Can traffic generate electricity? © Getty Images

Can traffic generate electricity?

Replace hamster with car, replace wheel with road, connect to grid?

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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