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Tapping Trees for Electricity?
dr_agonfly writes "Despite many skeptics, a Massachusetts company is getting investor interest in developing a process to tap electric power from trees. MagCap is looking to boost the current power from just under 2 volts to a more useful 12 volts with investor funding." From the article: "Jim Manwell, director of the University of Massachusetts Amherst's Renewable Energy Resource Laboratory, questioned the potential of MagCap's plans. 'I'm wildly skeptical,' he said. 'I would need to see proof before I believed it. It strikes me as pretty questionable for a number of reasons.'"
How about something more useful? Like wattage?
MagCap is looking to boost the current power from just under 2 volts to a more useful 12 volts
Neither current nor power is measured in volts. If they can't get that right...
You're an immobile computer, remember?
One big difference is that the lemon is dead and slowly rotting, needing replacement. The tree is living, thus the only thing that needs replacing (assuming that the drainage doesn't destroy the tree) is the anode and the cathode. But we use electricity to make aluminimum don't we? I'll bet this comes out to be energy negative in the long run.
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
It doesn't sound too different from the old lemon battery experiment. Sure, he might be able to generate voltage, but the question is...Where are the AMPS? If he has 12V at .005 milliamps, this tree electricity won't be useful to anyone. I hope not too many investors are buying this guy's line...
-R
Nothing to see here...
Oh, the energy comes from somewhere indeed. There is an aluminum spike and a copper spike inserted into a tree. A tree has water with several dissolved compounds (including acids and salts) flowing through it. The tree's sap acts as an electrolyte, while the spikes are the anode and cathode in a simple aluminum/copper battery, similar to this gradeschool science experiemnt. The spikes will be consumed in the reaction, thus the tree is not generating any power at all. The fluctiations in voltage would be related to a changing internal resistance within the tree. Considering the amount of energy it takes to make aluminum, this fits under the "nothing to see here" category.
I'll never make that mistake again, reading the experts' opinions. - Feynman
Oh yeah, and considering the electric potential of reducing copper is .34v, while the electric potential of oxidizing aluminum is -1.66v this working out to .34 - (-1.66) = 2volts, it seems kinda suspicious that the tree "generates" up to two volts of electricity.
I'll never make that mistake again, reading the experts' opinions. - Feynman
The article says there is voltage, but nothing on current. How much current is drawn across 2V? Power = current * voltage. You could have 1000 V, but if the current is about a nano-amp, you won't have enough to run a radio.
It's funny to see 300 people point out that this guy has re-invented the potato/lemon battery, and at the tail end of the story someone tries defending the process, by quoting the FAQ:
.. well, all I see is talk about voltage, but we'll leave the advanced (ie: grade 11) physics out of this for now. We can safely stick to elementary school science for this. Go make a potato battery using the smallest potato you can find, and copper and aluminum electrodes. Now go make one using the biggest potato you can find. Notice that the voltage you can get from that is exactly the same!
Q: Is the voltage potential between an electrode inserted in the tree and one grounded both having different electro-potential characteristics due to electro-chemical reactions e.g. Galvanic batteries?
A: In a Galvanic reaction there is metal to metal contact. Henceforth the word "galvanized". Validation and voltage measurement does not involve metal to metal contact.
See, um, I'm no physicist, but I do know that in a galvanic cell, the metals most definitely do NOT touch each other. There is no metal-to-metal contact. None. The metal electrodes only interact through an electrolytic medium which carries ions between the two of them.
Just for fun, let's look at the rest of this answer:
In addition, a chemical reaction requires a very elevated or very low PH level in order to create this alkaline or acidic condition.
No, chemical reactions can take place at literally any pH. Try again.
A chemical reaction requires hours if not days to manifest.
Try telling that to someone who works with high explosives. Or, if you don't believe me, go to your kitchen and add some vinegar to some baking soda. It won't take hours to react, but see for yourself if you're unsure.
Anyway, the fact that the size of the trees has no effect on the amount of power
Dude, you've been hoodwinked. The FAQ is entirely, completely, 100% wrong on the most basic fact of how batteries, and for that matter, chemisty works.
Mods, you've been had as well.
Endless arguments over trivial contradictions in books written by ignorant savages to explain thunder in the dark.