We've seen the concept for roadways that generate power through either electricity or hydraulics, but it turns out there's actually at least one pace in the world where something similar is already happening. At the Sainsbury's supermarket in Gloucester, UK, a series of plates are mounted so that cars drive over them, pushing them downward and creating a rocking motion that's harnessed and used to turn a series of generators. Apparently, the 30kWh of power generated from the market's parking lot is sufficient to power the store's checkouts.
Assuming that these energy-generating plates aren't set up in a way that impedes the vehicles or requires additional fuel to pass over, this could potentially be an excellent way to control speed and generate electricity. Other eco-friendly practices used by this supermarket include the harvesting of rain water to flush toilets, floor-to-ceiling windows for natural light and solar-powered hot water heaters.
[Source: Daily Mail via Engadget]