BMW may be about to embrace electrification in a very big way, if the latest reports are to be believed.
According to British magazine Autocar, BMW may equip the majority of its road cars with petrol/electric and diesel-electric powertrains, with the hybrid powerplants designed to run primarily on electric power under most conditions.
With the i3, all propulsion comes from an electric motor connected to the rear wheels. An optional range extender model adds a two-cylinder scooter engine to drive a generator to charge the lithium-ion battery, but doesn't send drive to the wheels..
The i8 is a more conventional hybrid with the combustion engine being both a generator and drive motor, but like the i3 it features a plug-in charging capability.
The new strategy will be more like the i8's approach, will reportedly apply to BMW's larger models and is targeted at reducing the brand's fleet-average CO2 emissions to around 95g/km by 2021.
With BMWs from the 3 Series and larger being responsible for 75 percent of BMW's fleet-wide emissions, it makes sense to hybridise them first.
The proposed system will supposedly see an electric motor/combustion engine turning the front wheels and an electric motor on the rear axle, with a lithium-ion battery pack mounted between them in the centre tunnel.
While the combustion engine will be capable of driving the front wheels, it should only come into play for roughly ten percent of every journey.
To compensate for the extra weight of motors and battery packs, BMW's future models will also see greater use of aluminium alloy construction and carbon fibre components. Engines should also become lighter and less complex at the same time- thus making them cheaper to produce.
All up, the report states that a car the size of the 3 Series would be around 100kg lighter than the present-day model.
The architecture and powertrain is also expected to be scalable, with an unnamed BMW source saying it could accommodate anything from a "3-series to a V12 Rolls-Royce".
Such high levels of scalability - the system would also be capable of equipping BMW's popular range of SUVs - would help reduce the price impact of such technology to a negligible level.
There's been no confirmation of any such plan from BMW themselves, and we must stress the above is strictly rumour for now. However, if it all turns out to be true we may expect to see the first examples of this tech roll out in 2018, when the next-generation 3 Series is expected to make its debut.
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