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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."
But can it produce enough electricity to power a small radio that plays the music used to create the vibrations necessary to produce the electricity?
No.
Sincerely yours,
The Second Law of Thermodynamics
Hey mate, spare a sig?
Your absolutely right, you're just getting bogged down with the pedantic ramblings of the Slashdot crowd.
They're joking and arguing about a perpetual motion machine, nothing to do with reality...
My question is this "If you're producing Hydrogen... aren't you also producing Oxygen at the very same time?" So here you are creating a combustible gas mixture in a stiochiometrically perfect balance to go BOOM-POW!!! The gases are created together, you can't easily separate them. You need to pump this straight into a combustion chamber or fuel cell, because it's ready, willing, and able to off the instant it's created. It cannot be transported anywhere.
The air to water transition is a huge impedance change. so most sound will be reflected not transmitted into the water. Second Since they are talking about 18% of the absorbed energy being converted and not 18% of the incident energy, even once it gets into the water most of the incident energy is probably reflected or absorbed in the water itself.
Unless they have already taken these into account it seems like the conversion rate of air acoustic energy to hydrogen energy must be in the fraction of a percent. Even so free is free, and some forms of vibration like car vibrations might be coupled in without going through the air.
Some drink at the fountain of knowledge. Others just gargle.
I don't think so.
Flammability Concentration Limits
Hydrogen 4% to 75%
Gasoline 1.4% to 7.6%
The auto-ignition temperature is indeed higher for hydrogen, 500 Celsius compared to 280 for gasoline. I had not known that.
a,e,i,o,u and sometimes w and y (at be if of up cwm by)
What do you think happens to the oxygen? It's in the same mixture.
You throw away the Oxygen as it is created. When the hydrogen is combusted eventually, oxygen will be taken from the air for the purpose.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"