California is known for having some of the most congested freeways in America— millions of cars drive on those freeways everyday, and now there might be a way to harness energy from all of those tires.
The California Energy Commission (CEC) has approved a pilot program in which piezoelectric crystals will be installed on several freeways.
Piezoelectric crystal technology is the same technology that is found in Barbecue starters. They work by giving off an electrical discharge when they’re mechanically stressed, so such a technology can be inserted under roads so that when a vehicle drives over them electricity is produced. Multiply that by thousands of vehicles and it creates an electric current that can be harvested to feed the grid.
Research suggests that energy generated from piezoelectric crystals on a 10-mile stretch of freeway could provide power for the entire city of Burbank a population of roughly 100,000.
Piezoelectric based energy‐harvesting technology is already being used in other countries. Since 2009, all the displays in the East Japan Railway Company’s Tokyo station have been powered by people walking on the piezoelectric flooring. Italy has signed a contract that will install this technology in a portion of the Venice-to-Trieste Autostrada. Israel is already using this technology on some highways.
“I still get stopped on the street by people who ask what happened to the idea of using our roads to generate electricity,” said Mike Gatto, a Los Angeles assemblyman, in a press release announcing the program. “California is the car capital of the world and we recycle just about everything. So why not capture the energy from road vibrations and put it to good use?”
“If piezoelectric‐based technology has the potential to match the performance, reliability and costs of existing or emerging renewable energy sources, then it can potentially diversify California’s resource portfolio and ultimately increase grid reliability and reduce costs to ratepayers,” states a report prepared for the CEC in 2014 by international certification body and classification society.
This video provides an animated illustration of how they could generate electricity on roadways.
California Gov. Brown vetoed an assembly bill Gatto introduced in 2011 that would have launched two piezoelectric pilot programs in California, Gatto asked the CEC to study the technology, and Five years later, the CEC has agreed to fund pilot projects around the state.
If they are successful, perhaps other states will consider harvesting electricity from their busy roadways.