Oh, batteries. Can’t live with ‘em, can’t live without ‘em. Then I saw some news on this field. Potatoes May Power The Batteries Of The Future article tells about a potato powered battery. It promises to be simple, sustainable, robust device can potentially provide an immediate inexpensive solution to electricity needs in parts of the world lacking electrical infrastructure. Researchers at the Hebrew University claimed that the boiled potato or other similarly treated vegetables could provide an immediate, environmental friendly and inexpensive solution to many of the low power energy needs in areas of the world lacking access to electrical infrastructure. The ability to produce and utilize low power electricity was demonstrated by LEDs powered by treated potato batteries.
Does this sound too good to be true? The fact is that is too good to be true. And this is not a true green power source. It is a fact that you can use potatoes and metal electrodes to make a working battery. The problem here is that the energy extracted from this battery actually doesn’t come from the potatoes, but from the corrosion of the electrodes. Yes, you can get energy even from an “Earth Battery”, but no, it ain’t free. If you replace the potato or soil with zinc chloride or acid you get a better working battery. These substances have better electrolytic properties.
So the original news article misses the point about where the power in batteries actually comes from, which is the difference in electric potential between the two metals used as electrodes. What you get is most propably a small a fraction of the energy that was necessary to produce the metal from ore. Not exactly an efficient way to store power, and a terribly stupid way to use expensive metals! And in addition to that the potato used on this experiement is just waste contaminated with metal.
So to get green energy would be better to use commercial rechargeable batteries and use actual real renewable energy such as hydro or wind to recharge them.