Best shape and location of a piezoelectric plant?

Question

Members of the electric bacteria (Shewanella) genus possess capabilities allowing the use of a variety of other electron acceptors for respiration. These include thiosulfate, sulfite, or elemental sulfur, as well as fumarate, arsenic, manganese, chromium, uranium, and iron.

Ever since finding out about this bacterium I’ve been constantly mulling over different electric life forms. The concept was cool but there are quite a few complications in order to make it work. And the common problem I’ve found besides storing electricity was that the creature would have no reliable source of energy, other than biting a power line which wouldn’t appear in nature. So what if I designed a plant that generates and stocks electricity? I could have made a photovoltaic plant, but photosynthesis already exists which makes it kind of pointless and less efficient to boot. Instead how about a plant that generates electricity when stressed?

The Piezoelectric Effect is the ability of certain materials to generate an electric charge in response to applied mechanical stress. There may not be a protein that can do this but it doesn’t matter as I can just hand-wave it. It’s not as if my character will dissect the plant to see what it’s made of right? Crap! He’s a scientist...

Which brings me to my query what would be the best shape/design for such a plant and where would it live to make the most out of this ability?

So far what I could think of was a dark environment so photosynthesis wouldn’t be the better option. Flexible trees that flutter in the wind or catch waves or currents underwater or even bushes that grow better when creatures brush through them.

Answer 1

Don't rule out photosynthesis. Different ways to generate energy don't necessarily have to be mutually exclusive.

The best place for such a plant to evolve would be somewhere which has frequent seismological activity. The perfect place would be Chile, because:

1. Chile never stops shaking. Just in the last 30 days, Chile was shaken by 6 quakes of magnitude 5.0 or above, 71 quakes between 4.0 and 5.0, 476 quakes between 3.0 and 4.0, and 659 quakes between 2.0 and 3.0. Going to Santiago or Valparaiso is a unique experience. If you stay for longer than three months, I think you are guaranteed to see some buildings dance. I don't recommend this for those with labyrinthitis.
2. It is a very mountainous place. Up the hardier mountains, plants have a hard time growing roots among the rocks. This makes photosynthesis harder to perform, so having an alternative form of energy generation would be great.

The best shape for a plant to absorb energy from vibrations would be something close to a drum (so probably a small, roundy cactus) or a trunk with fibrous twists. The vibration would be captured and transformed into energy by organelles inside cells - they can use DNA and contrary to your expectations, various proteins as well. The purpose of the drum shape or the fibers is to maximize the vibration absorption. Think of the plant as a musical instrument in reverse. With a drum or a string, you feed energy and you get vibration. But they can also work the other way around (such as in an electric guitar, which turns the string vibration into electric energy again, though usually not piezoelectrically). These shapes allow the plant as a whole to keep vibrating longer after a quake, so the organelles have more opportunity to extract energy from the shake.