Wikipedia
Pavegen Systems is a technology company that has developed paving slabs to convert energy from people's footsteps into electrical power.
A typical tile is made of recycled polymer, with the top surface made from recycled truck tires. Power is generated when a footfall compresses the slab by about . The exact technology is a secret, but PaveGen officials have said it involves the piezoelectric effect and induction by copper coils and magnets. Pavegen says each footfall generates up to 7 watts at 12 volts DC, enough to run an LED street lamp for 30 seconds. The technology was developed by Pavegen founder Laurence Kemball-Cook.
Among other installations, the slabs have been laid at London's West Ham Underground station for the 2012 Olympic Games. In April 2013, a demonstration installation harvested energy from the runners in the Paris Marathon. PaveGen has also put these tiles on a public soccer field in Rio de Janeiro to allow play after sunset and spark an interest for science.
A study of a central building at Macquarie University in Sydney, Australia, suggested that if pavers covered the 3.1% of the floor that sees the most foot traffic, it would generate an estimated 1.1 megawatt-hour per year, about 0.5% of the building's energy needs.