Bentley will build an SUV. It won't look like this, but will look like this. And in 2017, it will be offered as a petrol-electric hybrid.That much you know, because we told you so last month. Today we can tell you a fraction more, because that petrol-electric hybrid powertrain is being previewed at the upcoming Beijing Motor Show in the form of the Mulsanne Hybrid Concept.There's no word on the specific technical details of the upcoming hybrid SUV, but this concept uses the firm's 6.75-litre V8 mated to an electric motor and battery system. Bentley claims the hybrid drive will offer up to 25 per cent more power and a 70 per cent reduction in CO2 emissions.Taking then, the power of the standard' Mulsanne V8 (505bhp), that means somewhere in the region of 630bhp and - if our TopGear maths are correct - an astonishing 118g/km of CO2 (if again, we take the Mulsanne's 393g/km as our starting figure). That's... incredible, frankly.No word on performance, but with more power on board, we're sure the Hybrid Mulsanne will be able to sprint to 100kph quicker than the standard car's 5.3s time.We are told however, that this drivetrain is capable of travelling up to 50km on electric power alone, which we assume will require a rather substantial battery. Still, eat that, Congestion Charge. The show car also gets copper accents around the exterior and inside the cabin to drill home the point that this car uses electricity.And it's an interesting point, too. Bentley chief Dr Wolfgang Schreiber reckons that by the end of the decade, '90 per cent of our production will be available as a plug-in hybrid', with this powertrain eventually being introduced across the model range. Woah.We'll know more once it hits the show floor in Beijing.