Recycled rubber PaveGen slabs are to be installed in the walkway between the London Olympic stadium and the Westfield Stratford City shopping mall, to generate energy to power half the exterior lighting needs by footfall alone. With 30 million customers expected at Europe's largest shopping centre in the first year that's a lot of feet generating a lot of energy.
The slabs work on the basis that each footstep depresses the tile by 5mm, generating a tiny amount of kinetic energy which is either used immediately to power a specially designed LED outdoor light or can be stored for up to 3 days when there is a temporary lull in foot traffic.
Currently a school in Kent has them in a corridor for testing, Bestival on the isle of Wight saw them in use for generating charging facilities for mobile phones and a number of clubs have them in place for dance floor lighting.