Floor tiles generate electricity using the power of footsteps
A new sustainable energy technology has been created which generates electricity by harnessing the power of footsteps. Pavegen has created a floor tile that captures energy similar to a kinetic energy recovery system (KERS). When the floor tile is stepped on, it depresses by 1cm, the downward force drives a flywheel inside the tile which spins to generate kinetic energy through electromagnetic induction.

As Fitbit users like to point out, walking burns a lot of calories. But the energy you expend doing it ceases to be useful after your sneakers hit pavement. That's where Pavegen CEO and Founder Laurence Kemball-Cook saw room to create a new kind of sustainable energy technology. His company's Pavegen floor tiles generate electricity by harnessing the power of footsteps.

The tiles are a kind of kinetic energy recovery system. We've seen these before in race cars and buses---but where recovery systems in automobiles convert the kinetic energy normally lost in braking to electrical energy, Pavegen tiles are all about capturing the spring in your step. Tread on a tile and the surface depresses up to one centimeter (Kemball-Cook compares the sensation to walking in a children's play-area). The downward force drives an energy-storing flywheel inside the tile, which spins to convert kinetic energy into electrical energy through electromagnetic induction. It's like a generator---only instead of spinning a turbine with wind, water, or coal, it's spinning a flywheel with footsteps.

The beauty of these tiles is that they can conceivably go anywhere there's floorspace and foot traffic—think airport terminals, sidewalks, and playing fields. That idea has attracted support from companies as big as Shell and celebrities as diverse as Al Gore and Akon (yes, that Akon)—but backers were hard to come by when Kemball-Cook started out. He began developing the technology while studying design at Loughborough University, and developed the first prototype in all of 15 hours. "I just hacked it together. There was wood in it, and it was held together by duct tape. I went to 150 venture capitalists, and they all said no. The government said, 'It would never work, we can’t help you.'"

That was seven years ago. Pavegen tiles have since been used to help light soccer pitches in Brazil and Nigeria, a hallway in Heathrow Airport, and offices and shopping centers in London. And that was all with less-efficient technology. Earlier versions of tiles were rectangular, and only produced power when someone's foot fell in the center of a tile. The latest generation of Pavegen tile, V3, is triangular, which allows them to include a generator in each corner. That means the whole tile pivots toward a generator no matter where you step. The V3 generates 5 continuous watts of power as you walk across it---that's more than 200 times more efficient than Kemball-Cook's first prototype.

Granted, five watts isn’t a ton, and not everyone is convinced that the world will ever run on Pavegen. For the 2013 Paris Marathon, Pavegen laid down a 25-meter strip of the last generation of tiles, and they ended up generating 4.7 kilowatt hours of energy---enough to keep an LED bulb burning for over a month, but nowhere near enough to power your home. "The very basic physics of it is pressure times the deformation of the material," says David Horsley, a mechanical and aerospace engineer at UC Davis. "You're not going to get very much for a step, considering you can get 100 watts from a square meter of solar paneling. But for small wearable electronics like watches, or maybe even your phone, this kind of energy harvesting makes sense."

So it's not going to put big oil out of business, and you may need to take a lot of steps to make them worth it. Good thing they're durable as hell. "The floor is one of the harshest environments known to man," Kemball-Cook says. "You have to be able to withstand environment challenges, water, vandalism. You need good test equipment. We have a footfall rig with four pneumatic drivers that's being going nonstop for four years, running analytics and just trying to destroy the product."