Awhile ago I had seen a special on TV about a new way to conserve energy on highways, then I found <a href="http://www.alternative-energy-news.info/harnessing-power-highways/">this</a>.
It got me wondering what else could be done to conserve energy on our roads and highways. And although I have the idea, I am not sure how it could be done. Anyway, essentially there is a lot of energy lost when breaking down a large hill with any vehicle (although hybrids take advantage of this), and I was thinking that instead of braking down the hill and wearing down your brakes, there could be some kind of mechanism that slows the vehicle down to the speed limit and storing energy to power street lights or traffic lights. It would have to be able to be disengaged in case of emergencies and require no alterations to existing vehicles.
Is this possible? Any engineers willing to give some ideas and maybe try to put this to market?