Pavegen makes a tile from recycled polymer that converts footsteps into electricity. Laurence Kemball-Cook, founder and CEO of Pavegen Systems, says each time a person steps on a Pavegen tile, 7 joules of electrical energy are generated. Put enough of them down and get enough people to walk on them and you could create enough electricity to charge the battery in an electric car.
It just so happens that a Tesla Model S is an electric car and there are lots of people walking around in London. So Pavegen put down some of its tiles on a busy sidewalk and hooked them up to a Model S parked nearby.
According to Pavegen, “The system works and the Pavegen tiles were used to charge the vehicle. However, several hundred thousand steps are required to allow the vehicle to drive for 20 minutes on London’s Streets. If the footsteps were used from one of London’s busiest shopping location — Oxford Street — enough energy would be generated from a day of people walking to drive a car 953 miles. All the way from London to Barcelona and further!”
The folks at Teslarati are skeptical, however. “If it is 7 joules per step, that’s ~150,000 steps per mile (300 Wh = 1,080,000 joules). To fully charge an 85 kWh pack is 306,000,000 joules, or 43,714,285 steps @ 7 joules per step,” says Jason Hughes in a comment. Pavegen’s claims may be somewhat optimistic, but the idea of generating electricity from footsteps is still and intriguing notion.