What is it?
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.