How very BMW. The new ActiveHybrid 7 – Munich's name for its petrol-electric hybrid 7-series – is very much lodged at the top of the Seven family tree. Not for BMW to launch a sackcloth and sandals 7-series hybrid; this one sports a 4.4-litre V8, not one but two turbochargers and a 0-60mph sprint claim to worry many Porsches.
We lost count of the number of times BM execs stood up at the press conference and talked about 'driving pleasure' and 'performance'. This paints a clear backdrop to the ActiveHybrid 7's intent. Yes, CO2 and economy are better by nearly a fifth over the regular 750i donor, but they're hardly going to win you honorary membership of Greenpeace at 219g/km and 30.1mpg.
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So the BMW ActiveHybrid 7 is dirtier than a 730d or 740d?
Err, yes. But a diesel 7-series wouldn't see which way the hybrid Seven went in a drag race. Thanks to a compact electric motor built into the ZF eight-speed auto transmission, the ActiveHybrid 7 is relentlessly torquey and feels every second as fast as its sub-5.0 second sprint credentials suggest.
The electric motor is rated at 15kW or 19bhp – relatively small fry in the new world order of battery cars. But this is a mild hybrid, don't forget. Unlike the fully hybridised X6 ActiveHybrid, the 7-series isn't required to lug its substantial 2120kg girth on electric motion alone. It's more about tuning the drivetrain for ballistic thrust while still giving a nod to those demanding green emissions.
And why exactly is the ActiveHybrid 7 clean?
The engineers have tuned this car to shift up into top – eighth gear – at the earliest possible opportunity. You can barely hear the V8 most of the time until you acquaint pedal with bulkhead. The electronics then feed in battery power to create a tsunami of 516lb ft all the way from 2000-4500rpm.
Boy do you feel this on the road. There you are surfing along on a surfeit of torque, wafting past slower-moving traffic in refined peace. Kickdown and you're thrust back into your comfy 7-series seats in shocked awe. It's epically fast. My only gripe is that you never feel the full hybrid 'halo' effect of silent motion – a shortcoming shared by any mild hybrid.
At least the petrol engine cuts out at a standstill, saving petrol and allowing you a smug glow as you sit in saintly silence at traffic lights.
It sounds like a complex bit of kit. How has BMW packaged the hybrid gubbins?
The ActiveHybrid 7 is nowhere near as complex as its X6 sister. The SUV is a full hybrid and uses a very different set-up designed around two, not one, electric motors, four-wheel drive and the ability to drive on electric power for a couple of miles.
In the hybrid 7-series there's a new power control system under the bonnet to shuffle power between battery and internal combustion engine. Then there's the compact, 25kg electric motor housed in the auto transmission assembly. And finally there's the lithium ion battery, which sits in the far left corner of the boot, robbing the cargo bay of 40 litres.
The switchover between petrol and electric operation is impressively seamless. We noticed no electrical confusion or jerkiness in the drivetrain, apart from under braking. BMW claims pedal feel is unaffected, but we – and other reviewers – felt inconsistent braking response, as the combined effect of regenerative braking topping up the battery, conventional hydraulic braking retardation and the ZF eight-speeder changing down made it hard to brake smoothly without modulating pedal pressure ad infinitum.
Any other glitches on the ActiveHybrid 7?
Not many really. Jerky braking aside, the system works really well. The engine cuts out at standstill and restarts quickly enough not to raise your heartbeat. If you really step on it for a rapid getaway you notice a momentary pause, but it'll be fine for its intended limo usage. If you wiggle the steering wheel when stationary, the engine kicks in instantly to provide power assistance.
BMW has introduced a new electrically operated climate control system for this car, and it's claimed to provide cooling or heating for half an hour without the engine switched on. You can even operate it by remote control to warm your car up in winter as you munch your corn flakes and toast.
Elsewhere, it's the usual 7-series package: one of the nimblest big luxury car chassis on offer today; beautiful build quality; a modern, minimalist and gently divisive design ethic; a cavernous and pampering cabin; and so much technology that you'll wonder if it's all strictly necessary.
It's small surprise the ActiveHybrid 7 won't be sold in the UK. It's devilishly expensive, knocking on the door of £100,000, and the emissions and economy just can't live with BMW's very good inhouse diesels. A small degree of re-engineering would be required under the bonnet to make right-hand drive possible and BMW correctly worries it wouldn't see a return on that investment.
But as a range-topping proposition aimed more at petrol-dependent markets, such as the USA, Russia, Canada and the Middle East, this is like a 750i+. Performance is devastating, the eco credentials impressive when you consider that thrust – and it's labelled with 'hybrid' badges and kick plates at every which opportunity. And that message to your colleagues, clients and staff will be priceless to many keen to adapt their profligacy to the zeitgeist.