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Piezo Crystals Harness Sound To Generate Hydrogen
MikeChino writes "Scientists at the University of Wisconsin-Madison have discovered that a mix of zinc oxide crystals, water, and noise pollution can efficiently produce hydrogen without the need for a dirty catalyst like oil. To generate the clean hydrogen, researchers produced a new type of zinc oxide crystals that absorb vibrations when placed in water. The vibrations cause the crystals to develop areas with strong positive and negative charges — a reaction that rips the surrounding water molecules and releases hydrogen and oxygen. The mechanism, dubbed the piezoelectrochemical effect, converts 18% of energy from vibrations into hydrogen gas (compared to 10% from conventional piezoelectric materials), and since any vibration can produce the effect, the system could one day be used to generate power from anything that produces noise — cars whizzing by on the highway, crashing waves in the ocean, or planes landing at an airport."
I could be wrong, but I thought sound waves moving through air carried a surprisingly small amount of energy. When it comes with tangible vibrations, waves so strong they pulsed through the ground and other solids to reach you, the net effect might create significant amounts of energy, but just loud noises probably wouldn't give you much in the energy department, especially at 18% yield.
Compared to normal electrolysis of water?
Before you start throwing around the fud, maybe you should check a few pesky facts. Lets start with current cars. Pretty much 4 wheels a cabin, an engine and big ass tank of flammable liquid with a low ignition point and a high explosive rating due to vapors. It's fuel air mixture is also fairly wide. To compare, we have hydrogen gas... Which has a narrow fuel air mix, a high ignition point, and which is lighter than air. So now we imagine a freeway with a wall on either side. The wall is an aquarium with crystals and a piping system to extract the hydrogen into the grid. Now, your car, which is a finely tuned BOMB ruptures the wall, breaking the aquarium and the gas lines. What happens? The water pours out, probably retarding any fire your car started, and the hydrogen goes straight up and dissipates harmlessly. Most likely, you never had a fuel air mix capable of igniting the hydrogen.
Liquid fuel used in automobiles is about as volatile as anything gets (at least in public spaces). Ng, Hydrogen and other compressed gasses are considerably safer. They dissipate quickly, require fairly small windows for ignition, and most of them require significantly more spark to fire up in the first place.