What is it?
The first of Porsche’s facelifted Panamera models, the S E-Hybrid.
The advanced petrol-electric hybrid, due to go on sale in the UK in August, replaces the earlier pre-facelift Porsche Panamera S Hybrid with some traditionally subtle exterior styling changes but, at the same time, significant modifications to its petrol-electric driveline, including a new on-board charger that forms part of the plug-in system and the adoption of a liquid-cooled lithium-ion battery in place of the older air-cooled nickel-metal hydride unit, among other detailed tweaks.
The result is a significant improvement in driveline efficiency and solid gains in performance, together with a big reduction in fuel consumption and CO2 emissions. The best of both worlds, or so Porsche would have you believe.
It is not all rosy, though. The changes to the driveline bring an additional 115kg in kerbweight over the old Panamera Hybrid, bumping it up to a hefty 2095kg – 325kg more than the entry-level Panamera.
The headline figures for the Panamera S E-Hybrid are its claimed combined cycle average of 91.1mpg and CO2 emissions of just 71g/km. According to Porsche’s claims, it can also dispatch 62mph from standstill in 5.5sec, 124mph from standstill in 19.0sec, 50mph to 75mph in 3.4sec and a reach a top speed of 168mph flat out.
A further drawcard is its ability to run on electric power alone for distances well in excess of its predecessor thanks to the new battery, which boasts a greatly improved energy density and capacity that is increased over five fold at 9.4kWh. The figure varies with the topography of the road; official claims based on the controversial European test cycle procedure for hybrid powered cars puts it at 22.4 miles, although Porsche engineers suggest the real world range is actually between 11.2 and 22.4 miles. By comparison, the old Panamera S Hybrid was claimed to offer just 1.2 miles. Top speed in electric mode is an impressive 84mph.
The recharging time for the battery, meanwhile, is put at four hours on a 240 volts system and two hours on a 400 volt high charge system.
Power is provided, in part, from an Audi-sourced supercharged 3.0-litre V6 direct injection petrol engine that delivers 328bhp and 324lb ft of torque. It is mated with a brushless electric motor that produces 94bhp and 228lb ft of torque. Combined, the two power sources provide the Panamera S E-Hybrid with 410bhp at 5500rpm and 435lb ft of torque on a band of revs between 1250 and 4000rpm. Drive is sent through a standard eight speed automatic gearbox to the rear wheels.
Underneath, Porsche has tweaked the suspension of the Panamera in a bid to provide improved levels of low speed comfort. Larger chassis mounts are incorporated up front for added rigidity, the flow of oil within the adaptive dampers has been improved for added response and the software for the air springs has been recalibrated. The big liftback also receives a new range of alloy wheels, which use so-called flow forming construction to lower weight and a reduction in unsprung masses.
What’s it like?
As complex as the Panamera S E-Hybrid’s driveline may appear – and, make no mistake, it is at the very cutting edge of automotive technology – the big four-seater is remarkably straight forward to drive. Which is exactly what Porsche says its customers demanded when they sat down with them to discuss what they expected of the world’s first plug-in petrol-electric luxury car.
Porsche has conceived its latest hybrid to offer four different driving modes: E-Power, Hybrid, E-Charge and Sport. The driver can override the system and choose to select a particular mode via buttons on the centre console, but the system is so intuitive it is better to leave it to its own devices for the best possible fuel savings.
The default mode is E-Power; as long as there is sufficient charge in the battery it will always use the electric motor to set off. Refinement levels in this mode are spectacular – every bit as impressive as a pure electric car, with only the sound of the tyres rolling across the bitumen to spoil the silence.
Just how long it continues like this depends on how much charge is in the battery and how much throttle you use. In press-on driving or when electric energy levels run low it automatically switches out of E-Power mode into Hybrid mode.
A string of information can be called upon to keep tabs of factors such as battery charge, remaining electric range and to ensure the highest possible efficiency and charging possibilities.
The E-charge mode allows the battery to be charged on the run, but it involves a firing of the petrol engine, which acts in part like a range extender by providing a small charge to the battery on top of the kinetic energy recuperated under braking and periods of trailing throttle.
On a 32 mile route mapped out at the launch of the new car in Germany this week, we managed to get the Panamera S E-Hybrid to remain in E-Power mode for almost 31 miles at an average speed of almost 30mph over a variety of roads, including city driving conditions, leaving us with indicated fuel consumption of 1413mpg.
On the return leg, with the battery charge depleted and less favourable topography, the petrol engine was in continuous operation, providing an overall figure of nearly 86mpg at roughly the same speed.
They’re impressive figures. But in real world driving conditions it is a rather different story, with overall consumption that is close to the Panamera Diesel, which now returns a combined cycle figure of almost 45mpg.
The big advantage over the old Panamera S Hybrid is the scope provided by the on-board charger to top up the new lithium ion battery using mains power, say overnight or during working hours. This provides it with the ability to run in pure electric mode for extended periods – something that makes the Panamera S E-Hybrid particularly well suited to everyday commuting.
Fortunately, there’s more to this latest Porsche model than pure electric driving. Switching into Sport mode unleashes the full potential of the driveline, in which the petrol engine and electric motor combine to provide more than adequate levels of performance.
At 2095kg, there’s significant mass to shift. But with solid low end torque, thanks in part to the inherent properties of the electric motor, there is a good turn of speed out of the blocks and through the gears, as revealed by Porsche’s own performance claims. The Panamera S E-Hybrid undercuts the Panamera Diesel’s 0-62mph time by a full 1.3sec and 0-124mph time by a full 11.4sec. Part throttle cruising qualities, meanwhile, are hard to fault, with subdued engine noise, low levels of wind buffeting and excellent longitudinal stability.
The additional weight brought on by the hybrid system is only really noticeable on more challenging roads, where you find yourself backing off in corners where you’d still be pressing on in the more inherently sporting Panamera S. The brakes, however, are superb, with excellent feel and massive stopping power. The modifications to the suspension also help improve low-speed ride, bringing greater levels of comfort without any detriment to the way it absorbs irregularities at higher speeds.
Should I buy one?
Up until now the S Hybrid has accounted for around five per cent of worldwide Panamera sales. With the introduction of the new S E-Hybrid, Porsche expects that number to at least double.
The new plug-in technology brings a much improved electric range and provides clear scope for added fuel savings in real world driving conditions.
The appeal of the new car will surely spread beyond early adopters to those who see the second generation hybrid systems as more than a mere gimmick. They won’t be disappointed.
Porsche Panamera S E-Hybrid
Price £88,967; 0-62mph 5.5sec; Top speed 168mph; Economy 91.1mpg; CO2 71g/km; Kerbweight 2095kg; Engine V6, direct injection, supercharged, petrol, 2995cc; Power 410bhp at 5500rpm; Torque 435lb ft from 1250-4000rpm; Gearbox 8-spd automatic
What is it?