Science: Space Energy
Earth rotation as renewable energy source   (+3, -7)  [vote for, against]
It's just spinning around, let's harness that inertia

We can build a huge track all along the equator, with a car containing massive generators. Pull the car along the track with a long cable (perhaps using carbon nanotubes like the ones we're using for the elevator to space) attached to the south pole of the moon, with a swiveling connection to prevent twisting. As the moon's orbit pulls the car, it generates all kinds of electricity for the whole planet. And it's renewable for several million years (?), and environmentally friendly. Not cheap, but it will pay for itself eventually.
-- globaltourniquet, May 15 2001

Earth-Moon relationship http://earthview.sd...trees/moonhans.html
"...Back in the Paleozoic there used to be over 400 days per year" [hippo, May 15 2001, last modified Oct 21 2004]

"Wobble" theory of dinosaur extinction http://www.cnn.com/...r.wobble/index.html
Maybe we don't want to go messing with this stuff. [Dewey, May 15 2001, last modified Oct 21 2004]

The ultimate generator http://www.halfbake...ltimate_20generator
Kinda of the same principle, yours is more realistic though. [talen, Oct 04 2004]

Earth's energy from rotation http://mb-soft.com/public2/earthrot.html
C Johnson sees the same energy gold mine that you do. [Worldgineer, Oct 04 2004, last modified Oct 21 2004]

Uh.... only in a macrocosmic sense is it nonrenewable. The moon's orbit will eventually cease, so I suppose in that sense it's nonrenewable. But the time frame as compared to our lifespan sort of makes it virtually renewable.
-- globaltourniquet, May 15 2001


And before you attack me on the fact that it's the Earth's spin that's generating the electricity -- duhhh, you know what I mean. So I said it wrong. The moon in its orbit is acting as the anchor for the cable.
-- globaltourniquet, May 15 2001


You keep using that word. I do not think it means what you think it means.
-- bookworm, May 15 2001


Perhaps. Let's see.

renewable:
capable of being replaced by natural ecological cycles
(taken from www.m-w.com)

Energy used from this system, as I see it, would be replaced (renewed) by the natural ecological phenomenon of the Earth's rotation. Nonrenewable simply means the source of energy will eventually run out. What am I thinking wrong?
-- globaltourniquet, May 15 2001


This will have the effect of slowing down the moon, thereby lowering its orbit. Eventually it will run out of orbit and therefor stop providing power, at least in the form of electricity. But, the moon smashes into the earth at that point, erasing your power market. So it IS nonrenewable, but before it runs out no one will be in a position to care.

Actually, the more likely scenario is that the earth's will just slow to the point that it is locked in position with respect to the moon and you will stop getting power. Non-renewable. That's not the major problem with this idea, though.
-- centauri, May 15 2001


How do you know it will slow down the moon? By how much? Can we see the math? Doesn't it depend on how much force is applied? If the car is built to offer little resistance, we can minimize the slow-down to the thousands-of-centuries who-cares level. And anyway, won't it speed up the moon, if anything (that is, if the car resists the pulling to a significant enough degree)? The moon orbits the earth in the same direction as its rotation, so the car would pull it in the direction of its orbit. Then what would happen?
-- globaltourniquet, May 15 2001


The point is, it's not renewable. The energy has to come from somewhere. You're either decreasing the rotational kinetic energy of the earth, or the orbital kinetic energy of the moon, or, more likely, both. It may last for a long long time, but eventually it's going to go away or be nullified in some other way. Therefor, it's not renewable.
-- centauri, May 15 2001


The elliptical orbit is not a problem. the rotation of the earth is pulling the car, and the cable anchored to the moon is holding it back. It will hold it back no matter how far away it gets. As it pulls away from earth (approaches apogee), the car will just go faster along the equator track. As the moon approaches perigee, the car goes slower. but it still generates the power.

The weight of the cable: can't we make it light enough not to pull on the moon (any worse than gravity is already doing)? I mean, the earth surely exerts more pull on the moon than our puny little cable.

Anchoring to both planets: What, you think it might pop out of its socket? If we can't engineer a tough enough clamp, then the idea dies. But the car will not resist the pull of the cable at all, so any force will result in the movement of the car along the track, not the yanking of the cable out of the socket. Unless something interferes with the car's motion. But we can take steps to prevent that condition. A massive cow-catcher.

And centauri, by your definition, there's no such thing as renewable energy. But that's what they call solar power, wind power, and the like. Surely the sun will eventually explode. So it isn't renewable. But on the scale of humanity, it, like the rotation of the Earth, is renewable. This isn't a flight on the face of the first law of thermodynamics anymore than the appellation of solar power as "renewable" is. If you notice, in the original post, I said "renewable for several million years" (or however long the Earth will be rotating with a moon orbiting around it).
-- globaltourniquet, May 15 2001, last modified May 16 2001


No, no, not at all.

The Sun will burn out eventually, it is true, but using solar power will not make the Sun burn out any sooner: renewable. However, using oil from the ground *will* cause our oil resources to be depleted faster: nonrenewable. Extracting energy from the Moon's orbit *will* cause the orbit to decay faster: nonrenewable.

There, now that we've settled that... *cough*

Tidal power is, of course, a very small-scale version of this; the Moon pulls on the oceans through the "tether" of gravity, and we can extract energy from the sloshing.
-- egnor, May 16 2001


Even if you could overcome all the above mentioned obstacles, and somehow get the car to glide along the track smoothly enough that it wouldn't degrade any orbits or rotations too quickly, once you set up a mechanism to convert that motion into electricity (the generators you mention) you immediately create resistance to the car's otherwise free movement, don't you? And then you're back to degrading orbits etc.
-- PotatoStew, May 16 2001


I seem to recall that the moons orbital radius is already decaying at the rate of something like 6 feet a year, from tidal drag, so you'd need some kind of mechanism to real in the slack on the cable.
-- gravelpit, May 16 2001


Actually, gravel pit, the moon is receding from the earth at a rate of a few centimeters a year, due the the fact that the earth has a bulge on one side. This pulls on the moon as the earth rotates and simultaneously speeds up the moon (increasing its orbital distance) and slows down the earth (lengthening its day).
-- centauri, May 16 2001


The moon is already slowing down the earth's rotation (and so making the day longer) - tidal friction. See link.
-- hippo, May 16 2001


You could fund this fairly large operation by running trips to the moon up and down the cable. People pay millions for trips into space.
-- gardnose, May 16 2001


I think we should just tie a giant string around the moon and do yoyo tricks.
-- thumbwax, May 16 2001


I can do yo-yo tricks, but since when are _you_ lunartourniquet?
-- globaltourniquet, May 16 2001


Let's not forget to attach boxcars and passenger cars to the car on the track. It might have limited use as a form of transportation, but it would be in effect free and non-polluting. And I assume the schedule would be difficult to memorize.

We'll also clamp some cameras halfway up the cable for the Weather Channel. We'll attach a pump that will suck ozone out of the lower atmosphere and channel it into the upper atmosphere. And if an asteroid ever threatens the Earth, we'll attach powerful engines to the generator car and use it to swing the Moon around like a mace and whack the asteroid out of the park.
-- ejs, May 16 2001


Many natural phenomena are powered at least in part by the earth's rotation; tides are the most significant example. While some of the energy from tides is taken from the moon's orbital kinetic energy, most of the energy comes from the earth's rotational kinetic energy.
-- supercat, May 16 2001


I was wondering if the cable would be 'attached' to the Moon like a tetherball.
-- thumbwax, May 17 2001


Yes, that one is called "Around The World" not to be confused with "Shoot For The Moon" or "Ursa Major" or "Ursa Minor" or "Gemini Loops" or "Tidal Wave" or "Flying Saucer" or "Warp Drive" or "Sky Rocket" or "Orbit Launch" or "Planet Hop" or "Astro Loops" (outside) or "Lunar Loops" (inside) or "Gravity Pull" or "Rock The Baby On The Launch Pad". I knew this Yo - Yo book would come in handy someday.
-- thumbwax, May 17 2001


And exactly whose backyard is this track going to be built through?(the bits that are on land that is. Building a track across the oceanic parts is going to be interesting).
-- DrBob, May 17 2001


Minor problems we can find solutions for.
A remote release of cable from moon can be used for maintenance or to prevent giant tetherball effect if necessary. Jets at moon end of cable keeps it suspended in space during maintenance to prevent it from whipping around the planet (causing quite a sting). Brake system stops the car (eventually). When we are ready to resume rotation energy generation, astronauts retrieve cable and reattach to moon. Simple.

As for whose yard, come on. It's the equator. Who along the equator really has any say, after all? Well, a couple of oil-producing nations who would go out of business because of our plan, but they have no military influence without our protection, right?....

And now for the ocean. Of course, just build the supports all the way down. We've done harder things (without, I might add, the help of ancient astronauts). Look at the pyramids. OK we can't use slave labor, but it could be done.
-- globaltourniquet, May 17 2001


HAHAHAHAHA
g-lo: come on-tell the truth... Is that tongue of yours wedged in cheek?
-- thumbwax, May 17 2001


I enjoy a forum where (on-the-surface) outlandish ideas are seriously discussed, because in my experience in the business environment, it is healthy and mind-bending (thinking-outside-the-box, if you will), and the greatest innovations that are "inlandish" often spring from such discussion. It is important when formulating arguments for outlandish ideas to be close to precise pragmatically, but not THAT important. I have been in brainstorming meetings where the stupidest comments, because they were not discouraged by the wise moderator, have led to flashes of unstupid inspiration in another brain present.

For instance, thought about this uncontrollably spinning earth being a source of energy could lead to real, practical ways to harness it. Tides are an obvious example and even available, but so far of course they are only good for those areas that happen to be near them. By talking about this idea, it would be interesting to see if anyone could imagine an even partially or perhaps nearly (technology-wise) bakable concept that is similar. Like doing something similar with particle beams of some sort (I'm just brain farting there of course, but you get the idea). As a matter of fact, this is part of what the half-bakery seems to me to be about.

So tether the moon and speed the little car around and generate some serious power. And if we can't do that, well let's think of something else.
-- globaltourniquet, May 17 2001


I didn't think the moon's orbit was coplanar with the equator, at least not always. Furthermore, I think the north-south angle relative to the eqautor varies. I know the sun does this (or we do it relative to the sun. Whatever). And you should change the title to "moon's rotation..." As for the problem of the earth's rotation slowing, I could really use a longer day. As for the moon crashing into the earth, Zelda 2, anyone?
Off-topic (sort of), using the earth's rotation by looping a really, really long wire around it several times would be interesting. But then there's the problems of how to make it spin, keep it spinning, and eddy currents which would not only slow, but also re-orient the earth's rotation.
-- nick_n_uit, May 18 2001


The rotation of the moon is completely immaterial. The anchor on the moon is on its south pole, and the fastener swivels so as to ignore the rotation of the moon. The Earth rotates, pulling the car in the track in the rotation-direction (counter-clockwise) away from the moon. At cable tension, the car begins to be pulled by the cable, anchored to the moon, in a westerly direction relative to you standing in Ecuador watching it whizz by. So the energy is generated by the rotation of the Earth.

The moon's ORBIT is indeed not coplanar with the Earth's equator. But if the cable is long enough, that doesn't matter. It just goes north and south of the equator as the moon does. It will still pull the car.
-- globaltourniquet, May 18 2001


Well Gee Whiz. If every single idea here was so fortunate as to have things such as reality be immaterial, there would be no need for fishbones- which apparently you're trying to corner the market on.
-- thumbwax, May 18 2001


Wriggle out? Certainly not. I was just clarifying the intent of the idea for nick_n with that last one. He clearly misunderstood my fantasy....

And thumbwax, when I said the rotation of the moon is immaterial, what I mean is it isn't germain to the discussion. It plays no part in the physics of the mechanism, due to two things: The swiveling connector, and the fact that the moon always faces the earth anyway, so we could even anchor the cable to the most optimal place on the face of the moon, if the swiveling connector on the south pole didn't work. I'm not calling reality immaterial. I'm dismissing the moon's rotation as a non-factor. Geez.
-- globaltourniquet, May 18 2001


The moon 'faces' the earth.
-- thumbwax, May 18 2001


Yes, good, you can read... that's what I said... (and it does, in a manner of speaking)
-- globaltourniquet, May 18 2001


Having downloaded .jpgs, made well over 100 .gifs and ani- .gifs of the moon far prior to this date has given me sufficient time to falsely believe that which I have observed with the naked eye, binoculars, telescopes - including Griffith Park Observatory which is scant minutes away from my residence has no relevance to the earth and hey-wow the moons rotation and orbit.
-- thumbwax, May 18 2001


It's OK. You clearly don't understand. Nevermind.
-- globaltourniquet, May 18 2001


<childpsychology>Yes_you're_right</childpsychology>
-- thumbwax, May 18 2001


Hey g. lo, how about this?

Buckminster Fuller, halfbaker extraordinaire, said that you could build a geodesic dome around the whole Earth and it would be self-supporting. Let's build two concentric geodesic spheres around both the Earth and the Moon and tether the outside spheres together. This will be, in effect, frictionless universal bearings around both bodies. The moon could go every which way around the earth and the geodesic spheres will just rotate in place to follow it. Electrical current will be generated from the movement of the outer spheres across the inner spheres as the Moon orbits the Earth. No building on land required, no track-jams or tetherball effects either, and we can build space elevators up to the inner sphere. Voila!
-- ejs, May 22 2001


Oh, ejs, they (read: thumbwax et al) will just say it would cost too much and then go turn on all their appliances. Except for UB who doesn't use electricity except to power his smoothie blender.
-- globaltourniquet, May 22 2001


Well, I'm probably a little bit late to join the discussion, but it sounds really interesting. I think that a big problem would be the force exerted on the tether. Assuming you want to generate an extremely large amount of energy from this, there is going to be an extremely large amount of back EMFproduced by the rotation of the generators, thus making it extremely difficult to get the turbines spinning to make the electricity. This force would most likely be far more significant than friction on the car (which could be minimized by making the track Mag-Lev).
-- MuddDog, Jul 03 2001


Hey UnaBubba, whip up a batch of smoothies and send some to me and (how was your vacation?) globetrotter via Space Cable.
-- thumbwax, Jul 07 2001


It is impossible I'm sorry if i broke your dreams
-- BALIKEKMEK, Jul 07 2001


Just put some giant coils around the earth's equator, fire some rockets so it starts rotating end-over-end, and let the earth's magnetic field give you the largest generator in existance!
-- octal, Jul 19 2001


Isn't geothermal energy just an indirect way of using the earth's rotation as a power source?
-- baf, Jul 19 2001


Several problems. First, I think I recall that the speed of the car is moving somewhere around 1000 mph or something. that means the cable is moving at the same speed. if you also remember that astronauts reentering the atmosphere really worry about a little thing we call friction. The space shuttle, in a synchronos-orbit, must travel about 17,500 mph (for reference, it goes approximately the same speed as my "super-shoes" do in December when the weather is right). In order for them to reenter the earths atmosphere without turning themselves into a spacedude-burger, the must decellerate about 300mph per SECOND by making a really LONG gradual arc towards the landing spot. Meanwhile, the space shuttle generates enough heat to deep fry Texas EXTRA CRISPY. yum. They even have a layer of porcelain that absorbs some energy, which after a certain point, melts and goes off into the atmosphere. Now the only thing that saves them is TIME. They are only in the space shuttle for a few minutes, before they land. Follow me so far? K, now that we are on genious levels, we now take a goood, looooooong look at yonder cable. hmmmm. Time is the answer. Or the problem (it depends on your perspective). Since yon cable neither is decellerating, nor enough procelain to save it, it will have a fate similar to most Kentucky Fried Chickens, except it will be vaporized before my niece can prounounce the word "oops". Oh yeah, one other problem. Say that cable lasts long enough through the atmospheric reincarnation of hell you have created to last a few centuries into the future. Asumming no energy is lost, the amount of energy is considered constant, thus a finite amount of energy is produced. The hitch in your giddyup is that while the energy stays constant, the rate of human growth does not. In fact it increases exponentially, which means that if 1000 people lived in NYC in 1700, and about 1,000,000 people live there present day (give or take a million), then about 1000 times as many people will be using their now super-ultra-premium suckage dustbusters in the said future. In other words, the rate that we use energy today will increase 100 fold times that in the future; therefore, more energy (potential that is) will be needed to supply the growing population at hand. In short, the idea is that you need a gadget that will not only supply us with energy, but will increase production when the population increases. That means, my dear Watson, that nothing has been gained, thus your creation rendered "fubar-but oh so amusing".
-- FloatLikeRoc, Jan 07 2003


sp: foucault
-- rowlycat, Jan 08 2003


It is the Conservation of Energy Law, "Energy cannot be created nor destroyed."

It is fact that if this were to be in place that it would put resistance on both the Earth and the Moon, slowing it to a stop. Then one side of the earth would be "halfbaked" because it could alter the seasons, and possibly slow the flowing iron in the core, depleting the magnetic field of the earth, similar to mars. There are better uses for the moon. Also, the money used to create the device could supply more viable energy sources, such as nuclear fusion.

Perpetual Motion is impossible and this is no exception. I see your logic, but it is useless to defend the idea. I hate how there is always that one thing that can spoil an almost perfect scenario.
-- empty89, Nov 26 2003


Don't know how I haven't noticed this gem. I thought I'd do the math on how much energy you could pull from the earth's rotation without effecting things, but it looks like someone's done the work for me. Turns out you could power the US for 1.4 million years using this scheme (assuming perfect efficiency - my guess is more like only 500,000 years) while only slowing down our year by a second. See link.

Of course, I was assuming earth's rotation would be the limiting factor. The other possible limiting factor would be accelerating the moon to the point that it leaves earth orbit. The math is similar for that scenario, but it looks like I've run out of time for today.
-- Worldgineer, Nov 26 2003


Would one's power increase and decrease as the trolley wizzes past your longitude? I'm sure the manufacturers of UPSs for computers would be over the moon ... no pun really intended, but once I said it to myself I couldn't resist typing it.

Certainly the idea doesn't fit the "renewable source" definition so I agree with those here who challenge that aspect. I found this discussion by accident as I was looking for info on the retardation of the earth so I could write a more accurate easter function for church spreadsheets. If this plan goes ahead I'll never get the spreadsheet done with people changing the figures even further.

I was amazed by some of the stuff I came across - people concerned that the earth was slowing down because more people were being born and therefore more office blocks etc. I don't know where they thought the matter was coming from to make these "new" people; that gave me a giggle.

I did start to wonder about the increasing mass of the planet though (not through people being born of course, but from the mass of iron we annually accumulate from meteorites. That does raise a point which is more relevant to this discussion than anything else I've typed so far, and that is - put a really big magnet in orbit so that all the meteorites approaching earth land on us from the same direction as rotation and add a little momentum each day to pick up speed. Then we might have that renewable source of energy first mentioned. Of course more people will have to go on diets thinking they'd gained weight when really it was just a slow increase in the planet's gravity, but of course that answers the other daft question raised about all the extra people on the planet. More bodies, but each one just a bit thinner than the last.
-- macchusswell, Dec 21 2003


some, but at least most can type. [clintoncole55]
-- jonthegeologist, Feb 12 2004


First of all this "big" cable you are making would have to be able to handle the heat of the atmosphere. Remember the moon is moving really fast and the air resistance may generate a lot of heat. I am not sure on the distance of the earth to the moon and the speed of the moons orbit so i cannot be 100% sure on this. If the moons orbit is too slow and since it is at the end of a big circle the center would move too slow to move this cart. But i like the way you are thinking and i give it a plus, just it would be extremley difficult to do. Other strange things may happen as well, such as the wire would always snap because of the preasure of gravity pulling on it at the same time. The gravity of the earth and the moon would play tug of war with it and would make it break at the center.
-- JoeLounsbury, Feb 13 2004


With the money that all this would take to research and build and everything (and all the trips to say, Mars, that we would need to take to get the extra matter we would need to build this super long cable, which would have to really be a more of a tower...it would need to be like 20 miles thick) I think would could build a much more efficient device to obtain energy. Assume, that is, that we could some how find some use for all this energy. Its not like there is a big energy problem...sure we have problems transporting energy (thus the need for gasoline...a good fuel cell hasn't really been developed) but who out there has a flux capacitor that need 1.21 jigawats of power. Anyways, assuming we somehow had enough super dooms day lasers that we wanted to shoot at enemy star systems (which would could see, seeing as we would just have a telescope that's hooked up to a big old delorian with all the time travel stuff from Back to the Future), assuming that, I think there are much better solutions. For example, why don't we just mine up Mars and turn it into a giant death star kind of thing. We'd outfit it entirely with solar panels, and produce more then enough energy to power whatever we somehow have to power. It doesn't have to even be on such a large scale, just mine up some asteroid or something and use all the matter to make a 50 mile long solar panel array. And people are all worried about that kind of thing blocking out the sun for some reason. Who says its in front of earth. Fly the stinkin thing far from earth where it won't bug us. Then run space ships full of some kind of fusion power cell thingy back and forth to get the energy. You may say, "but then your wasting a bunch of energy moving the actual energy" but no one has even mentioned how we are going to obtain the energy from the mach 1.5 little equador car (which by the way, could be like a plane or something and thus wouldn't even need a track. In fact, it doesn't even have to be on earth. Just put it in the exact center of the moon and Earth's gravities; like the point where Earth's gravitational influence is the same as the moon's. You put a big ol' counter weight kind thing out there and jump start it with some rockets. As the Moon orbits around the Earth, the Earth pulls the weight, and keeps it tight. That solves most of the problems right there....what a long parenthesis....) so ya, how are you gonna get the energy from the super fast car? Are you hooking a wire up to that thing??? It'll just get ripped out of the ground. If you had it on a winch thingy, it would slow down the thing quite a bit, and even if it didn't, it would wrap around earth forever and ever. I would actually use a laser I think...mount a laser on top of the car, and have it fire at whatever you need power to. It could bounce of satellites and down to cities or whatever. At the city, you'd have a big receive thing that would charge up and boil water or something. And assuming that everything I've said is crap, why do you have to do it with Earth? Everyone is worried about slamming the moon into Earth or something... so why not just do it with Mars and Phobos or something? You could have it shoot a laser at a satellite around Earth and thus easily get the energy over to our planet. And then if the line breaks or something and Phobos gets winged into Mars crushes all the poor defenseless Martians, if that happens then who cares? What have Martians done for us anyways??? This discussion started like more then 3 years ago tho (primitive fools, we acctually HAVE a magic moon gravity generator in 2004…although I’m not sure how your reading this 3 years before I wrote it….) so I’m sure no one will read it and I’m sure that everyone who posted something has long since figured out the problem with their argument. Thanks for reading!

-Andy (mradamantium@hotmail.com)
-- Hoju, Jun 10 2004


Hmm...[andy] i need some good amount of time to understand your views. anyways, must say - good effort (till i understand).
-- vedarshi, Jun 10 2004


[hoju] suspect what you've posted is very worthy, but is very difficult to read. Please see the help file for details of adding line breaks into your annotations - put the letters BR in between a "<" and a ">".
-- jonthegeologist, Jun 10 2004


The energy would be transmitted via the train track rails.

And this has been pointed out before, but I wanted to repeat it. This activity would actually speed up the moon's orbit.
-- GenYus, Jun 10 2004


Tether Ball anyone?

Actually, the hydroelectric systems that harness the tides today better utilize the moon's potential.
-- BMCCUE, Oct 10 2005



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