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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."
But c'mon. The moon's surface area is something like 38,000,000 km^2. So harnessing 1% of all that solar energy would entail 100% efficient solar panels over what? 380,000 km^2?
Get back to me when you've got the first hundred square kilometers or so done...
Christopher
Mozilla
Ah, but imagine the new global economic return just in the number of jobs this would create.
Rememeber that this would be akin to colonizing the moon and not just for curiosity's sake or 'research'. We've been looking for a viable commercial reason to do something like this and voila!
Do you realize how much this would further the US's interest in developing countries... if we didn't have to build their power grid from scratch, we could hire all those work hungry people out there to do everything we don't want to do and for pennies on the dollar!
I do care about people though and of course I'm thinking about the children and what a boon for them to have 24/7 access to teletubbies which would free up their mothers to join their husbands in the manufacturing plants.. all powered by the lunar energy consortium (or whatever) at very low rates, because when you have the whole world as your customer base you don't need to charge much individually. Better yet the energy could be bought nationally and redistributed by local carriers who could compete for customers, etc... sounds good to me.
A fool throws a stone into a well and a thousand sages can not remove it.
Yeah, so uh what's so special about the moon exactly?
:)
Yeah, strange why there is no life on the moon, isn't it? We have this cool thing (well, for a while, anyway) called an atmosphere. It kind of cuts down on the whole solar radiation thing so we don't, um, die.
great idea - so how will the power get to earth? how about a cable....
I first heard about this wacky idea of transmitting electricity via electromagnetic waves a couple years ago, and apparently some other people besides this guy think it's a viable solution as well. I don't remember enough from my physics classes to say authoritatively whether these ideas are feasible or not, but it's a damn cool idea nonetheless.
The orbiting satellites would obviously be much cheaper than moon stations, and could be positioned above a specific point on the globe. This eliminates the need for "global cooperation", since whoever puts the satellites up in orbit would put them above themselves, thus receiving the free energy. The Moon generator idea would require receiving stations all over the planet, and if any one of them failed for any reason, the whole planet would be without power for a few hours. Also the Moon station deal is basically an all or nothing project; you can't be relying on your power source to be unavailable for 12 hours of every day just because you can't run enough cables around the planet to your country. The satellites could be put up one at a time as funds allowed, at a cost of about a half billion $ each, as opposed to the $150billion estimated for the moon project. So obviously the satellite approach is much more likely to be feasible than the moon version. But I still like to see other suggestions in the media as to energy sources other than "we must open up ANWR for drilling"... no matter how wacky they may seem to be today.
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.
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
Yes the earth recieves much more then the moon, but...
All very good points, but the costs of getting all the building materials to the moon, having people on the moon to run it, and then getting the power back down to the earth would make lunar power well nigh impossible.
I think solar power is going to grow, but I don't forsee it as being huge solar farms in Arizona, or anywhere else. I see it as being much smaller units that people use to help lower their home's dependency on fossile fules and the electric company.
Last I heard, solar power wasn't very affordable or efficient, but was getting better. I don't think it would take very much, relativly speaking, to develop solar power that is attracive enough for widespread home use, at least in areas that are rich in sunlight. People stuck in less clement areas will probably move towards things like hydro-electric power, wind power, etc.
Actually, hydroelectric is probably more realistic than any other alternative power source. It is already in use in some places, and is proven to be effective. You don't need the large surface areas of solar or wind power, and distribution works just like any other electrical transmission. The only hinderence is lack of waterfalls or powerful rivers.
It's also important to point out that these thigns are not going to replace fossile fules, merely augment them, at least for the time being. There is too much investment and inertia in fossile fules to change overnight.
The earth is full of resources that we can use and replenish; all it takes is enough public interest to get the government involoved or, more likely, give private business reason to start developing those areas. Environmental benifits aside, this would also lower our dependency on the OPEC countries who's distant cousins we are currently waging war on.
Thomas Galvin
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!"
I've thought about this before. Unfortunately, there's too much weather around. We want to make these things as cheap as possible, and so that they last. I think the basic plan was to put two hydro dams between England and Ireland - really quite short distances in the end. Alternatively, France and England. This leaves you with several hundred square miles of relatively calm, flat sea water.
Sea salt is corrosive too. (In the sense that it catalyses rusting and most other oxidation reactions).
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.
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.
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."
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."