until the sun quits on us.
--Blair
But why:
use photovoltaic
ship power back from the moon?
This was examined back in the 70s and there's a set of even better solutions. Two samples:
1) Put the actual collectors/generators in sync orbit:
Much shorter distance to ship the power.
Much greater surface area than the moon.
Negligible gravity (just tidal and station-keeping forces).
Alternatively: Use the L4 or L5 points - same distance from the Earth but still has the low-gravity and improved surface area factors.
Mine the moon for the bulk of the material, but use a catapult to launch it to orbit. (For L5 there's an orbit using one of the other L points as a lens that requires very little delta-v to perform the final injection, so the catapult does essentially all the work.) Smelt and construct it in orbit.
2) Build a STEAM plant on the ground and launch the pieces into sync orbit, where they're assembled. (Most of 'em go in reusable unmanned heavy-lifters. Much cheaper than the shuttle.)
Steam has the advantage that you don't need to do a lot of fancy processing. Just a turbine, mirrors, pipes, generators, condensers (a flat plate painted black at right angles to the sun or behind the collector mirror, with some more plumbing attached), and a trick microwave transmitter (plus an antenna farm in the desert.) You don't need much water, and it goes around and around without leaking out for decades or more, like the freon (or whatever) in a household refrigerator.
Tesla could have done it (except he'd have used VLF radio for the power feed, at considerable loss).
These proposals and several others were examined in detail by the L5 society (founded by the same Keith Henson who is now in Canadian exile over the Scientology thing).
NASA did a study on number 2, and came to the conclusion that it was too expensive. The L5 society then studied NASA's study and found an error: They'd done it in two steps:
- Design a plant.
- Design a set of vehicles to lift the parts.
The heavy-lift vehicle was sized to lift the largest single part, which was the turbine wheel, which was enormous, making the vehicle very expensive. But it turns out it was enormous only because the plant designer had gone for efficiency with no thought to the launch issue. By sacrificing 10% efficiency the turbine could be reduced to the size of the next largest part, which would enable a much smaller and cheaper rocket to do the job.
With the (unofficial) revised estimates, amortized over enough plants to feed the rate of growth of US power demand at the time, the total capital investment was a bit over a trillion bux. Sounds like a lot. But in fact it was cheaper than building any of the earthbound alternatives for the same capacity. (Fossil fuel and nuclear were both expensive - though nuclear wasn't yet politicized out of affordability - and the remaining options such as water, tidal, wind, biomass, etc. couldn't hack the demand.)
Of course that's without even considering that the fuel is free.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
You think that huge solar panels on the moon wouldn't be subject to these "missiles"?
Not only would they be subject to it, but going there to fix them is hella more expensive than repairing satellites.
The generators would then convert the energy into harmless microwave beams, which would be aimed at collecting stations on Earth
Apparently this dude has never put a marshmallow in his microwave oven.
You misunderstand the technology.
The household microwave oven uses K-band microwaves. These were chosen because they're strongly absorbed by water, resulting in very efficient heating of most foods. (There are several ranges of frequencies that do that. But K band is absorbed about the right amount to cook food through rather than frying the surface or mostly passing right through.) Microwave ovens also have a very high energy density because the microwaves bounce back-and-forth and build up until they're absorbed by the food (or the transmitter magnetron, which is why they burn out if you run them too long when empty).
The "microwaves" proposed for space solar power downlinks are MILIMETER waves - chosen because they're easy to handle and go RIGHT THROUGH water without being strongly absorbed. That's mostly so they'll go through humidity and clouds without major loss - though it helps that birds don't get cooked either.
At the downlink rectenna farm the milimeter wave energy density is similar to the energy density of sunlight to maybe three times that. But the rectenna is MUCH more efficient than a solar panel at turning it into electricity. And the rectenna intercepts very little light. You can graze cattle under it.
Even if there were an issue with the waves if they hit something ELSE (and for some stuff there is - it would heat up as if a heat lamp was shining on it), aim is not a problem. That's because the downliink is a synthetic-aperture system driven by a pilot beam from the rectenna site. The pilot signal is the only thing keeping the thousands of individual transmitters in phase. So if it's lost the beam defocusses. Most of it misses the planet entierly and the rest becomes nothing more than an annoying milimeter-band radio noise.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
An Anonymous Coward wrote:
"You also make this guy sound saner than he really is. He wants to mine materials on the moon for building a plant. [Well of course! cast a magic wand, change moon rocks into power plants!]"
Sending up machinery that can mine lunar soil (for the ores) and water (for fuel and oxygen) is far less expensive than shipping the constructed materials, even for extremely small projects. This would not be an extremely small project.
Give the moon a solar array and you can get a few watts. Give the moon a fab plant and it can make arrays for one heck of a long time. Better still, the gravity of the moon is 1/5th of that on Earth, so launching fabricated items to, say, Mars, becomes significantly less expensive.
It's certainly not trivial, but it is forward-looking. You can save a few bucks by launching parts to the moon, but economically, it scales worse than Napster. =P
My
Limekiller
The ONLY reason to use the moon is becuase it has cheap materials. Build your solar collectors (preferably solar lasers and whatnot) on the moon and lauch them towards mercury. The sun puts out more energy in a single week than has ever existed in ALL the reserves of wood, coal, gas, oil and nuclear fuel on the earth... combined. That is a frigging lot of free god damned power out there!
"Your superior intellect is no match for our puny weapons!"
Great - now all we need is a 385,000km cable to attach to it... oh and to shift the moon into a geo-stationary orbit so that the cable doesn't end up getting tangled - dang...
Funny you should mention this. Did you know you can get an approximate figure of the speed of light using only a common microwave oven, marshmallows and a ruler? Try this experiment:n 34/marshmal.htm
http://www.physics.umd.edu/ripe/icpe/newsletters/
This guy says it can be done for 135 billion. Thats alot of money, but lets just put this in perspective. Lets say the project goes over budget by say 20 percent (as alot of space programs tend to do) and ends up costing in the neighborhood of around 160bill. Damn thats alot of cash!
Then wrap your mind around this. Our government spent 60 billion to design and buy the latest and best fighter jet the F-22. Our military budget is $68 billion a year and expected to jump to $100 billion in the next four years. And you guys all think that this guy's idea is to expensive? If he has done the groundwork on the project enough to come up with a estimate, and ABC put up a story about it I would hope that we can at least believe his estimate.
$135 billion is chump change when you think about what would be accomplished. It could be a marvel of human genius. And perhaps it might make the world think a little better of us if we started producing all the power we actually used, while selling it cheap to them to.
He's worried about debris orbiting around the Earth, when his proposal involves potentially tearing up the moon's surface.
Still...the idea has some merit, just seems a bit crazy.
How shall I put this...?
Tornado? Cyclone? Hurricane? Hypercane? Willy-willy? Lightning? Sure, they don't hit a high enough balloon but they do hit the cables quite hard.
Also... doesn't that make things a little difficult for air traffic? How about shading if you've got that many balloons (or kites) up?
Got time? Spend some of it coding or testing
Bill could probably pay cash for it next week if he wanted to. And get a serious tax deduction. But he won't.
Got time? Spend some of it coding or testing
Seems to me it doesn't matter what they're doing up there, as long as they _are_ out there.
Where are the lunar-hotels we've been promissed? When will I be able to take a vacation on the moon?
I'm pretty sure that once we start building something up there, whatever is might be, we'll have to come up with new technologies, new ideas, etc.
When was the last time a man stepped on the moon? Space exploration nearly came to full stop in the past decade. All we do today is luanch more settalites -- can you say space junk -- and work on that ISS, which only hell knows when will become operational.
Sure, it's a stupid method of generating power, but if it involes going back to space, I'm all for it.
+5 Informative
The short way of saying `me too'.
Got time? Spend some of it coding or testing
A better idea that's technically not much less umptuous. Why leave it at the moon? We can build a huge spaceship travel to Alpha Centaury (our nearest star) and then build a sphere right around the star catching *all* it's light. Then send it as a "harmless "microwave to earth, and hope that earth doesn't just evaporate from all the energy.
--
Karma 50, and all I got was this lousy T-Shirt.
Dr. Evil may try to take it over, and ask for $1,000,000 - wait, $100,000,000, to prevent the barbecuing of NY State......
Do you expect me to talk?
Nooooo Mr. Bond, I expect you to die.....
It currently costs $10,000 to get 1 lb of material into orbit. How much would it take to get it to the moon? One hell of a lot.
You're right, but as others point out, the big project would rely on an in situ photovoltaic panel factory on the lunar surface instead of transporting the panels.
Nevertheless, I think it would be a good start to have a demonstration project, transporting and setting up earth-made panels on the moon just to see if we can beam some power back here.
At the very least, it would get people thinking about the project and its problems and get it in the public eye, which is essential to get funding in a representative democracy.
Just focussing people's minds on the problems is a good way to start solving them.
If we dismiss this idea out-of-hand as too expensive and impractical, it is pretty well doomed to remain too expensive and impractical.
"Provided by the management for your protection."
>if only God had made the moon tethered by two nice fat copper wires...
...
Don't you mean three? Notice all high voltage power lines are three phase and not 2 phase
TastesLikeHerringFlavoredChicken
It's just a matter of changing the mindset of business and government. And getting off the silly idea of power generation on the moon.
I'd have a personalized plate on my car, but "toxic bachelor" won't fit into 7 letters.
nor any drop to drink.
The same dilemma that faced the Ancient Mariner faces people who are looking for energy sources. It doesn't take much looking to find prodigious sources of energy that, for practical reasons, we cannot exploit, at least any time soon on the scale necessary to Solve All Humanity's Problems(TM).
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Should be pretty easy to fix. You would need to put something like a laser at the ground location firing at a receiver on the moon. If either drifted at all and this beam no longer hit the target on the moon, it would cease sending power. You could even play with modulation of the beam for security purposes.
.
load "linux",8,1
And WHY isn't every portion of the surface suitable for placing panels? Because it's pummeled by meteorites!
"I can't give you a brain, so I'll give you a diploma" - The Great Oz (blatently stolen sig)
First off, let's pretend we have the gobs and gobs of money needed to cover 1% of the moon's surface with solar panels. Then let's pretend that our increasingly fictional scheme will be in sunlight all during the month (as opposed to the two weeks when our solar panels will be facing the sun).
How exactly do you intend to get the power back here to earth?
There's only one reasonable solution: Microwave transfer. This means that this "environmentally friendly" energy you're getting will result in a very powerful microwave beam scorching a path along the earth's surface with the orbit of the moon. You'd be "saving the environment" by creating something that can (and will) cause death and destruction on the earth's surface comparable to a nuclear war.
Sorry, I think that building better fission reactors is a far easier, safer and cheaper way of doing things.
If it's a goof - frag'em.
(I know - we all mis-spell, but this is a Big Deal Scientist and this article made it past a science writer and an editor, eh?)
If it's a pun- frag'em then frag the fragments.
We'll give the author and the researcher the houses right next to the microwave receivers so they can then deal with the inherent problems in controlling a 240,000 mile long MASER beam when there's a 2+ second lag in your feedback loop for aiming those TERAwatts back to a constantly moving hand-off receiver network. (the moon may always show the same face to the earth, but it don't work the other way around - no spot on earth can see the moon all day - and for much of THAT time the geometry sucks)
OK - so go to a TDRS type satellite network - geostationary final leg - then tell me that it's more efficient to develop a microwave receiver farm from scratch (rectennas still only exist as science-fair-sized demos - this is like launching an estes Big Bertha then asking NASA to let you build the next gen shuttle...) than to just ramp up production on terrestrial PV cells?
The original PV geosynchronous satellite plan (Glaser et. al.,) is still too expensive to be implemented - and that would just be the final leg - imagine getting a manufacturing plant to the moon! We only put 16 tons of stuff on the moon six (ok we tried a 7th) times. And that was just to scott around for a weekend.
We're already getting upwards of a kilowatt-hour per square meter in most places on earth that need it - why not use what's here?
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
We don't have an energy shortage on Earth. We have a shortage of CHEAP energy. And, cheap is relative. No matter how cheap energy is, it will never be cheap enough unless it is free. So... We will ALWAYS have a shortage of CHEAP energy.
Today, right now, we ~could~ build solar energy collection systems that ~could~ provide pollution free energy, just not cheap. We could also dam rivers, and build windmills. Again, pollution free, but not cheap.
I don't think that solar panels on the moon can possibly be significantly more effecient than solar panels on the earth. And solar panels on Earth are not cheap! ( If they were, we would have more of them.. ) Search the web, you can buy them. They cost a lot for only a few watts when the sun shines.
How can a plan to spend $150 BILLION ( before it starts to break even.. ) Be a good idea?
$150 BILLION before it starts to break even means, that you have to invest $150 Billion up front, and then after a while you won't need to invest more because the system will be paying for it's self. How does the system pay for it's self you might ask, people have BUY the power from it...
Who PAYS BACK the $150 BILLION investment??? The people buying the power?? Citizens of Gov'ts. People of planet earth? Around 6 Billion people live on planet earth. So this plan would require each human, on average, to pay ~$30 American for funding. Easy for you and me.. Perhaps not so easy for Afgani's or Cubans who live on $100 / year, and don't even have electricity..
And even after way pay the world wide energy tax to fund the building of some quack's pipe dream, we still have to pay market rates for the power.... IT will NEVER, NEVER, EVER, ( don't even think it.. ) EVER be free. ( [ never ] )
The biggest part of my electricity rate goes to pay for distribution. Commodity electricity sells for 1 - 3 cents/kilowatt hour. Average price in USA to consumers is 7 - 8 cents/kilowatt hour. Even if a magical FREE ELECTRICY engine was invented, your rate would probably only go down 2 cents..
There is no such thing as a free lunch.
Kevin
...we forgot to account for the thrust generated by beaming all that power back to earth. We pushed the moon out of orbit, and sent the earth into an eccentric orbit eventually destined to rendevous with the sun. ;)
IANAAOEAAA (I am not an astronomer or even an ameteur astronomer)
--Lawrence Lessig for Congress!
Somehow nobody has yet linked to Criswell's original article, which was published in the current issue of the Industrial Physicist, put out by the American Institute of Physics, a highly respected research physics organization in the US.
:-)
In other words, Criswell is no crackpot; this is a realistic plan. Read the article. I don't entirely agree with him - I think lunar materials could more effectively be used to construct orbiting solar power satellites - launch from the lunar surface can be very cheap using electromagnetic railgun technology, and in orbit you can get sunlight 100% of the time, not 50% (with solar incidence angle effects to worry about too). But Criswell's scheme is one of the most promising options, and should be considered seriously.
How soon could this be done? Essentially all the technology is in place - the scheme could benefit from some further developments of robotics, but a first launch date of 2010 is not unrealistic, and we could have power from the Moon before we would see anything from ANWR
Energy: time to change the picture.
Look at the moon rising over Kandahar. It's only visible for a few hours at a time. That is not my definition of reliable power! Storing the energy or shipping it long distances introduces unacceptable losses.
> Begin quote
They would need to cover 1% of the lunar surface on BOTH sides of the moon, because only half of the solar panels would be in sunlight at a time.
They would need to cover 5% of the surface, because the cells are only 20% efficient.
Combine those two problems, and you have 10% of the surface of the moon covered in solar panels.
> End quote
No, you don't. You cover 5% of the total surface (or 3%, if a previous poster was correct, but we'll stick to 5 for now). That way, you'll always be covering 5% of the surface in the light. The 'both sides' of the moon argument is flawed, because you're always talking about the total energy received anyway. So, that's 10% of the total (or 6) rather than 20. It's still a monumental amount, but a lot less so.
I also don't see why an environmentalist should complain about being able to 'see' solar panels on the moon. Environmentalism isn't about preserving purely aesthetic matters, but about preserving natural resources. A lot of valuable, endagered habitats aren't all that attractive, but are still valuable. And I'm not sure it would be all that ugly anyway.
I'm not saying the suggestion is good, merely that your refutation is flawed, albeit based (apparently) on a very reasonable premise (excessive cost involved).
"What is freedom of expression? Without the freedom to offend, it ceases to exist." Salman Rushdie
50% of the moon is in shadow from the sun at any given time. That 50% is not the same 50% all the time.
During a new moon, the dark side is, as even you point out, the side facing us! It doesn't get sunlight, which is why we see black when we look at the new moon.
I guess the great slashdot blackout has only further reduced the signal-to-noise ratio in these posts.
I have been looking into PV systems for my home. At current RETAIL market prices, you can get a KW of 120 VAC generation capability for about $10K. This means that for $ 1M you can create 100 such systems. For $1B you get 100,000 such systems. For the 135 Billion this would be 13.5 Million systems. The benefits of doing it this way are 1. No distribution system required ( and no distribution loss ) 2. Distributed control of the resource ( big country can not hold little country hostage for power ) 3. Can be built incrementally as funds are available and if the project gets scrapped halfway through, what you have built so far is 100% functional and on-line. This model is very crude, it does not show the benefits of mass standardization of the systems and mass quantity purchasing. In fact, for a project of this size, the project could build or purchase a PV manufacturing plant and significantly reduce the cost of the panels.
Z
enough is too much
You are still thinking about this in a system where there is no atmosphere on earth. You forgot about refraction due to the atmosphere. The refraction might be small enough to ignore for the time being, but a large flux in the atmospheric pressure, storms, and you can have your beam focusing completely off target.
That's the point of the "pilot" signal from the ground. It experiences the same refraction, and its phase at the transmitter array controls the phase of the return signal. Even in the most violently mixed atmosphere the refractive index won't change enough to matter in the fraction of a second it takes for the return signal to arrive.
It's just like the holography hack where they record the phase distortion of the frosted glass and predistort an image so it is transmitted through the frosted glass and reconstructed correctly on the far side.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
If we replace our use of fossil fuel to generate energy with an equal amount of energy obtained from moon microwaves, there's no difference to the "current equilibrium". The point is that in the "closed system" that's really in question, both fossil fuels and external microwaves are external inputs. There's good evidence that our burning of fossil fuels *is* disturbing the equilibrium of the system. Replacing this with an equivalent amount of external microwaves would disturb it just as much.
A separate argument would be whether the abundance of clean energy from the moon would encourage greater energy use, but that's not the argument you were making.
135 billion really isn't that huge an amount of money when you consider, for example, what the US spends on cosmetics a year (something like 10-20 billion a year). So if woman just went without makeup for 10 years, we could have free unlimited power. Suffice to say over the long haul 135 billion is a drop in the bucket. The problem is getting someone to take responsiblity for the short term cost, but seeing as terms in office are 2-4 years it is probably too much to ask ;)
Since it's still way too expensive to even assemble and use geosync. PV satellites as described by Glaser et. al., then how could it ever be productive to launch something just as large to sit there and RELAY power coming from another more expsnsive installation 240,000 miles away? It's not.
Once upon a time we made ourrsleves believe that we could build lots of safe, effective, cheap nuclear power plants. In theory - yes. Practically - no. Why? Becasue when you look at things as a physicist, anything within the bounds of the laws of physics can be classified as a good idea. Hand it to an engineer, and you run up against a whole new set of limits that fall into the category of 'practical'. Then try to sell it to the public, and you have to address the realistic needs and wants of real people who you were supposed to be helping in the first place.
Please remember that our largest excursion series to the moon - Apollo - simply moved about 100 tons of equipment (16 tons six times) - and that was just to tool around for a few days each time. This power plan entails mining, smelting, metals purification, HIGH PRECISION manufacturing (you esssentially have to build a semiconductor factory to make PVs), etc... it's one thing to ask people to assemble fully debugged building blocks on Station, and if we can do that. why bother launching it to the moon?
And how you gonna get that much-ballyhooed railgun in place and working on the moon? They are another high precision, high maintenance piece of work. The Lunar Module Ascent Stage engines had exactly two working parts and a backup for each, and talk to the moon walkers about how much sweating they did over that simple little detail. I've seen a simple testbed railgun (firing mere bricks) go south, and would not want to be nearby in an EVA suit when it happens. There are far more practical details to doing this than the theory suggests.
I envision many large boxes marked "ACME" whenever people start spouting things like "get a railgun" , "go to the moon", "shoot stuff back". I spoke with Gerry O'Neill about these schemes several times when he was still with us - and while I admired him as a visionary, you still have to place all these use-the-moon schemes as Velikofsky in the 40s. Yes, it eventually worked. Yes, it was exciting. Is anyone going to the moon since for any practical reasons? No. Were there valuable spin-offs? Many. But no-one at NASA ever deluded themselves into thinking that the Apollo missions were worth billions of dollars as a geology field trip. And no one will go to the moon to build power stations simply because we need energy. We have energy. We need a better financial model and a better distribution network.
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
Ever have a cockroach get into your microwave and try to kill it by turning it on? They like it.
No area of the moon is "pummeled by meteorites" with a frequency worth mentioning. The moon is covered in craters for two reasons:
-When it was new, there are a heck of a lot more meteorites around. By now, most of the debris in the solar system has been "swept up" be planets. (Actually, the moon's new enough that this might not have a large effect.)
-No atmosphere = no erosion. Craters from ten million years ago are still in perfect shape.
NOW, I consider myself more of an armchair ecologist/generalist than an "environmentalist", but I have to kick up a fuss here.
On what grounds do you accuse "environmentalists", who are dedicated to preserving some sort of ecosystem in the face of our population and business growth, of wanting to protect the "environment" of the moon?
The moon doesn't have an ecosystem of which I am informed.
Preservationists, maybe, but not environmentalists. And Lunar Perservationism is not exactly up and running as a PAC. Hell, as an old O'Neill disciple, I'd rather the moon look like industrial New Jersey if it means getting cheap, eternal power for man. Besides, you'd have a really, really hard time picking out those collectors and transmitters with the naked eye. The moon has a pretty good albedo as it is. Shiny panels aren't going to raise it enough to detect without intruments, in my too-lazy-to-check opinion.
One "environmentalist" in the YES column, please. (Tho I'd much, much rather deploy powersats. Does no one read "The High Frontier" anymore?)
IANA Physicist, but seeing as photons have no mass, they would have no effect on any orbits or acceleration?
Yeah, all that wind up there is the pits.
t.
Sounds like reason enough to start testing a MDR (media death ray).
t.
t.
Mostly because the rectanna is just an overgrown TV antenna, with the individual elements sized smaller to use a higher frequency. It is called "rectanna" because they also build into it the rectifiers that turn AC microwaves into pulsating DC power. Make several of those into a square panel and -- bingo! -- you've got an element of the receiver grid. NASA's early tests had about 85% efficiency in turning microwaves to electricity. They could probably do better today.
Compare that to a silicon solar cell, which needs to have light penetrate into its blue-gray depths just far enough to generate an electron and hole pair in the active junction between the N and P layers. And, those electrons and holes have to be swept apart by the static field in the junction before they can recombine and be wasted. Designing a good solar cell is hard. It takes both quantum mechanics and serious material science, plus critical cost controls to be able to manufacture them cheap enough for widespread use.
"You've crossed my Line of Death!" "What? No! Where is it?" "Here in the fine print...."
Actually, that's a common misconception. Water's resonant frequency is several GHz higher than a microwave oven's 2.4 GHz. That was chosen as a good tradeoff between what was manufacturable back then and water's absorption spectrum.
Future power sats may use a different band, but maybe not. I once saw a frequency chart that had the 2.4 GHz slot marked "Power Broadcast". Wouldn't it be a kick if they used the same freq as ovens? It would make sense -- cheap magnetrons are readily available and the band is already cluttered with noise from leaky ovens.
It's also used for Bluetooth. I wonder if there would be any problems when the power sat switched on....
"You've crossed my Line of Death!" "What? No! Where is it?" "Here in the fine print...."
14 days out of 28 any part of the moon is in shadow. The energy From the Sun on Earth is immense compared to the moon. All you need to do is store enough of it long enough to eliminate weather as a factor. Positioning your collection array in the right place to begin with helps. Unfortunately even on Earth it's not economically viable now, going to the Moon and adding the complexity of beaming it back as microwaves is obviously not going to help that problem. Tidal forces and other schemes are also a huge potential energy source. There are vast resources on Earth at our disposal before we need to go off to the moon to beam back microwaves. Jeeze, can't NASA fire these nuts and spend our tax dollars researching useful stuff, instead of trying to contrive useless excuses to go to the Moon?
Or adding many more trees.
Tree's arn't really the best kind of plants for soaking up carbon dioxide. Because they are fairly slow growing and only a portion of the plant performs photosythesis.
A fast growing herbecious plant will do a better job.
Covering the moon with photovoltaic cells would make it a lot darker from the perspective of viewers situated on Earth. Not only would we lose an object of timeless beauty and inspiration, but many, many species of animals are thought to depend on the moon for navigation. If they can no longer migrate properly, this could mean interruptions in the food chain, in local ecologies, and worse. I hope someone stops to think about this before we go and blot out something so important and poorly understood as our nearest astronomical neighbor.
You see? You see? Your stupid minds! Stupid! Stupid!
The solution to that is to have the oscillator necessary to produce the microwave beam here on Earth, powered by a tap off the microwaves coming down. If the power transmitter doesn't get that signal, it can't make microwaves. And if the power beam wanders off the receiver, the power goes off on the transmitter that's sending that signal.
You have give the transmitter local power for startup, like that button you hold down on your water heater to bypass the safety valve on the pilot light until it heats up.
sorry. But is that 250 homes' power net, after you pay for running the digester and the manpower?
My God, it's Full of Source!
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