The concept of re-generative braking is not new; gasoline/electric hybrids have been using the concept for some time to turn deceleration of mass into electron storage. But a team from the Institute of Engineering and Design at Brunel University in west London claim to have found a clever way to take advantage of the traditional internal combustion engine under deceleration (i.e., engine braking) so that it becomes an air pump; the compressed air is stored in a tank and used later for supercharging or perhaps even driving the pistons themselves.
Internal combustion engines are, in essence, air pumps. They suck air through an intake manifold and push it back out of the exhaust system, with combustion occurring along the way. Today's electronic engine management systems actually turn off fuel injectors under deceleration at zero throttle, at which point the engine is simply pumping air in and out of its cylinders. So why not harvest that compressed air and put it to good use?
The London team claim that most of today's engines would require only small, inexpensive changes to become air hybrids. Nonetheless, Professor Hua Zhao hails the development as a "major breakthrough" while admitting it must first be tested with automobile manufacturers for viability.
Not known is how much energy savings this new technology would yield. But if it does prove to be a cheap retrofit on most existing vehicles, the sum of its impact on global energy consumption could be enormous even with incremental increases in mpg.
[source: Motor Authority]