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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?
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.
...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"?
Do you know how many wind/solar power system exist, and are relied upon to provide power 24x7?
Tons. They use battery's, it stores energy for times when there is a "cloudy day". And as for the jets we could develop system of side thrusters that move it out of harms way. We can use GPS to triangulate the position of the planes and the exact amount of thrust required. This could be handled automatically by a computer........ that was a joke.
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
The moon also has no atmosphere in which small high-velocity space travelling rocks burn up. Last time I checked, solar cells weren't bullet proof.
> 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."
True, but you could trim down the number of solar cells needed by at least half if you put orbital solar collectors at Lagrange points 4 and 5. Those two are stable so they'd require no (little) position keeping fuel or thrusters and they'd be in full sunlight all of the time. The same concepts of microwaving the energy would still apply. Probably more effecient to "beam" the power to a substation in Geosync orbit and then have it been a concentrated microwave signal to a specific point on the planet.
On the efficiency side, you don't necessarily need photovoltaic cells. Some of the solar plants on earth use mirrors to heat water which then turns a turbine. Something similar could be used in space.
Planetes
"One World, One Web, One Program" - Microsoft Promo Ad
"Ein Volk, Ein Reich, Ein Fuhrer" - Adolf Hitl
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.
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load "linux",8,1
I'm looking at an article right now from 1999 that gives 32.3% efficency. Lets say 33% becuase I'm lazy.
At 33% you only need to cover 3% of the surface. To get both sides you need a total of 6%.
I don't see why you have to add 5% because not every portion of the surface is suitable for placing panels. That won't take up more area, just more work.
So lets say, by the time we actually have the resources to do this sort of thing, the improvements in solar cell tech have improved to cancel out the transmission losses. Ta da, 6%.
Sheesh. Pessimist.
Democrats or Republicans. They are both taking us to the same place and they are not afraid of us anymore.
Actually it wouldn't be a bright shiny ring, it would be a dark ring. Shiny would indicate that the energy is being reflected out into space, when in reality is is being absorbed.
The affect would be to make the moon look like it had been cut in two.
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
> 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