BMW has launched its first hybrid models at the Frankfurt motor show — and one of them will be the world’s most powerful hybrid.

Badged ActiveHybrid X6 and ActiveHybrid 7, the two cars use V8 petrol engines, but the X6 features two electric motors while the 7-series has one.

See the high-res BMW X6 and 7-series hybrid picture gallery

The X6’s drivetrain will produce a combined 478bhp and 575lb ft, which makes it the most powerful hybrid in the world, according to BMW.

That’s enough to enable the car to reach 62mph in 5.6sec, just 0.2sec slower than the xDrive50i. BMW also claims combined fuel consumption of 28.5mpg, with CO2 emissions of 231g/km. The car can also run on electric power only at up to 37mph for 1.6 miles.

BMW has attempted to differentiate the ActiveHybrid X6 from a regular X6 with the addition of what it calls a powerdome on the bonnet — a bulge in the sheetmetal — and it comes in a new metallic blue available only on this model.

However, all this additional technology means the ActiveHybrid X6 weighs in at 2450kg, making it 185kg heavier than a standard V8 X6. Its maximum permissible vehicle weight is 3100kg.

The 7-series is less powerful, with 459bhp and 561lb ft, but faster, cleaner and more fuel efficient. It hits 62mph in 4.9sec, returns 29.1mpg and emits 219g/km of CO2. It’s not a full hybrid, though, and can’t run on the electric motor alone; it’s just a back-up for the V8.

The electric motor and its ancillaries are similar to those used in the Mercedes S400 hybrid — BMW and Daimler co-developed the tech — and it uses lithium ion batteries.

Like the S400, neither BMW will be available in the UK, due to the cost of re-engineering for right-hand drive and the limited appeal of vehicles with large petrol engines here. “Eighty-five per cent of X6s and 90 per cent of 7-series sold in the UK are diesel-powered,” said a BMW source. “And both hybrids are petrol-based, so they’re a niche within a niche.”

Dan Stevens

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