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Wave/Sea Power - What Are the Dangers?
worldwide_ants writes: "My main worry about power generation from waves, is that we would put the earth in danger by accellerating the descent of the moon into the earth, since the moon would have to expend more energy in generating tides, and thus lose it's kinetic energy.
How serious a problem is this? What are the solutions?
Could we send a rocket up to give the moon a 'kick' once in a while?" This reminds me of an Isaac Asimov novel I once read ...
Speaking of Australians, our toilets up here in fat ass North America flush clockwise. So, in what direction does fat ass Southern hemisphere toilets flush?
Don't tell me they flush them clockwise too, that imbalance would make this world go down under quicker than I thought.
Oh, there was rioting by advocates this archived article reports.
Whoever's at the controls of /. today: Take the hint & cut the crap. It's not clever, it's not interesting, it's not not worth a damn. If you honestly can't find anything that belongs under the "News for Nerds. Stuff that matters" banner then just go silent.
Posting stupid article after stupid article is NOT getting you folks any favor-points.
What if /. were hijacked by script-kiddies? Could we tell today?
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
The oil won't lubricate the earth-water interface because the oil will spread out on top of the water into a thin enough film that it'll float instead of sinking down to the ocean floor.
I see even classic Slashdot is now pretty much unusable on dial up anymore.
Just wanted to applaud the subtlety of your wit, anticipating that not only would Slashdot make the mistake of saying "different than" instead of "different from", but that they would also make the mistake of using "then" rather than "than".
I see even classic Slashdot is now pretty much unusable on dial up anymore.
Recognizing that someone else didn't get a joke is not the same as not getting it yourself.
As far as social situations are concerned I'm sure I handle them as least as well as someone so easily provoked as you seem to be to an entirely disproportionate amount of anger over trivial matters .
I see even classic Slashdot is now pretty much unusable on dial up anymore.
Oh man, that 2 directions bit almost made me squirt coffee out of my nose. heheheh
Interestingly, we have slowed the rate of decrease of the earth's rotation measurably from hydropower. Hydropower dams are typically at reasonably high latitudes, and a lot of water has been stored there; closer to the axis of the earth than it would have been otherwise. Some calculations show that we'd have had dozens of more leap-seconds had this not been happening.
Global warming, though, will throw this all for a serious loop. If the icecaps continue to shrink and the sea level rises a few to ten meters; truly massive amounts of water will move further from the axis, slowing the earth by many seconds/year. I have no idea what the effect of this might be.
thad
I love Mondays. On a Monday, anything is possible.
While I don't agree with the assertion that there would be a problem with using the tides to generate power, it is known that the tidal bulge on the oceans actually leads the moon and the gravitational effect of this bulge actually is pushing the moon away from us... Since they're talking about harnessing the tides at the shore line, one can imagine that the effect of harnessing that power on the orbit of the moon will be negligible.
Surfing the net and other cliches...
Surfing the net and other cliches...
(Who Meta-Meta-Moderates the Meta-Moderators?)
Either you're pulling a lame April fool's or you don't know physics. Either way dude...
MSBPodcast.com The opinions expressed here are my own. If you don't like 'em... Think up your own stuff.
Expend it's energy? Gravity does NOT get expended. The moon's gravity causes the tides, not its inertia.
Thank God April 1st is almost over this is getting pretty fucking annoying.
LK
"Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano
California's plate is moving North, not down jackhole.
I'm a loner Dottie, a Rebel.
...is that when you are GMT-10 (or whatever we are in Melbourne now that daylight savings have finally finished), all of the slashdot April fools jokes are posted on April 2nd. When none of them are even remotely funny, you just end up confused. I think we need an agreed timezone for April fools jokes (AFAIK, people have always maintained that if you do your joke after April 1st, you are the fool - where does that leave slashdot?).
Well, the thing with the moon is kinda true. Heard a serious physicist say that the moon will crash into the earth in about 100 billion years (I made up that number don't remember what exactly it was) and that our sucking energy from its rotation through tidal dams will reduce that by a few hundred years.
Ok so I made up the 100 billion, I can never remember numbers but it was something along those lines maby it was 100 million but that sounds too short, shrugs.
at something like a inch a year. A long time ago the moon appeared to be far far bigger than it is now.
Muslim community leaders warn of backlash from tomorrow morning's terrorist attack.
The moon's mass is about 7.4 * 10^22 kg. The earth's mass is about 6.0 * 10^24 kg. The moon is about 3.8 * 10^5 km away. This works out to 7.6 * 10^28 joules of gravitational energy. Assume that the earth draws 10 terawatts of power from waves. (Our getting so much is a very dubious assumption, but it's fine for the sake of making estimates). This means that we can draw power at this rate for on the order of 7.6 * 10^15 sec before a macroscopic change in the moon's position would result; this time intervals which works out to about 240 million years. I would suspect that before a quarter of a billion years passes someone will have figured out how to solve the problem.
Who knows, perhaps we'll want to keep the moon closer to Earth for power generation purposes--the lunar tides would be alot stronger then, and ostensibly the energy-from-tides mechanism would be more efficient.
TheVoiceOfReason writes: "My main worry about "ask slashdot", is that we would put the earth in danger by accellerating the descent of human evolution by opening the forum to morons and their silly questions, since the readers would have to expend more energy in generating filters, and thus lose their will to live. How serious a problem is this? What are the solutions? Could we send a rocket up to give the editors a 'kick' once in a while?"
Happy April 1, kids.
No sig.
Well, I did want to mention this in my original post, that yes the earth is slowing down, but by far the greatest factor has to do with the very slow cooling of the earth's mantle and core. Not anything that mankind could do without some tremendous source of energy as of yet undiscovered.
I remember reading about it in geology class, but the exact reason escapes me. My memory is a bit hazy these days, you see.
Um, maybe you're correct, but I've always understood inertia to mean objects resting, moving, or traveling in a straight line and all that jazz. Whereas momentum had to do with the amount of force behind whatever is moving. Ah, whatever.
I meant to say "momentum" in place of "inertia" up there. Danged physics definitions.
Aren't they right? Really, The communists and the environmentalists are right about coal power plants. Nuclear power is less immediatly damaging, and many environmenatlists do not protest them.
I never argued that fossil fuel power wasn't evil. It's necessary, because it's pretty damned hard to build a nuclear plant with today's public outcry and the usual not-in-my-backyard syndrome.
Those same individuals who are picketing coal power plants for emissions reasons are also helping to prevent the construction of new nuclear plants through any number of activist means.
Many of which are advertised on websites.
Now, I find it interesting that they have no banner ads up begging for volunteers to pedal the stationary generating bicycles that power their servers. Ergo, I must conclude that their servers are powered by one of the coal or nuclear power plants they despise so much.
Hypocrisy is part and parcel of environmentalism.
(the problem with nuclear power is mainly one of public oppinion, not of "environmentalist" concerns).A measurable percentage of the North American population thinks Elvis Presley is still alive. Another measurable percentage thinks they've been on an alien craft. 20% think that the moon landings never happened. Every shopping mall has a lottery kiosk, and every newspaper has an astrology column.
So, you tell me if public opinion should be relevant.
Therein lies the failure of democracy.
Just because Americans are too PROFIT oriented to make any real attempts to work on/fund projects to find alternative sources of energy, does not mean that they do not existAlas, there are too many CEOs and CFOs who don't look beyond the next quarter's results. So? They will fail. They will not profit as handsomely as those companies who take the risk and push the edges. Eventually, they are doomed to fail through their own apathy, ineptitude and sluggishness, as they're forced to play R&D catchup or pay huge licensing costs for the new technologies developed by teir competition.
Examples? Look at Intel.
There is plenty of alternative energy research going on. Come on. Big Oil may be afraid of the huge infrastructure costs of moving over to some other primary energy source, but the stakes are so high that you'd better believe that they're going to try their best to maintain their current position. Esso/Exxon stations pumping vegetable oil instead of diesel fuel can still be profitable, they know that.
Besides, no transition of this magnitude can be done overnight, either. If the average car lasts ten years, then full capacity in the new fuel won't be needed for ten years. The transition would actually be spread over several decades.
Fire and Meat. Yummy.
Ok, I gota bitch about the Nuclear power plants NOT being a problem thing. Shit, where the hell have you been?? Ever heard of the Columbia river? That large one on the west coast, Lewis and Clark, all that?
Turns out it is now polluted by nuclear waste, not very nice. In another few years Hanfords storage bins are gona be leaking even more into it, what did the goverment say? Nothing, reported it, issue dropped.
Sure. And Three Mile Island blew up, also through mismanagement, and Chernobyl too, therefore, nuclear power will always be leaking stuff or blowing up plants and killing people.
Windows 2000 gave me a blue screen. Therefore, there's no way that computers can ever be stable, so we shouldn't use them.
Heh, nice to know.
Yup. Nice to know.
You see, nuclear power plants create waste. ALOT of waste in fact, a whole lot of very DANGERIOUS waste.
One pellet of U-238 dioxide, a cylinder of black ceramic 1 centimeter in diameter by 1 centimeter long, over the year it stays in a CANDU nuclear reactor, will produce more energy than burning a ton of coal.
Shit, coal, hell, say inside, where a gas mask, you can DO something about air pollution, or at least you can avoid it.
Sure. You can stop breathing. Because as you burn that ton of coal, it combines with several tons of the gasses that make up air.
One ton of coal leaves the chimney as several tons of sulphur dioxide and carbon dioxide. Not to mention the soot. Ever been downwind of a coal plant?
But that little pellet is never more than the little pellet.
Heh, Lead Clothing is about the only way to escape from radiation.
Or keeping the radioactive material far away from human contact. Maybe lead clothing for the radioactive materials? Stopping breathing air and drinking water are the only ways you'll be able to avoid the SO2, CO2 and soot from a coal plant.
Any better ideas there, sport?
Thrall me with your oh-so-evident acumen.
Fire and Meat. Yummy.
As he was trying to explain this apparent trajedy to me, he got pretty pissed because I had fallen off my chair laughing. Oh, where would we be today without people like this to provide us with this sort of knee-slapping hilarity...
Alas, voting is a right bestowed on the gullible simpletons, too. The only failure of democracy is that everyone gets a chance to be heard, even if they're simply wrong.
Fire and Meat. Yummy.
Some of it sucks, some of it doesn't - just like Slashdot on any other day. Jeez.
sulli
RTFJ.
If the moon descends to the point that it crashed into the sea, then a gigantic tidal wave would cause an enormous power surge in all the sea- and wave-powered electricity grids.
But things would settle down after that.
I am anarch of all I survey.
Eventually the Earth will be tidally locked to the Moon as the Moon already is to Earth. At this point IIRC the Moon will be about 350,000 miles out (rather than the 250,000 it is now). Isaac Asimov ran all this out in an essay in A Choice of Catastrophes.
Brackets contain world's first nanosig, highly magnified:[.]
however lame the april fools joke was, i was still interested and looked around a little. here is a link to an article by msnbc:
http://www.msnbc.com/news/493172.asp?cp1=1
overall i think it was pretty good for the mildly curious
The long and the short of it is:
- The Moon is moving away from the Earth. This has been known from first principles for centuries and has been measured directly by laser ranging ever since Apollo 11 placed retroreflectors on the surface.
- The cause has nothing to do with any change in gravity. The gravitational pull between Earth and Moon is decreasing because of the increase in Earth-Moon distance.
- The reason the Earth-Moon distance is increasing is because the Earth's spin is being transferred to the Moon via tidal forces.
- The faster-spinning object (Earth around its own axis) is slowed down,
- the slower-spinning object (Moon around Earth) is accelerated, and
- the acceleration raises the Moon into a higher and slower orbit.
- There is plenty of historical evidence for the slowing of the Earth's rotation; there are fossils showing daily and annual cycles from a few billion years ago, and at least one of these shows a 400-day year; Earth was spinning about 11% faster in those days.
I hope that clears up a few things.--
Give a man a fish and he eats for a day.
Scientists restrict study to entire physical universe; creationist
Let's generate power from goat sex!
You know it's been a boring day on slashdot when that gets moderated "Interesting."
Not "Funny", no, no, that's "Interesting."
Yowch.
I remember /. on April 1st for the past several years or so was great. There were stories posted for April Fools that were just hystical (like the Seattle riots with the guy shouting "Death to all GUI's!!" as he was being dragged off by police). This is just getting out of control. The whole point of an April Fools joke is that it's not evident until *after* the fact (basically, you fooled someone into believing something false). This stuff is pitifully obvious. So stop. Please. Yes, the All Your Base thing was funny because it was blown out of proportion. It is NOT likewise for /.
Why bother.
The real problem is the damage we're going to cause with the slingshot effect. Sure, it sounds like a good idea, stealing momentum from a planet to send our satellites to others...
But every action has an equal and opposite reaction: we're sending planets hurtling back the way the satellites came!
--
I'm sorry, but damning water is insignificant compared to the millions of holiday travelers distributing their fat mass South every winter and moving right back North to their summer homes *every* year.
This is going to swing the earth's seasons off balance and this planet is going to be spinning in two directions.
Being here in California where we're more reliant on wind power than tidal power (and we've all seen how reliable that is recently), I'm more worried about the proliferation of wind farms around here. I mean, what happens when we've farmed all the wind? Most of the weather patterns for the entire United States start in the Pacific and travel via the wind eastward over the country. If we use all the wind here in California for power, suddenly all those clouds and the jetstream and stuff will stop here, the rest of the country will get sucked into a terible drought and pilots won't be able to make up for the late departure from SFO to JFK!
Think about it, the US will be devistated, the dot-com stocks will crash taking the economy with it, the country will go into uncontrolled recession, the free world will fall and the commies will take over. At least if the moon were to fall, NASA could send it into some uninhabited part of the Pacific Ocean, just like they did with MIR.
I always figured that the April 1 stories are nothing but an excuse for the editors to get back at people like you. Frankly, I'm amazed that there are so many people reliant upon slashdot. You might want to think about all the other days you're dissing the regualr stuff before bitching that you want it back now.
"We obviously need a new moderation category: (-1, Woo-fucking-hoo)" --Mr. AC
Now THAT is class. Someone who takes April 1 so seriously that they even redo their banner ads.
Funniest stuff I've seen or heard all day.
The moon is spiraling away from the earth, not towards that. The little elf on the other side of my mirror told me so.
This question belongs in April 1, methinks.
The Moon is receding from Earth, and doing so rapidly enough that that their surfaces would have been touching about a billion years ago. The infinitesimal amount of wave and tide energy that we can extract, even if we work on every section of coastline, woun't even slow this recession down noticeably. Plain, ordinary vannilla-flavoured physics is slowing the recession several orders of magnitude faster than we eevr could.
BTW, lightning damage (like Schroter's Valley) and other more or less Transient Lunar Phenomena hint that dear old Luna isn't as inactive as has previously been thought.
Got time? Spend some of it coding or testing
Maybe the catch is still to come tomorrow or so, A poll with the questions
:)
o one of the stories posted on april 1st was serious?
o one of the stories was remotely funny
o I submited all stories posted april 1st
o Huh? Did they post anything different then usual?
Must admit, im gonna have trouble picking my vote
-- Chris Chabot
"I dont suffer from insanity, i enjoy every minute of it!"
This reminds me of something funny I once heard a few years back. I was talking to one of my dad's friends who was postively convinced (and just a little drunk) that mankind was slowing down the rotation of the earth by launching lots of rockets and space shuttles from it.
I shit you not.
Nevermind that a rocket's thrust is completely insignificant in any timeframe compared to the inertia of the earth. And that they take off vertically rather than horizontally.
As he was trying to explain this apparent trajedy to me, he got pretty pissed because I had fallen off my chair laughing. Oh, where would we be today without people like this to provide us with this sort of knee-slapping hilarity...
Sitting is making the laws of gravity work harder, so they will have to stop soon sending us all out into outer space except for those who grab onto something who will have the joy of plumetting into the sun as the orbits misalign spelling death for everything.
You know, the really sad thing is, tomorrow's stories won't be much different.
Or else I'm going to seriously gripe about my article on "the courtship and mating dances of orange and black umbrellas" not getting posted.
political_news.c: warning: comparison is always true due to limited range of data type