Can traffic generate electricity?

It certainly can. Not only have there been proposals to use America’s highways as a source of solar power, but you can harvest the mechanical energy in vibrations caused by cars and lorries. The basic proposal from Israeli company Innowattech is quite simple: when you’re laying a new road, you put down a layer of piezoelectric crystals under the asphalt.

These have a special property: they convert mechanical energy into an electric voltage as they’re distorted by passing traffic. Assuming 600 vehicles pass by in an hour, the company claims it can produce a current of 100kWh from a 1km stretch of road, or enough to power 40 homes. Innowattech is currently trialling the system on a 30m stretch of road outside Tel Aviv.

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