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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."
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.
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.
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.
Total nonsense?
Sure, you could pursue fusion.
But we may not get fusion. Should we wait
for the PERFECT energy source while we rely on
the bad ones, unstead of using a better one,
while we pursue the goal of fusion, which
(while theortically realizeable) doesn't even
have a timetable associated w/ it?
Furthermore, sure, the short-term costs would be
large, but what are the costs for building and planning a new nuclear reactor?
Solar cells on earth? We have clouds. We have day and night. The moon (thanks to an astronomical quirk) has permanent day and night. Much better
efficiency that we can get. Store it there.
Send it over, microwave style, when the terran
receiver is in place.
Or bounce it off a satellite.
Just because you can conceive of better long term ideas, why should we not pursue a better short term idea, rather than stick to one that's actually harming us?
-Slackergod
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
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
Given that most of the world looks with horror on the 'fact' the US consumes ca. 30% of the world's fossil fuels, it would be great PR!
Better to be despised for too anxious apprehensions, than ruined by too confident a security. --Edmund Burke
> adding additional energy to what is effectively a closed system. In other words, at least burning fossil fuels is harnassing energy already collected and stored by Earth.
The Earth is _not_ a closed system. The global temperature depends on an equilibrium between input energy and radiated energy. That's why greenhouse gases can raise the temperature. And the main concern with fossil fuels and global warming is CO2 being a greenhouse gas, not the actual heat dumped into the atmosphere by exhausts, cooling towers, etc..
Burning fossil fuels releases energy stored hundreds of millions of years ago. There have been massive climate changes since then, and the fact that energy was once sunlight hitting the earth is completely irrelevent to the current balance.
rant
Like I said, it is effectively a closed system.
The amount of energy radiated from the Earth is part of the system. Adding extra energy that is normally received by the Moon adds energy to the system that would not normally be there.
My point is that the Earth, as an effectivley closed system, has feedback systems that regulate the temperature. Yes, greenhouse gasses prevent the release of energy. However, historical sea level records (and other proxies for global temperatures) show that temperature fluctuations increase wildly immediately before ice ages. In fact, global temperatures increase several few degrees in a geologically short period of time (less than 1000 years) immediately before each ice age. This is one scientific argument behind people that claim we are not moving the Earth out of equilibrium (yes, some scientists are able to provide supporting evidence that we may be entering an ice age).
Adding any external input to an effectively closed system *does* have an effect on the current equilibrium. My question isn't whether it has an effect (it does), but rather how great the effect is. The amount of greenhouse gasses we are currently releasing is trivial compared to the gasses released during enormous volcanic eruptions. That doesn't mean we should wantonly release greenhouse gasses. Instead, we should view our acts as external inputs that may affect the equilibrium (by contrast, volcanic eruptions are a part of the system). My question is, "What effects would occur if we consumed all our energy from a source that is external to the system?" This will undoubtably have an effect. The effect may be insignificant compared to the amount of energy released from the Earth's core due to radioactive decay. I don't know.
If you have any evidence (supporting or contradicting), please let me know. But please don't give me pedantic definitions of a closed system that are irrelevant to the question at hand.
--Be human.
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."
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
> The amount of energy radiated from the Earth is part of the system.
Oh well in that case the answer is simple.
Redefine your "effectively closed" system to include the Moon as well. Now transferring energy from the earth to the moon doesn't add anything to the system, just moves it about, so you don't have anything do worry about.
> My point is that the Earth, as an effectivley closed system
This isn't pedantry, you're just flat _wrong_. It's like saying "Microsoft Windows, as an effectively Open Source project".
> Instead, we should view our acts as external inputs
So last post fossil fuels were part of the system because they were formed on Earth, but now they are an external input?
rant