The system draws on current plug-in technologies used in the i3 and i8 models.
The 3 Series PHEV will feature a TwinPower turbocharged four-cylinder petrol engine, matched with an electric motor and an eight-speed automatic transmission.
On battery power alone, the 3 Series PHEV will offer a range of around 35km with a top speed of 120km/h.
Combined power and torque is listed as 180kW and 400Nm, with an overall fuel figure of just 2 l/100km and CO2 emissions of 50g/km.
BMW has also unveiled a 5 Series GT PHEV prototype to further demonstrate its new system, with a focus on maximising the input from the electric engine.
The German carmaker plans to improve its battery-powered engines to offer around two thirds of total power output in future models, while also boosting overall fuel consumption.
The 5 Series GT example shows the potential of such a plan with an impressive 500kW and 1017Nm in combined power, using just a 2.0 litre TwinPower turbocharged four-cylinder petrol engine and a pair of electric motors; one each for the front and rear axles.
A new 20kWh battery pack has been developed for the prototype which offers around 100km of electric-only range, and BMW’s confidence in the new system has prompted a much smaller fuel tank - 30 litres instead of 70.
While the petrol engine will usually act as a generator, it can be called upon to provide additional power to the front wheels under maximum acceleration.
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