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Energy From Raindrops
conlaw writes to share that according to Discovery.com scientists have found a way to extract energy from rain. A new technique could utilize piezoelectric principles of a special kind of plastic to generate power from falling water in rainstorms or even commercial air conditioners. "The method relies on a plastic called PVDF (for polyvinylidene difluoride), which is used in a range of products from pipes, films, and wire insulators to high-end paints for metal. PVDF has the unusual property of piezoelectricity, which means it can produce a charge when it's mechanically deformed."
well, that's not exactly the galt engine, but it sure smacks of that sentiment.
Any guest worker system is indistinguishable from indentured servitude.
One for the floor of your shower.
Buanzo Consulting - 15 Years of GNU/Linux experience, for you.
The amount of rain we get here. :-)
If I had an Ass, I'd call it Fanny Bottom, then I could slap my Ass; Fanny Bottom, on the Arse.
Seriously though, Portland is trying to gain the title of the renewable energy capital of the United States and this would be awesome in the whole Pacific Northwest as they slowly ween themselves off the major dam systems they build up over the past 80 years.
An Education is the Font of All Liberty
These things don't generate much energy, but should be enough to power a perpetual tiny rendition of Gene Kelly' 1952 hit film.
You are quite wrong, treadmills have been used in the past to power all sorts of things. Here is an example:
http://www.uic.edu/aa/college/gallery400/notions/histories.htm
"The hospital of Bicêtre, France boasts a prodigiously deep well underneath, dating from 1735. The horizontal wheel that pumped the water was turned
initially by twelve horses, then, starting in 1781, by 72 men, taking shifts on a 24 hr day. These workers were eventually replaced by epileptic
patients and "madmen" in residence at the hospital."
I would also challenge the notion that fluorinated plastics can be produced energy efficiently enough to actually produce an energy surplus by collecting raindrops. I might be wrong
though, but out of laziness I'll leave the proof to somebody else.
Je me souviens.
Or just collect the water and run it through a water mill. WTF??
Whatever happened to water wheels? We have been using them for thousands of years.
If they put this stuff on the floor around the urinals at my local bar, we could meet Canada's energy needs for the next hundred years.
I've calculated my velocity with such exquisite precision that I have no idea where I am.
Anything that moves can produce energy. The point is how much and at what cost to capture and reuse or store. I can solar panels on my roof for about 15K that averages about $120 a month. About a 10 year payback. A wind turbine that generates about 20% of my needs would cost 5K and have a payback of 15 years. Strapping a motion generator to myself and family to produce enough power to charge cell phones doesn't appear to ever justify the initial cost. Raindrop system.... call me when it costs the same as a shingle.
... but whether this means it really produces power from water vapour, or is an idea they cannot implement is unclear.
Let's build a very large vat. I mean it has to be huge. Then collect lots of rainwater in it, and stick a mechanism that changes outflow into something that can be used to spin a generator. Boom, electrical energy from rain!
Of course this is still just indirect-indirect-indirect solar power, as always. But jeez, do you have to make things so complex by default? Is this the "innovation-promoting" effect of patenting?
I have one powered by a generator attached to my knee joint. One to a string vibrating in the wind outside. One to my hamster. I'm seriously running out of cell phones by now. I'm starting to feel guilty not using more of this green energy.
I would think the most obvious application would be as a lining for highway and rail beds, maybe even sidewalks and streets in some places. True, the variations in traffic load would determine your capacity for a C/B analysis to decide where to install the systems but if the carbon cost to manufacture the material is offset by the by the "carbon-less" power generated (discounting vehicle consumption), then why not take advantage of all that free vibration? I can see where this might be able to generate substantial amounts of power in major metropolitan areas either for direct consumer consumption or to run latent and ubiquitous powered infrastructure like traffic signals (with a grid back up, natch).
This energy is just drops in the bucket compared to what they could get from lightning.
...this breakthrough comes after failed attempts to generate power from roses, whiskers on kittens, bright copper kettles and warm woolen mittens.
These are a few of those researchers favorite things.
Paul Lenhart writes words!
THE RAIN
--found in Architect's Creek Hut, Westland Nat'l Park, New Zealand
It rained and rained and rained
The average fall was well maintained
And when the tracks were simple bogs,
it started raining cats & dogs
After a drought of half an hour
We had a most refreshing shower,
And then most curious thing of all,
A gently rain began to fall!
Next day but one was fairly dry
Save for one deluge from the sky
Which wetted the party to the skin
And then, at last, the rain set in.
A typical raindrop has a fall velocity of about 8 m/s. Assuming a pretty healthy rainfall of 10cm (4 inches) we get 100 liters of water per square meter of land. 100 liters of water weighs 100kg, of course, and plugging that into the equation for kinetic energy gives us 6400 joules. Spread out over 2 hours, that's a whopping .89 watts per square meter.
All of that assumes 100% conversion efficiency and no losses due to standing water absorbing the impact of the drops. If the overall efficiency is, say, 50%, then you'd need something like 30 square meters to light a single compact fluorescent bulb. To generate a megawatt would require over 2 million square meters (over 500 acres).
Given that in most places it rains less often than the sun shines, this seems like an astonishingly inefficient way to generate electricity. There just isn't that much energy in rainfall.
Just imagine: if this stuff panned out, it would not only be rain that could deform it. It could be deformed by say birds walking on it (toughen it against claws). So instead of cities trying to actively chase pigeons away (some places chase them on the ground with dogs and in the air with falcons, etc.) and the "don't feed the pigeons" signs - you would instead see "feed the pigeons right HERE." (where the special plastic is). Hopefully they get some of that rain working for them to, to wash the pigeon poop off the plastic though.
This is more newsworthy as an arcane Rube Goldberg method of extracting energy than as anything remotely practical. You could extract more power by implanting braces of dissimilar metals in the mouths of two teens, then forming a battery when they kiss.
Why not put into floors of buildings, that way the building get energy from people walking around. Also put in in sidewalks that way the same principal would work for people walking on the street.
sudo mod me up
Collecting the heat energy of the gasious output of your local politicians would gain much more energy for free. You only have to convince them to speak into the pipe of your selfmade heatcollector instead of the microphone.
You are not entitled to your opinion. You are entitled to your informed opinion. -- Harlan Ellison
Now, if they could get energy from steam, THAT would be vaporwa... oh wait, nevermind.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
This isn't the first I've heard of using piezoelectrics to collect power from rainwater. The last one was actually using a separate piezo element under a plastic sheet. Maybe the two research teams aught to put their heads together and try to double their yeild? P.S. Even if it's not a massive surplus, every little bit helps!
This stuff would be great for my lighted clear plastic raincoats!
www.clearplastic.com
Cleara
Um, don't we already do this? I mean hydroelectric dams harness the power of rain as it flows from higher elevations to lower elevations.
Do you mean hydroelectric power isn't renewable? Hydro power *is* energy from raindrops, where do you think the water in the rivers came from?
It seems quite possible to harness power from rain. We can harness the sun on a sunny day for solar energy. We can harness the wind on a windy day for wind energy. We can harness the ebb and flow of the oceans based on the moon's position for tidal energy. So why not harness the rain on a rainy day, the snow on a snowy day, or lightening on a stormy day?
Two things to consider is location and time of year. Imagine solar and wind energy powering much of Arizona during the dry season and weather energy ("Meteorelectricity") durring the monsoon season.
It sounds good in theory.
The Rapture is NOT an exit strategy.
Actually, considering that large buildings are designed to sway, it would indeed be possible to generate power at the top by putting a heavy weight there and generating power as it moved with respect to the building.
Of course, the problem is that a weight that could generate a meaningful amount of power would unbalance the building as it slide from side to side.
If corporations are people, aren't stockholders guilty of slavery?
I thought about using piezo material years ago. Weather dependent energy devices are iffy at best, wind and solar are too intermittent. Why not harness all the sidewalks, roads, dance floors where vehicle and foot traffic abound. Feet pounding the pavement seem more reliable that raindrops.
patients and "madmen" in residence at the hospital."
Wasn't this kind of thing shown in the movie Midnight Express?
Oh Amen to that one!
The rainiest place in Europe is near Inverness - that's why Loch Ness is so big.
Going back to the story though, wouldn't it be much better to put this stuff in the sea? Somewhere where waves crash a lot...
No sig today...
for some values of no-one
There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
"the unusual property of piezoelectricity, which means it can produce a charge when it's mechanically deformed"
... microphones and speakers. Oh wait, been there done that. Or use it to light natural gas/propane stoves. Oh nevermind.
What, never had a crystal radio? Kids these days. Piezoelectricity isn't so unusual. You can go buy many products using it. Even at outfitters (read: outdoors and camping stores) you'll find plenty of devices using piezoelectricity. Given that we've known about it from the late 1800's that isn't unusual either. Some sugars, bones (let them dry first), ceramics, and many crystals are piezoelectrical. Oh and get this we can reverse it. Maybe we can use it to make
A while back someone (MIT?) tried to use this precise method (and material IIRC) to make power from floors at subway stations.
I could go on, but perhaps you should try Wikipedia. If they don't already have a nice article on it, I'm sure one will follow fairly quickly.
Nothing unusual about either piezoelectricity or the material used in the story.
My Suburban burns less gasoline than your Prius.
Everything has energy, and that can be converted to electrical energy.
Electricity and water.
What could possibly go wrong?
YEAH??? Well... shit, you're right. U.S. beer *is* like making love in a canoe: Fuckin' close to water. Damn it, the truth hurts.
Take the 90-Day Challenge! http://rwmurker.bodybyvi.com/
No way. Vancouver or just about anywhere else no the Pacific Northwest would have unlimited power.
And by the way, my Dad is from Lincoln.
If you don't want to repeat the past, stop living in it.
Vancouver or just about anywhere else no the Pacific Northwest would have unlimited power.
If you mean the westernmost part of the Pacific Northwest, that's true. But inland, across the mountains, the Pacific Northwest is very dry, with some parts seeing less than seven inches of rain per year.
Remember what they say about generalisations: they are generally wrong.
Oh, but that's right: electricity for my 52 inch plasma screen is more important.
RS
Shoes for Industry. Shoes for the Dead.
My organic instructor was a serious mathaholic, in class she demonstrated on the board to the class that 1 inch of rain falling on Manhattan released the same amount of energy as a 15 KT nuclear explosion.
Apocalypse Cancelled, Sorry, No Ticket Refunds
Power Surge, baby. Power surge.
Linux - Because Mommy taught me to Share.
I kind of like the idea of using gym equippment to generate energy. I'm no physisist by any stretch of the imagination but even though the energy, to my understanding, created by one individual may seem negligible, the collective energy produced could at least reduce something's power consumption.
If I recall correctly wasn't a half an hour of the Superbowl's pregame show's energy produced by humans working out on stationary equippment?
I wouldn't want to rely on this means of generation to power critical devices, but I do believe that we should start taking steps to optimize energy production and take every little bit we can.
A penny saved is a penny earned so to speak...dig?
----
Fool me once, shame on you. Fool me twice....Ooh! That's a real Rolex you say?
Howe due yoo keap uh gramur natsee bizzy four ours?
What will they think of next?
...it would be far much easier to just build a dam and a waterwheel to harness the energy of rain.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
Wouldn't the pressure of the wind (assuming flurries of wind instead of a constant wind) do pretty much the same thing as the pressure of a rain drop? Put it on an angled roof and you'd get solar power, rain power, and wind power all in one. Use these things instead of shingles. If we could make these things tough enough then we could replace all sidewalks with these things and also make use of walking energy.
Cow Cube
I call dibbs on rain-gutter downspouts :)
Apocalypse Cancelled, Sorry, No Ticket Refunds
British prisons used to do it. Though the amount of work you can get from humans is so low that they mostly wasted the energy by attaching vanes to the mill that made it harder for the prisoners to work.
http://space.newscientist.com/article/mg16322007.600-the-last-word.html
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
This is extremely silly. There's not much energy there, larger amounts can be gathered trivially.
Falling raindrops reach terminal velocity after aproximately 5-10 meters, assuming they're the large type. Tiny raindrops reach terminal velocity after something like -1- meter.
So, if you could somehow collect the entire energy (not possible most of it goes into heating the drop as it's vigorously stirred on impact) you'd have collected the same energy as for the water falling perhaps on the average 3 meters.
Let's say your house has a 100square-meter roof, and you install this magical capture-all-energy stuff on the entire roof. Let's furthermore say it rains 1000mm/year. You have now collected the energy of 100 cubic metres of water falling 3 metres. That is 100*1000*9.8*3 = 3000KJ. Or sligthly less than -1- Kwh.
Market-value for this power at grid-prices ? $0.10.
Market-value for this power from a solar-cell ? (say if there's no grid available) $2.00
Price for a wind-turbine that will deliver 1Kwh/year ? You'd take the smallest one you can get, probably one from a kids toy. We're talking an average of 0.1W here....
Adding insult to injury, the power comes at semi-random impractical times, not when you need it.
Conclusion: Even *IF* you wanted this tiny amount of power, and it MUST be from rain, you'd be better off installing a tank at your roof, and a small turbine in the downspout. That way you could drain the same power (assuming your roof is 3 meters up) and it'd cost less and work better.
Extra-conclusion: Everything is in reality atleast 10 times worse than I state here, because this all assumes the material can magically convert 100% of impact-energy to electricity, which is obvious nonsense, I'd be impressed if it could do 10%...
I wonder how much energy could be harvested from rain water flowing through drain pipes? Maybe little water wheels stacked one above the other?