We already know that BMW isn't interested in making any hybrid gas/electric vehicles unless they can find a way to make the system more efficient than their most efficient diesels (click here for more from AutoblogGreen). But, that does not mean that some of the technology pioneered in hybrid vehicles can't find a place in the BMW model range.
Take for instance regenerative braking. While your standard hybrid is capable of recapturing energy normally wasted in braking with their electric motor(s), the same technology can be used in a more mainstream application by aiding the alternator in energy production. The BMW 5-Series and 1-Series have already used this type of system with good effect, so it comes as no surprise that BMW would implement it in their best-selling 3 Series as well.
The system is capable of coupling and decoupling the alternator from the engine, which has the dual benefits of slowing down the vehicle when engaged and freeing up more engine power for the wheels when disconnected. It's nice to see that performance and fuel-economy can cohabitate under the same hood.
[Source: Motor Authority]