First drive tests the range of the 102EX and the nerves of Rolls-Royce

Ben Oliver sets off on a 180km loop around Lake Geneva to test the range of the one-off electric Phantom, accompanied by a very anxious entourage.

Due to the refined nature of the petrol-powered Rolls-Royce, the contrast with the electric version isn't as great as it is in other electrified cars. Courtesy Rolls-Royce

Just a few weeks ago, this car was the main attraction of the Geneva Motor Show stand, engulfed by the rolling media tornado that hovers around each new show star as it's unveiled: cameramen and photographers jostling, microphones thrust at the CEO who adjusts his tie and introduces arguably the most extraordinary electric car ever produced.

And now it's parked at the back of my hotel in Lausanne, Switzerland, looking not unlike the "ordinary" Rolls-Royce Phantoms you see with reasonable regularity on the roads around Lake Geneva. But the 102EX, also known as the Phantom Experimental Electric, is far from ordinary. Rolls-Royce has sent no fewer than three senior engineers - including the head of the project - two PR handlers and two chase cars to look after it. And they all look nervous. Not just because 102EX is a £2 million (Dh12 million) one-off that has a year of testing and press drives and customer events and other motor shows ahead of it, or for the fact that nobody outside Rolls-Royce has yet driven it. It's what I'm planning to do with their car that's causing them anguish.

When Rolls-Royce's senior executives first told me they were building an electric Phantom, we agreed that trying to drive it around Lake Geneva on a single charge would be a great first test. But their engineers got cold feet - the Rolls has a theoretical range of about 200km, and it's 180km around Lake Geneva. They liked the idea of finding out exactly how far their car would drive in real-world use, but they worried that the spare few kilometres just weren't enough to allow for the traffic we'd meet on the lakeside road and through the centres of Geneva and Lausanne. Standing still isn't a problem for an electric car. Constantly accelerating nearly three tonnes of Rolls-Royce and occupants from a standstill is.

I started to get phone calls asking if I'd consider calling the whole thing off; they didn't want a concept car that had just headlined the Geneva Motor Show getting beached ignominiously in a grey Swiss lay-by. But it was too good an idea to abandon. So I agreed to drive sensibly and not to photograph the Phantom if it had to be dragged onto the back of a truck.

It's worth pausing to examine why Rolls-Royce is building an electric car. This is not, the firm is very keen to stress, a "green" concept. This is not about environmental sustainability, it's about the sustainability of Rolls-Royce as a business. Its customers don't ask it for more environmentally acceptable cars. It's not that they don't care. If they want a Tesla or a Leaf or a Prius they'll just buy one; they don't look to Rolls-Royce for green solutions.

But Rolls-Royce knows that one day the oil will run out, and it needs to be ready with an alternative to petrol V12s that its customers find acceptable. You'd have thought that near-silent, vibration-free electric motors with huge, instant torque would be ideal. But a Rolls is more than a luxury good; it's meant to be a supreme piece of engineering, too, and the firm is remarkably candid about being unsure how important an actual engine is to its reputation for engineering. That's why it has built the 102EX. And it seems quite prepared for its customers to hate it.

Because a Rolls-Royce is already so furiously expensive, the cost of the battery, which usually distorts the price and economics of ordinary electric cars, is much less significant, and Rolls can simply fit the biggest the car will take. So up front is what Rolls believes is the biggest battery ever fitted to a passenger car: 96 lithium-nickel-cobalt-manganese-oxide cells in total, with a capacity of 71kWh. Three chargers sit on top of the pack; a full charge takes between eight and 20 hours depending on supply. There's a five-pin recharging socket in the hatch in the C-pillar vacated by the fuel filler, and an induction-charging plate underneath that will allow you to charge up by driving over a similar plate in the heated floor of your garage. Two 145kW AC motors sit above the rear axle and drive it through a single reduction gear and an open differential.

It isn't a technologically radical drivetrain; Rolls decided that electrifying a Phantom was enough to begin with. The styling isn't radically different either, again to keep the focus on the tech. The Spirit of Ecstasy is made of translucent Makrolon polycarbonate and lit with blue LEDs, and the RR logo is red, as it always has been on experimental models.

The numbers do stand out. The 102EX makes a total of 388hp, down from 453hp with the V12, but torque goes up 10 per cent to 800Nm. At around 2,700kg, mass is up less than 200kg, but that monstrous torque means the Phantom will still hit 100kph in less than eight seconds. It's limited to a top end of 160kph.

But forget all the figures. Numbers can't describe what it's like to drive an electric Rolls-Royce. The 102EX makes a strong claim to be the most refined car ever made, and driving it is one of the weirdest experiences I've had at the wheel. The effortless, almost silent way it surges away from the car park will be familiar to anyone who's driven a modern electric vehicle. There's a faint sigh from the twin electric motors behind the rear seats; the engineers could have damped it all away, but I like it.

Because a Rolls V12 is so refined anyway, the contrast between petrol and electric isn't as great as it is in other electrified cars. In those other cars, the absence of the noise and vibration of an engine means you notice more suspension, tyre and wind noise; they're not louder, plainly, but just more noticeable, and not good to listen to. But because the Rolls still has arguably the best chassis refinement of any car, there isn't anything much left to hear or feel. Driving the 102EX is like sitting in the sofa you might be reading this from; your eyes tell you you're moving, but your body totally disagrees. You don't feel disconnected; you're still in charge, and despite being powered electrically rather than hydraulically, the steering and brakes still have the same weight and feel. It's eerie-delightful; it made me giggle aloud the first time I moved off, and I think Rolls-Royce owners are going to love it.

The Rolls-Royce engineers aren't so happy. I started off driving incredibly carefully, not out of respect for the car's range but instead for its total irreplaceability; this car, as the chief executive said in that speech, is the future of the company. But like any other Phantom, the 102EX drives with an ease and grace that belie its size; the high driving position and great square plateau of bonnet - surely the best view in motoring - impart complete confidence.

So I soon reverted to the way you'd usually drive a Phantom; one arm on the broad, high door sill, the other using just a finger to twirl the breadstick-thin steering wheel. I wasn't consciously trying to maximise the range, but a Rolls and an EV ought to be driven the same way; smoothly and seamlessly, lifting off early when you see an obstruction, braking as little as possible and observing the speed limits. Like other good EVs, the Rolls is an immensely relaxing thing to drive; not only is there no noise and only one gear, but you seldom need to shift your foot to the brake because the gentle braking effect of the motors as they become generators generally slows you enough anyway, so you drive this vast, priceless car with just a flex of your right ankle and a flick of the thumb.

But the engineers had made a graph of energy use against distance that I can't pretend to have understood, and according to their calculations we were some way south of the "critical path". From the car behind they called the Rolls-Royce guy travelling with me, and in the utter calm of the cabin I could hear what they were saying. "SLOW DOWN! You've got to get him to slow down. And make him use low mode all the time to get more charge into the battery."

Of course I took no notice. My own complex calculations, which involved squinting at the battery metre and the odometer and reckoning that we'd used about a quarter of the juice when we were roughly a quarter of the way around, said it would be close. I wanted it to be a fair test, and the bad part of me said you'd find it much funnier if we ran out and had to be recovered. At our lunch stop, just beyond the halfway point, the engineers plugged their laptop in again, read the car's state of charge, and again pleaded with me to slow down. From Goodwood, Rolls-Royce's urbane public relations director, was constantly on the phone to his man in the car with me, asking for updates.

On the final leg the "fuel" gauge was falling more slowly than the kilometres were accumulating; I don't know whether we were drawing less power or if the gauge wasn't perfectly linear, but with about 50km to go my bad maths told me we were going to make it. So to the utter distress of the engineers behind, I started hoofing the Phantom away from junctions. And I'm pleased to report that it feels pretty good; deliberately gentle up to about 30kph, when the vast weight is overcome by even greater torque and you get a lovely, irresistible surge. It might not be as fast as a V12, but it's fast enough.

I'd been worried before we set out that Rolls-Royce knew they had an extra 80km of range in their back pocket. When we pulled back into the hotel car park in Lausanne with exactly 180km on the odometer and a little less than a quarter still remaining on the charge gauge, I again wondered if I'd been had. But the look of utter relief on the face of the young engineer tasked with getting the 102EX around the lake without public embarrassment couldn't be faked. I thought he was going to kiss me.

Does it matter how far you can drive a car Rolls-Royce say is purely experimental and will never be built? I'd say yes; by putting such a big battery in such a big car, it shows the limits of the possible. It's the first real exploration of how super-luxury cars might drive in 20 years' time. And despite its protestations, Rolls-Royce is going to find it very hard to resist the customers who will come to it with open chequebooks once they've driven this extraordinary car, asking for a 102EX of their own.