When we think about faults, like the Loma Prieta or the San Andreas, we think of big earthquakes every fifty years, and between them is happy fun time.
This isn't the case - in reality, tremors occur all of the time along earthquake faults and their various subfaults.
Even the smallest of these tremors generates a large amount of energy - it would have to, to move big chunks of earth even a quarter of a millimeter.
So why not harness this to power the human population? It seems only fair - earthquake smashes building, but we steal its energy...yes...its glorious energy...
Place a grid or other layout of wire just below the ground in earthquake-prone areas. Place strong magnets on flexible poles above the grid. Even some of the slightest tremors would move the magnets, which generates a change in the magnetic field, which generates a charge in the wires, which could be fed into the local power grid or could be stored in batteries of some form.
Bonus feature: A bunch of swaying magnets on poles might be considered art.-- shapu, Feb 25 2005 I got your earthquake harnessing scheme right here! Harvest_20the_20Earthquake [bungston, Feb 25 2005] But a fraction of a millimetre of movement in the magnets won't generate much power. I agree that there is a massive amount of energy available when a fault moves, but I think it could be difficult to harvest a meaningful percentage of it.-- david_scothern, Feb 25 2005 I think the problem with this idea is that, as [david_s] rightly points out, most movements in an earthquake zone as so small as not to provide significant energy.
Conversely, when the fault really shifts, you may well realise energy using your method, if and only if, the mechanism survives the earthquake.
<aside> the richter scale is logarythmic - an earthquake richter 6.0 is 10 times stronger than a 5.0 and 100 times stronger than a 4.0. The earthquake that caused the Indian Ocean Tsunami was 9.0 ... more than a 100 times stronger than the richter 6.9 earthquake in San Francisco 1906. Scary.</aside>-- jonthegeologist, Feb 25 2005 How about a piezoelectric gizmo? I seem to remember that earthquakes often generate electrical energy anyway, through their piezoelectric effect on quartz-containing rocks. Something like this would be a better way to harvest energy from a high-force, low- distance effect.-- Basepair, Feb 26 2005 [bungston] already went Piezo. He even used the word "hut."-- shapu, Feb 26 2005 [basepair] it's the quartz crystal itself that has piezoelectric qualities so your idea would only work if the rock (definition : mineral mass) is made of pure quartz. Or in other words, pure quartzite or 100% mature sandstone - that's a very small segment of the range of rock types.-- jonthegeologist, Feb 26 2005 jon - presumably with a quartz- containing rock like granite, each individual quartz crystal develops a voltage across it? I guess the polarity depends on the crystal axis (??) Do you know if the electrical anomalies reported around earthquakes are real? I've read about them being used (through probes in the ground) to predict or monitor earthquakes (presumably with not much success), and I've heard that lightning discharges are sometimes associated with quakes, but I have no idea if this is sound or bogus.-- Basepair, Feb 26 2005 random, halfbakery