The truth is, people like to help but don't want to go out of their way to do so. That is what makes this idea from Pavegen so ingenious. Specially designed paving slabs are compressed as passers-by walk on top of them. The kinetic energy is stored up under the slab for later use. If the idea sounds vaguely familiar, it is probably because Sainbury's implemented a similar system in its Gloucester eco-store last year, where cars entering its car park drive over compressible plates, generating kinetic energy. The Pavegen scheme has already been trialled in East London and there are now plans to roll it out on a wider scale. Great idea, and something we are likely to see a lot more of on our pavements, car park floors and public stairwells soon.