Porsche Panamera S E-Hybrid

I can only liken it to a silent soundtrack from a roaring lion.

Yet a few miles down the road I am accompanied by a growl from the 3.0-litre supercharged V6 engine that until now has played only a bit part in my journey.

This is the Panamera S E-Hybrid, an extremely clever piece of engineering, which a combines combustion engine and electric motor to give the car extra accelerative punch at the first touch of the throttle while at the same time achieve extraordinary economy and emissions figures alongside tax benefits.

Three things give identity clues to the E-Hybrid: an inscription on its flank, bright lime green brake callipers as opposed to the usual red and what appears to be an extra fuel filler cap, but is in fact hiding the plug-in point when it needs a top-up of electricity.

Otherwise, it's pure Panamera - and that means XL in all areas: 20-inch wheels, five-metre length 2,095kg weight and four tailpipes peering out the back.

Which leads one to question whether the Panamera is in fact a grand tourer rather than a sports car. Depending on your journey and the road conditions, it's both.

The most remarkable figure you come across when checking out the Panamera statistics is none of the above, however. It's not even the 71g/km CO2 emissions figure (although that certainly raises an eyebrow or two).

No, it's the claimed 91mpg fuel economy, the sort of figure that might surely only be achieved by something in the lightweight class with no balls but plenty of volts.

There’s a wonderful spread of engine technology in the Panamera range, from naturally aspirated V6s to a supercharged V6 hybrid, a V6 diesel and a turbocharged V8. Each car has a different character. The S E-Hybrid has a super throttle response. The eight-speed Tiptronic automatic gearbox can be a little slow to kick down at times, but it instantly wants to surge forwards. That’s thanks to the supercharger and electric motor, and the end result is a huge, and seemingly endless reserve of power that carries on long after you reach high speeds very, very quickly.

What’s most surprising about the car on the road, though, is that given how heavy it is, how controlled it is. The Porsche Active Suspension Management (PASM) has three modes; Comfort, Sport and Sport Plus. The options are mirrored by the gearbox settings, and turning everything up to Sport Plus creates a car that is amazingly capable, regardless of what challenges the road throws its way.

The electric drive produces 95bhp, which is more than double the power of the previous model’s 47bhp electric motor. It draws energy from a new lithium-ion battery which can be charged in less than four hours when connected to a conventional household electrical outlet.

With its increased output, the Panamera S E-Hybrid far exceeds the driving performance of the previous model. In addition, the fuel economy has increased by 56 per cent to that astonishing 91mpg figure. Furthermore, the all-electric driving performance has been substantially improved with regard to electric acceleration, the electric range and electric top speed.

In a week of road testing I found it difficult to gauge what sort of mpg figure could be achieved. On one particular journey the trip computer showed an mpg figure of more than 400 miles, but more often than not I was achieving no more than 45mpg. Road and traffic conditions will obviously dictate what is achievable.

An intensive pure electric driving experience is possible without any fuel consumption or local emissions. The electric driving range of the Panamera S E-Hybrid has been determined as 22 miles in test conditions, although all-electric driving range in everyday operation will more likely be between between 11 and 22 miles.

With a top speed of 84 mph in all-electric operation and the acceleration time from 0-62 mph of 5.5 seconds, the electric boost function is a significant factor in the car's performance figures. Not only has it a top speed of 168mph, but it can also coast at higher speeds with the internal combustion engine shut off and electricity geberated by energy recovery.

Standard equipment on all models includes bi-Xenon headlights, automatic tailgate opening, leather interior, dual-zone automatic climate control, front and rear parking sensors, cruise control, satellite navigation with seven-inch screen, eight-way powered front seat adjustment and front and rear electric windows.

The ultra-low emissions ensure the Panamera S E-Hybrid qualifies for a number of fiscal benefits and capital allowance benefits for business customers.

Tax savings are all well and good, but with a list price of nearly £86,500 before you go anywhere near the options list, the S Hybrid is about £23,000 more expensive than the similarly frugal diesel version that’s very nearly as quick, and even at current prices you can buy a lot of diesel for that much spare cash.

The truth is that while the diesel will appeal more to European buyers, American and Chinese buyers would pay the extra for the petrol car. And if you have the money, it’s a terrific car to own. There’s little or nothing it won’t do, and do as well or better than almost anything else.

At a glance

Porsche Panamera S E-Hybrid

Price: £88,967 (Panamera range from £65,269)

Engine: 3.0-litre supercharged 333bhp V6 petrol combined with 95bhp electric motor to produce 416bhp

Transmission: Eight-speed Tiptronic gearbox driving the rear wheels

Performance: 0 to 62mph in 5.5 seconds; top speed 167mph

Economy: 91.1mpg combined

CO2 emissions: 71g/km