Piezoelectric Public Works Possibilities

An attempt to use the vibrations of vehicles on California’s streets and highways to generate electricity was among the legislation vetoed by Gov. Jerry Brown.

The bill would have ordered the California Energy Commission to pay for research on piezoelectric technology to determine if it could efficiently create power for call boxes, roadside lights and other electrical needs.

Certain materials like crystals and ceramics generate an electrical charge when they’re pressed or squeezed. That’s piezoelectricity. It’s the foundation of sonar – thin quartz crystals between metal plates send out a sound and measure distance by the time it takes the echo to bounce back. Closer to home, piezoelectricity makes the push-button ignite a propane barbeque.

A criticism has been that piezoelectricity is low on efficiency.

The goal of the bill – AB 306 by Assemblyman Mike Gatto, a Burbank Democrat – was to have the energy commission explore the use of underground piezoelectricity sensors to convert the vibrations caused by vehicles on roadways to energy.

“The Legislature by requiring the funding of this specific technology is bypassing the independent and careful process of the energy commission. I don’t think that’s a good idea,” Brown said in his veto message.

Piezoelectricity is already being studied by the energy commission. The commission reports spending about $400,000 over the past eight years on piezoelectric research at the California Institute for Energy and the Environment at the University of California at Berkeley. A published summary of the results is expected during the fiscal year that begins July 1, 2012

Israel employs sensors under some of its roadways. According to Environmental Magazine, the dance floor at Temple, a nightclub in San Francisco, is being designed to cover some of the club’s electrical needs through piezoelectric sensors beneath it.

Lt. Gov. Gavin Newsom supported the measure. He attempted to pilot the use of piezoelectricity as mayor of San Francisco.