Electrical circuit runs entirely off power in trees
From the University of Washington by Hannah Hickey hickeyh@u.washington.edu
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| University of Washington |
| Electrical engineers Babak Parviz and Brian Otis and undergraduate student Carlton Himes (right to left) demonstrate a circuit that runs entirely off tree power. |
You’ve heard about flower power. What about tree power? It turns out that it’s there, in small but measurable quantities. There’s enough power in trees for University of Washington researchers to run an electronic circuit, according to results to be published in an upcoming issue of the Institute of Electrical and Electronics Engineers’ Transactions on Nanotechnology.”As far as we know this is the first peer-reviewed paper of someone powering something entirely by sticking electrodes into a tree,” said co-author Babak Parviz, a UW associate professor of electrical engineering.
A study last year from the Massachusetts Institute of Technology found that plants generate a voltage of up to 200 millivolts when one electrode is placed in a plant and the other in the surrounding soil. Those researchers have since started a company developing forest sensors that exploit this new power source.
The UW team sought to further academic research in the field of tree power by building circuits to run off that energy. They successfully ran a circuit solely off tree power for the first time.
Co-author Carlton Himes, a UW undergraduate student, spent last summer exploring likely sites. Hooking nails to trees and connecting a voltmeter, he found that bigleaf maples, common on the UW campus, generate a steady voltage of up to a few hundred millivolts.
The UW team next built a device that could run on the available power. Co-author Brian Otis, a UW assistant professor of electrical engineering, led the development of a boost converter, a device that takes a low incoming voltage and stores it to produce a greater output. His team’s custom boost converter works for input voltages of as little as 20 millivolts (a millivolt is one-thousandth of a volt), an input voltage lower than any existing such device. It produces an output voltage of 1.1 volts, enough to run low-power sensors.
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The UW circuit is built from parts measuring 130 nanometers and it consumes on average just 10 nanowatts of power during operation (a nanowatt is one billionth of a watt).
“Normal electronics are not going to run on the types of voltages and currents that we get out of a tree. But the nanoscale is not just in size, but also in the energy and power consumption,” Parviz said.
“As new generations of technology come online,” he added, “I think it’s warranted to look back at what’s doable or what’s not doable in terms of a power source.”
Despite using special low-power devices, the boost converter and other electronics would spend most of their time in sleep mode in order to conserve energy, creating a complication.
“If everything goes to sleep, the system will never wake up,” Otis said.
To solve this problem Otis’ team built a clock that runs continuously on 1 nanowatt, about a thousandth the power required to run a wristwatch, and when turned on operates at 350 millivolts, about a quarter the voltage in an AA battery. The low-power clock produces an electrical pulse once every few seconds, allowing a periodic wakeup of the system.
The tree-power phenomenon is different from the popular potato or lemon experiment, in which two different metals react with the food to create an electric potential difference that causes a current to flow.
“We specifically didn’t want to confuse this effect with the potato effect, so we used the same metal for both electrodes,” Parviz said.
Tree power is unlikely to replace solar power for most applications, Parviz admits. But the system could provide a low-cost option for powering tree sensors that might be used to detect environmental conditions or forest fires. The electronic output could also be used to gauge a tree’s health.
“It’s not exactly established where these voltages come from. But there seems to be some signaling in trees, similar to what happens in the human body but with slower speed,” Parviz said. “I’m interested in applying our results as a way of investigating what the tree is doing. When you go to the doctor, the first thing that they measure is your pulse. We don’t really have something similar for trees.”
Other co-authors are Eric Carlson and Ryan Ricchiuti of the UW. The research was funded in part by the National Science Foundation.
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Maybe a grove could power a cell phone tower??
HAHAHAHAHAHAHAHAHAHA
I remember that they sold clocks in the 80ies that were running on lemons
“similar to what happens in the human body but with slower speed”
Then stick ’em in humans…. Just imagine the power you could harness off the obese.
“There seems to be some signaling in trees, similar to what happens in the human body”
Trees got brains?
What’s with this ‘peer-reviewed’ prefix ?
The godamn device either works or it doesn’t work.
Next up: peer-reviewed sports results followed by an advert for a peer-reviewed sandwich-maker.
I find it works better if you put electricity into the electrodes, then add air to the wood…
A bit of sparking and PRESTO, lots of thermal power 😉
So, there are 5,967 quintrillion trees and shrubs on Earth, and each produces .002+V constantly.
Let’s wire each tree and shrub up in series, and we will have an electrical energy potential (pardon the pun) far surpassing all of the greenhouse poison gas producing coal-fired death station generation in existence.
Think of the children!
Why can’t we do this, right now? It must frighten Big Oil.
This is the third thread in recent weeks where I have read it and thought ‘but I knew that years ago.’
Fifty years ago our teacher did a similar experiment with some of the trees in the school grounds. As a class we also built our own clocks powered by a potato (the poor kids) and lemons (the rich kids).
It seems that as a society we forget the things that happened in the past-like previous civilisations that had temperatures warmer than todays.
tonyb
‘Then stick ‘em in humans…. Just imagine the power you could harness off the obese.’
isn’t that the plot of The Matrix ?
Might as well use power from trees. The Solar Panel market is all backed up on account of nobody has the money to buy them. Goodbye green jobs.
China can produce them much cheaper than the US, so goodbye Solar Panel industry.
Does this come in a kit?
E.M.Smith (01:48:04) :
I can’t see my monitor… it won’t hold still and I can’t stop laughing.
Oh Jeez.
I always suspected it took electricity to make a tree ring.
‘Nature’ works with a minimum cost for survival. Tapping the electricity of a tree could require the tree to try to compensate for the loss thereby reducing its chances for survival.
PS ‘minimum’ is actually the ‘maximum’ that a tree can devote without calling upon other resources neccessary for its survival.
The lemon, potato or tree (as I understand it) just provides the electrolyte (a liquid that conducts electrical charges). The actual energy comes from difference in potential between the two different metal electrodes which slowly get used up (as in a battery) – so any energy that you get out was put in by refining the metals in the first place.
You have to ask – what is being used up (hint – not the tree)?
I wonder if they are using copper nails, hopefully for the trees they aren’t.
oops – I see they used the same metals for the tree experiment – ok! But the lemon and potato clocks use different ones.
I rather suspect the tree will react over time, probably encysting the electrode?
I notice they used electrodes of similar material to avoid setting up an electrode potential (like the Daniel cell – copper and zinc) but there are other effects giving rise to potential differences such as ionic concentrations in the half cell and very importantly oxygen concentration. Even differences in temperature have an effect.
E=E0-RT/zF*ln(a1/a2)
Never mind the volts, what about the amps?
And anyone know the voltage potential of a grape vine? I can see an eco-power campaign based on bad puns and cheap French vineyards here, and with sufficient envirosubsidies, free booze for visitors!
Link to the original article.
http://uwnews.org/article.asp?articleID=51869
lol a nanowatt, boys better get cranking spiking those trees, you might generate a few watts by 2100 AD.
Atomic Hairdryer (03:49:50) :
“Never mind the volts, what about the amps?”
From the info in the article I would guesstimate it will be around 1.0 × 10-8 amps – not going to take-over from fossil fuels any time soon, unless they find they can get more amps come from currant bushes 😉
“E.M.Smith (01:48:04) :
I find it works better if you put electricity into the electrodes, then add air to the wood…
A bit of sparking and PRESTO, lots of thermal power ;-)”
In Australia we won’t need anything as elaborate as this to start a fire, just a fuel laden forrest, and a spark, usually man-made.
So? I recall similar tests back in the ’60’s demonstrating that plants scream when cut. Another “So?”. What, precisely, is the usefulness of such knowledge (other than busy work)? If it leads to better crop yield, or weed/pest control great, otherwise why care?
Perhaps this could be used to develop a new set of temperature sensors with an autorecorder, perhaps a flash drive, that could be downloaded periodically. Would this fit with the siting requirements of NOAA?
Hmm, if a tree rings in the forest, who picks up?
Please don’t stereotype tree huggers.
Some of us are global warming skeptics.
Mike McMillan (02:26:33) :
I always suspected it took electricity to make a tree ring.
Fantastic!
F Rasmin (02:27:39) :
‘Nature’ works with a minimum cost for survival. Tapping the electricity of a tree could require the tree to try to compensate for the loss thereby reducing its chances for survival.
F Rasmin (02:32:04) :
PS ‘minimum’ is actually the ‘maximum’ that a tree can devote without calling upon other resources neccessary for its survival.
Ummmmm….. so you think we’ve never done this in tha past with any plants?
Rubber trees?
Maple trees?
Opium poppies?
Need I go on? We are very, very good at ectracting what we want from plants and keep them very, very much alive. Because of that we have loads of:
rubber
elastic
maple syrup
heroin
‘scuse fat fingers
Curious. I remember reading a couple decades ago research that found electrical impulses in plants that looked like a slowed down neuronal impulse. (It was part of a larger topic of plant communication looking into how when one plant is attacked by a pest it and neighboring plants produce the same defensive reactions. Most of that was a chemical transport by air and ground, the neuron-analog was more of a curiousity.)
Let’s see, here are a couple recent sources. Ah, keyword neurobiology. There’s a lot of stuff at http://www.plantbehavior.org/ but maybe not relevant to this topic.
This may be a bit of a wacko source, hmm, maybe okay. Expensive book. http://books.google.com/books?id=IH9N4SKWTokC&pg=PA19&lpg=PA19&dq=plant+neuron+communication&source=bl&ots=TezladlI5s&sig=Q9elUvSh-g90skFUZxxUxz3K4Vk&hl=en&ei=DbKnSr-FKpSalAfr_s2AAQ&sa=X&oi=book_result&ct=result&resnum=3#v=onepage&q=plant%20neuron%20communication&f=false Don’t be surprised if that URL fails, it’s from searching for plant neuron communication. Ah, I can copy the overview:
Also, http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2K-4RRFNGF-2&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1005864006&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=14d5443ad94601fc820d17a24f7d65f2 says:
It all seems like a lot of work for a tiny amount of power. I wonder if they might do better with a piezoelectric device that converts energy from wind and diurnal movements of branches. Even a small solar cell might be better, though likely more expensive.
@ sequoiatreehugger (06:40:24) :
“Please don’t stereotype tree huggers.
Some of us are global warming skeptics.”
Well that’s good to know. Btw, I own several thousand trees. I’m also a woodworker, so I cut them down as needed. Trees are a renewable resource to be used, not worshipped.
What happens when lighting strikes?
@ Ric Werme (07:08:59) :
Ric, thanks for the feedback. If it leads to improved yields, etc. then good. I know basic plant research has been of great value in that, but to focus research on power generation from plants seems a bit silly to me, unless it can be enhanced to more efficiently and economically zap the many pests that destroy valuable crops, than present methods.
Why not to use artificial trees instead?
Look at this: http://www.giurfa.com/artrees.html
Ron de Haan (07:29:41) :
What happens when lighting strikes?
That’s a very interesting question. What about the electric capacity?
Yes, and I had a crystal radio when I was a kid. So what?
I wonder if the tree is acting as an antenna for environmental Electro-magnetism? Turn off the hi tension wires and radio/tv/cell towers in the area and poof, there goes your signal.
Ruth (02:45:31) :
There are several types of electrolytic cells and one of them is well known… the two different metals in a common electrolyte. Another is when you use the same metal but with different electrolytes. You just need a conductivity bridge or a membrane to separate them. The different environments around the electrodes will generate the difference of potential. To illustrate this you can even use the same electrodes in the same electrolytes (also separated by a membrane of a conductivity bridge but at different concentrations. That too will generate a difference of potential.
Under those same principles, you could stick an electrode in your a$$ and another one in your mouth and get a difference of potential.
I don’t think that guy will get a Nobel Price for this… on the other hand, they gave one to Al Gore… so it’s possible after all that he will get one.
>There seems to be some signaling in trees, similar to what happens in the human body
They better be careful with this technology. The talking trees might go to war.
What a crock; when I was eight years old I was powering electronic circuits with electrodes stuck in apples, oranges, lemons, pears, rhubarb, probably bananas, and maybe some fruit I have forgotten about; many of which grow on trees. I’m sure I tried passion friut and Chinese gooseberries (Kiwi to you); but those two grow on vines.
Can I get a PhD this long after doing my research ?
Can you get an Obamaloan to stick nails in the trees in your yard. Hopefully this paper will derive an AlGorythm for computing the horsepower versus tree height or weight, so we can figure out how big a tree we need to power our houses.
Sounds more interesting to me that Steve Chu’s microbe/yeast power plant.
George
Wow! Just think, this finding will someday be very important to the Christmas Tree farmers of America. With advances in electronics and genetic modifications of Balsam firs, Douglas firs and the spruces and pines, live trees will come self -lighting. A new meaning for “lit up like a Christmas tree”!
George E. Smith (09:46:28) :
The article makes it clear they are not doing what you did:
The tree-power phenomenon is different from the popular potato or lemon experiment, in which two different metals react with the food to create an electric potential difference that causes a current to flow.
What you did generated much more power, but at the expense of the electrodes,
not so much the electrolyte in the fruit.
The most efficient electrolytic substance, for a variety of reasons, is beer. What we need is more beer. I’ve been saying this for years. Truly the best solution. It’s time to jump on the beer wagon for the salvation of the planet.
Tesla, IIRC, demonstrated electrical power flows between earth and air, varying with altitude, among other things. Commercial amounts of power have yet to be extracted. Almost equal areas of a tree are in the ground and in the air. Might the potential discovered be little more than the voltage drop across the tree’s resistance in the air/ground circuit?
Fred Harwood (11:55:44) : You are right. Go to the link I gave in my post above: Nogw (08:15:06) :
I recall reading that Edison had a water pump which pumped a small amount of water to a tank on the roof of his house whenever someone opened his gate. What a great idea.
Just attach generators to the turnstiles where there are turnstiles, and put turnstiles where there aren’t any at present. People going through the turnstiles would generate lots of electricity if the turnstiles were connected to generators.
Then too, we could make it so sidewalks were constructed of separate sections which could go up and down a bit when walked on, and the up and down movement, as people walked on them could be used to generate electricity.
No end to possibilities. I wonder how much power blinking eyelids could generate.
I hear Current Bushes are the best sources.
I carry a spare fern for my phone when I travel..
Groan….
@ Mike D. (11:34:45) :
“The most efficient electrolytic substance, for a variety of reasons, is beer. What we need is more beer. I’ve been saying this for years. Truly the best solution. It’s time to jump on the beer wagon for the salvation of the planet.”
I’ll drink to that. In fact there’s some evidence that Noah and family survived the biblical flood on beer (assuming you buy that story ). It’s full of nutrition and the alcohol kills germs. Much better than drinking dirty river water full of whatever. We’re not talking the watered down AB beer here, but full bodied REAL beer. 🙂
Watch out or the trees will attack. Just ask M. Knight Shyamalan (The Happening)… 8^)
Most likely the power is being produced by a concentration cell as there is a high concentration of various ions in the tree and low in the soil. Concentration cells are easy to build: take a tall glass, strip part of the the insulation off a wire and put it on the bottom of the glass and then cover it with salt and then fill the glass with water and put another wire into the water at the top of the glass hook up a voltmeter and one sees a voltage of a few hundred mv. This voltage slowly declines as the concentration gradient between the bottom of the glass and the top disappears as the salt concentration becomes equal in the column of fluid. I first made one of these when I was about 10 years old and thought it was really neat back then but haven’t thought much about this phenomenon since then until I saw this posting.
I guess working with first relay logic then TTL in my younger days made me ignore any source of micropower but with microprocessors now available that can run on microwatts I might give the old concentration cell a second look. In a tree presumably the concentrations are maintained by photosynthesis so one gets a steady source of very low current power.
Plants are rather boring electrophysiologically as I found out one night in the lab when I decided to record electrical activity from a plant that happened to be sitting on the windowsill. Lots of slow mv amplitude potentials that I assumed were injury potentials when I stuck electrodes through the leaves but nothing of the complexity I got recording from the mouse brainstem cultures I was working on at the time.
Wow, you must have REALLY long arms! 😉
Third generation bio fuel production will make use of wood.
http://www.biodieselfuelonline.com/Biodiesel_Made_From_Wood_Chips.html
Ric Werme 07:08:59
So, if plants are found to be sentient beings, what will the vegetarians eat?
A Lovell (14:27:31) : They will greenly recycle themselves.
Nogw (14:27:30)
I can’t wait 🙂 What a delicious (excuse the pun) dilemma……..
“”” Ric Werme (10:42:32) :
George E. Smith (09:46:28) :
What a crock; when I was eight years old I was powering electronic circuits with electrodes stuck in apples, oranges, lemons,
The article makes it clear they are not doing what you did:
The tree-power phenomenon is different from the popular potato or lemon experiment, in which two different metals react with the food to create an electric potential difference that causes a current to flow.
What you did generated much more power, but at the expense of the electrodes,
not so much the electrolyte in the fruit. “””
Well Ric, I have no idea whether you have ever done any analog circuit design or engineering; specifically highly sensitive operational amplifier circuits. If you had, then you would know that one of the single biggest problems in high precision op amp sensing circuits, is the elimination of spurious offset Voltages of Currents. People who have done that, know that absolutely any difference or assymetry in the circuitry associated with the pair of input terminals, whehter it be different elements, or temperature differences, or magnetic fields or any other discrepancy between the positive input, and the negative input, will always result in an offset error; in other words the eastablishment of a signal that depends on the simple fact that the two terminals are not directly connected to the exact same point in any physical environment.
Ergo, I’d be surprised if you stuck electrodes of any kind into any thing, and couldn’t get a difference signal between them. And if you allow a current to flow in that circuit, then whatever is establishing the differential will be physically modified in an attempt to remove the assymmetry (Le Chatalier’s principle); ie something is going to deteriorate somehow.
One of the major issue with electrolytic cells is the polarization of the electrodes. This results in a deterioration of the EMF (i.e. voltage) due to the formation of a double layer at the surface of the electrodes. Negative ions tend to be attracted by the positive electrode and the positive ions are attracted by the negative electrode. If there is no chemical reaction at the electrodes and/or no mixing, the voltage will rapidly go to zero.
even if you invert the poles on your electrodes rapidly to avoid the accumulation of charges, the net voltage would still be zero.
Harness enough power from an old-growth forest to power an electric chainsaw for use in harvesting said forest.
Easy enough.
http://www.imdb.com/title/tt0125439/quotes
I think I may have discovered evidence of cold fusion in trees … should I tell anyone?
I thought that we already were using electric plants. 🙂
But we’re using electric plants which feed electric plants.
Just for comparison, California alone consumes an average of about 30,000 MW. That is 30 billion Watts. That represents somewhere around 2 percent of the worldwide electrical energy. And on a high-demand day California consumes more than 50 billion Watts.
Paraphrasing a line from the movie Jaws: We’re going to need a lot of trees. (We’re going to need a bigger boat. — from Jaws)
But wait…how much energy is required to fabricate the nails that will be used for electrodes? Then, how much energy is required to hammer the nails into the trees? This could be a net negative energy producer real quick.
Electricity from trees is nothing new. The so-called “internet rumor” came from John Bedini who discussed Nathan Stubblefield’s experiments from over 100 years ago. John Bedini talked about the battery tree on several radio shows over the past ten years, or so. It is odd that nobody is giving credit to the actual discoverer, but it does explain the “peer reviewed paper” qualification in the story. What is so special about being the first to get peer review? I thought the original discoverer was supposed to get at least some credit.
Ron de Haan (07:29:41) :
What happens when lighting strikes?
Well, you’re gonna need a new voltmeter, new nails, and maybe a new researcher…
But on the bright side, it will be really bright!
Fred Harwood (11:55:44) : Tesla, IIRC, demonstrated electrical power flows between earth and air, varying with altitude, among other things. Commercial amounts of power have yet to be extracted.
But you can extract enough to play. It’s about 100 V / Meter but low amps.
http://en.wikipedia.org/wiki/Atmospheric_electricity
Has:
In July of 1750, Franklin hypothesized that electricity could be taken from clouds via a tall metal aerial with a sharp point. Before Franklin could carry his experiment, in 1752 Thomas-François Dalibard erected a 40-foot (12 m) iron rod at Marly-la-Ville, near Paris, drawing sparks from a passing cloud.[6] With ground-insulated aerials, an experimenter could bring a grounded lead with an insulated wax handle close to the aerial, and observe a spark discharge from the aerial to the grounding wire. In May of 1752, Thomas François d’Alibard affirmed that Franklin’s theory was correct.
http://en.wikipedia.org/wiki/Sky_voltage
This one even mentions Global Warming. No, really:
http://spacescience.spaceref.com/newhome/headlines/essd15jun99_1.htm
And this one leaves me unsure if I ought to laugh or cry… An old plan to collect electricity using balloons … covered in pins…
The strange thing is, I think it would likely work.
@rbateman
Glad I could help put a little ‘spark’ in your day 😉
Oops! The Missing Link:
http://www.rexresearch.com/plauson/plauson.htm
the pin covered balloon one…
A Lovell (14:27:31) :
Ric Werme 07:08:59
So, if plants are found to be sentient beings, what will the vegetarians eat?
Well… there are already folks like that in existence. Some only eat fruits and seeds. Some will only eat plants once they have “dried up” (i.e. naturally died). I haven’t had the heart to explain to them that a dried up seed is still alive, just dormant…
I once had a conversation with a person about ‘what can be eaten without killing something’. The only thing I could come up with then was an unfertilized egg, being one large cell without a viable nucleus … then I realized that eating it would kill the bacteria living on the outside of the shell 😉 Said person was not as amused as I was 😎
There is a sub-category of vegetarian that is a “carbotarian” and focuses on high carbohydrate foods. Some accept honey and bee pollen.
There is also the group that only eats raw food… and the folks that only eat parts of the plant that can be removed without killing the plant (so leaves are OK – spinach, lettuce, Kale as long as harvested one at a time from the plant…)
If you ever start hanging out with vegetarians, you rapidly learn that there are a dozen or three different kinds… Everybody is a quirky edge case.
Oh, and some will eat “stems” if the roots can regenerate the plant, so they will eat green onion TOPS harvested leaving the roots to re-grow, but not bulb onions…
FWIW, if you keep every living seed alive from some plants, like Parsnips or Quinoa, or even worse, amaranth, you will cover the whole planet in those plants within just a few years… (Amaranth, for example, makes a plant about 5 foot tall that makes a cup to a liter of seeds per plant. And the individual seeds are about the size of a period made with an ink pen… Take about 4 or 5 orders of magnitude increase each year and you get a whole lot of plants in a hurry…) Unfortunately, I’ve known a lot of folks who did not follow the size argument that shows most of the seeds MUST die.
What would Treebeard think?
I had a short conversation yesterday with a guy who was rewiring a street lamp:
Me: “Not very big these volts, are they.”
He: “No. There are 415 of them in there.”
Me: “Wow. 415 in a little wire like that! What will they do next. A lot bigger than ohms though. I have a tiny thing with 10 million of them.” (etc.)
I wonder if he was the same electrical engineer! About the same level by the sound of it.
All things have to start somewhere. Who knows in X years this could be the start of a forest monitoring device.
However, the likely ends for such ‘peer reviewed’ article is it’s use as a political building block (purely because of the ‘peer reviewed’ status).When nothing comes of this it’ll be yet another argument that ‘big oil’ is blocking yet another renewable energy source.
I’m just wondering if the BlendTec “Will It Blend?” experiments are peer reviewed.
John M (17:47:09)
EM Smith (01.30.38)
Thanks so much for your great responses to my question. I’d forgotten that quote from Notting Hill, although I have met people like that. I will keep the seeds argument in mind if I have the misfortune to meet any more :)!
A lot of warmistas seem to be veggie/vegan/fruitarian types. I wonder what they think they’ll be eating if they get their way and we’re back to the stone age………
Just as I expected — he’s rediscovered the concentration cell. 5 minutes of googling came up with a Japanese paper:
Electrolyte-concentration Cell using Bruguiera Gymnorrhiza
published in Electrochemistry in 2004
Abstract;An electrolyte-concentration cell was fabricated and its power generating characteristics were evaluated for the first time using salt-tolerant plant Bruguira gymnorrhiza. This plant is known to grow in sea water and the chloride concentration in sap is lower than that in the saline surrounding the root. Plant tissue that separated the saline and the sap usually contains several ions like potassium and calcium, and was thought to show ionic conductivity. An electrolyte-concentration cell was, therefore, thought to be able to fabricate using the chloride ion concentration difference and the ionic conductivity. One of the two Ag/AgCl electrodes was inserted into the petiole of the plant, and the other among the vermiculites that supported the plant root. The vermiculites were soaked in a 400 mM NaCl solution. Two electrodes were connected to a galvanostat and the voltage was measured under a fixed current (20 nA) mode. The voltage gradually decreased with time from 260 mV to ca. 175 mV in two weeks. A periodical change in the voltage was observed. The internal resistance of the system was estimated to be 1.78 G.OMEGA.. (author abst.)
My read of the internal resistance of the “battery” is 1.78 gigaohms which does limit somewhat the circuitry one can power with it.
I got better results from a gravity battery. Always positive on top and negative on the bottom. A wild ass idea one boreing afternoon. As high as .500 milivolts ( must have been a mistake) at .003-5 miliamps. Some day ( when I’m resting) I should do some real tests.
actually 500 millivolts @ .005 milliamps sorry, old eyes, late at nite.
E.M.Smith (01:02:04) :
Wow – what an incredible web site. It would take a lifetime to wade through it all, document why some of the perpetual motion systems (a lot I haven’t seen before) process energy, sort out the stuff that should be discarded, and find the gems that deserve more attention.
Relevant to this discussion is http://www.rexresearch.com/squier/squier.htm on using trees as radio antennas (in 1919) and more recently (2005):
Hmm. Aluminum & copper – a galvanic battery. One down. (Maybe after testing with non-reactive electrodes.)