When I was on my company's R&D team, we were looking at possibly designing a car. One of our ideas was regenerative braking (nothing new, I admit). Basically, y

When I was on my company's R&D team, we were looking at possibly designing a car. One of our ideas was regenerative braking (nothing new, I admit). Basically, you can use several types of pump or motor as a generator when run in reverse. This allows you to collect that energy back into the system instead of wasting it all as heat. It also has the added benefit of turning the rotational kinetic energy into stored potential energy, thereby slowing down the vehicle. Our design still included disc brakes for safety, but would have used the regenerative braking most of the time.