BMW is well practised in the art of electric car technology.
The baby i3 town car has been a runaway success and the i8 coupe has proved itself well capable of mixing it in the supercar league.
In their different ways both the i3 and i8 are stand-out, extrovert models with niche rather than mass appeal.
But by adaping its skills and knowledge to a mainstream saloon like the 3-Series the German marque is appealing to a wider audience that likes its cars to look conservative despite packing in cutting edge technology beneath the surface.
The 330e is one of a new breed of plug-in hybrids which probably make most sense to company car users who can at the moment take advantage of tax laws.
It is powered by a 2.0-litre turbo petrol four-cylinder engine and an electric motor, together pushing out 249bhp.
Anyone expecting lack lustre performance because of the car's mile-stretching economy is in for a pleasant surprise because the 330e is has hairy-chested acceleration and rapid mid-range urge.
It disposes of the 62mph rush in just over six seconds and is ultimately good for 140mph.
On the green side of life, it emits just 44g/km of CO2 which means zero tax and no congestion charge if you are venturing into the capital. This corresponds to 148.7mpg combined.
With a full charge, it will travel 25 miles in electric mode before the petrol engine gets involved so drivers who regularly do short trips can charge-up - which takes about three hours - between journeys and make the most of the technology.
Without the aid of the electric motor, fuel consumption sinks to more normal levels. My average was around 37mpg during some swift motorway and A-road running.
Not much gives away the 330e's electric secret. A couple of small eDrive badges and a filler panel on the front wing to carry out the charging are the main clues. Inside there's an eDrive button near the gear lever and a power gauge on the dash.
The only obvious penalty to hybrid ownership is a smaller rear boot. The size is reduced from 480 litres to 370 litres to store the lithium cell batteries.
When you start the 330e and set off from rest there's not so much as a murmur from the engine, accelerate away and the combustion unit joins in proceedings but travel remains quiet and refined.
Handling isn't quite as deft and athletic as either the pure petrol 320 or its diesel sibling because of the extra weight of the batteries, nevertheless it remains a pleasant drive with light progressive steering and strong roadholding. The eight-speed automatic gearbox is slick and harmonises well with the twin power units.
Technology aside, the rest of the car is pure 3-Series which means comfortable and spacious transport with BMW's usual high standard of finish and plenty of kit including leather upholstery and sat-nav.