Many were surprised that Porsche – the marque with more wins at Le Mans than any other – beat almost everyone to putting a plug-in hybrid car in its showrooms. After all, Porsche is a purveyor of very, very fast cars, while electric motors have so far been mainly used to boost efficiency at the expense next-level supercar performance.
With the arrival of the salivatory 918 Spyder, however, electric propulsion is now firmly entrenched in the German carmaker’s engineering DNA. Plug-in hybrid versions of the Cayenne and – shock, horror – the iconic 911 will arrive in the near future, too, and the decision to pursue the technology early doors looks a smart one.
For now though Porsche’s four-door coupé-cum-sedan is the only reasonably accessible car in the range to offer the zero-emissions hardware, boasting notable improvements over the non-plug-in Panamera S Hybrid it replaces in every area. But you’d be well within your rights to expect that from a car costing $96,100.
What prospective buyers will want to know is whether it’s worth the premium over a Tesla Model S or, perhaps more interestingly, the standard Panamera models.
Impressive new hardware
Take it as read that the Porsche Panamera is a high-class product. The instrumentation is crystal clear and there’s not a stitch out of place on the copious leather trim. The wide, highly adjustable front seats are also mirrored in the rear, with passenger comfort prioritized over a space for a fifth, and despite its sporting pretensions quiet conversation is possible even at autobahn speeds.
Architecturally, the brand’s newfound fondness of a high and wide transmission tunnel joins the high beltline in making the Panamera feel exactly what it is: tank – safe, secure, and hugely comforting to travel in. Here, all the clichés concerning robust German engineering apply.
What the S E-Hybrid brings to the Panamera nameplate is a substantial 9.4 kWh lithium-ion battery pack that can be charged from the mains to deliver 22 miles of zero-emissions driving in the right conditions (although he US Environmental Protection Agency rates range at 16 miles). As we’ve discovered, you’ll do well to get that kind of range out of a full charge, but the larger battery pack’s positive implications for everyday driving are considerable.
The rest of the time motivation comes from a baritone 3.0-liter V6 developing 333 hp, although the way the two power sources work together is the most impressive of any plug-in hybrid car we’ve tested (this week’s Volkswagen Golf GTE launch may change that, however).
The handover of responsibilities from the engine to the electric motor, and vice versa, is seamless every time. And because both put their power through the same eight-speed dual-clutch transmission the two work beautifully in unison. Porsche demonstrated that it is perhaps the best in the world when it comes to calibrating this kind of complex relationship between two disparate power sources with the 918 Spyder, which adds four-wheel drive into the mix.
The driving experience
The Panamera S E-Hybrid always defaults into pure electric mode; the only way you’ll know the 2.1-tonne behemoth is primed is because the acid green needle in the centre-left binnacle leaps to ‘READY’.
Squeeze the throttle and it whispers into motion, that same needle climbing up and around a power gauge that has replaced a more traditional speedometer. In the middle is Porsche’s iconic tachometer; to the right is a digital display that neatly toggles information pertaining to everything from battery charge to the song you’re listening to through the car’s optional 14-speaker BOSE sound system ($1,590 and worth every cent).
Press the button marked E-POWER and you’ll stave off any oil burning activates until battery charge is so low that there’s barely enough power to turn the wheels. In this way the Panamera S E-Hybrid is quite simply the most luxurious electric car in the world, effortlessly cruising up to its limited top speed of 85 mph should you need to.
Pure electric mode is best deployed in urban environments, however, and not only for philanthropic reasons. The car is unnervingly smooth, and without wind noise or tire roar it’s also quieter than a Mercedes-Benz S-Class, with truly wraith-like qualities.
Our test notes do reveal, however, that in typical city driving actual electric range was just 60 percent of estimated electric range, which is irritating when there’s only a notional 22 miles to play with in the first place. Perhaps the next generation car will have a much larger, floor-mounted battery pack in place of the current unit that gobbles up a little bit of rear cargo space.
With E-POWER deactivated, squeeze the throttle harder and you’ll awaken the engine. With a combined 416 hp now at your disposal, accessible by engaging kick-down, the car is transformed. Porsche calls this ‘Boost’ mode, which is appropriate because the blend of immediate electric torque and subsequent muscle from the twinturbo engine results in frankly indecent acceleration for a car of this size. For some perspective, consider that the Porsche is fractionally faster than even a Tesla Model S P85 between 50 and 75 mph.
You’ll only really use both power sources together for overtaking – and simply for the fun of it – however.
As the Panamera S E-Hybrid will spend the majority of its time, at least on journeys, powered chiefly by its engine, we were pleasantly surprised to see it return exactly 30 mpg on 200-mile highway stint sandwiched by congested city driving and undulating rural roads. That was enough to beat the car’s combined EPA rating 25 mpg (an average of 23 mpg city and 29 mpg highway).
The decisive factor in such a large, powerful car’s ability to sip fuel is its decoupling feature, whereby the engine disengages from the transmission and shuts down off-throttle. The car does this frequently, and if a fraction of power is required to sustain cruising speeds it’s typically provided by the electric motor, allowing the engine to remain dormant.
Likewise in the urban congestion, the Panamera S E-Hybrid can creep along using very little electric power. It means that even when the battery is seemingly depleted of charge, traffic jams are a carbon-free affair. You simply won’t burn fuel.
Still a sports car?
It would be easy to assume that an emphasis on plug-in hybrid technology and the 115 kg penalty the additional hardware brings mean this Porsche has lost its edge.
This isn’t at all the case. The Panamera S E-Hybrid corners hard with more grip than you should ever really need and very little body roll. It also steers with gratifying conviction and, despite its cumbersome dimensions, is capable of putting a smile on the driver’s face along the right road. Quadruple wide bore exhaust tips and their throaty blare are an indication that this car’s emphasis is still firmly on performance.
One feature of the Panamera S E-Hybrid that Porsche trumpets is its ability to recharge the battery on the move by siphoning power from the engine. In theory the idea is a good one, permitting the driver to enter a destination city in electric mode despite leaving home or work with a depleted battery, but there are flaws.
One is that the engine stays on even when it could shut down for coasting, but far worse is the drop in efficiency. At a steady 70 mph our car was 30 percent less fuel efficient in E-CHARGE mode than in standard hybrid mode – a huge discrepancy. If, however, the battery charge gained in E-CHARGE mode is subsequently used for pure electric driving during the same journey, overall energy loses – and as a result any changes in fuel economy – are negligible.
The best thing to do is to keep the car charged up. Buy a Panamera S E-Hybrid and Porsche will come round and install an elegant wallbox charger capable of replenishing the lithium-ion battery pack (that’s larger than the one in the 918 Spyder) in roughly two hours.
The bottom line
Almost $3,000 dearer than the equally powerful Panamera S and a hefty $18,000 more expensive than the entry-level model, the Panamera S E-Hybrid isn’t cheap.
In the real world, however, it’s faster than both those cars and the addition of an electric motor supplements already sky-high levels of refinement. In the right scenario it’s potentially far cheaper to run too while costs are further reduced by a generous $4751.80 federal tax credit.
Although the two are technologically dissimilar, the Porsche’s status as an ecological statement means that comparisons will be drawn with the Tesla Model S. In its favor are build quality that the American car simply can’t match and driver feedback that makes the pure electric sedan feel utterly inert.
Range anxiety will never rear its ugly head in the Panamera, either, although the Tesla’s 265 miles of autonomy is more than enough for most. In performance terms the two are well matched, but perhaps the Tesla edges in terms of the pure thrills of massive torque and relentlessly smooth acceleration.
That leaves the Panamera’s common foes: Audi’s A7, the Mercedes-Benz CLS, and the BMW 6 Series Gran Coupé. You can buy stupidly powerful versions of all these cars, but none of them can yet do a convincing impression of a full zero emissions vehicle on the daily commute. They lack versatility.
While describing it as ‘green’ may be a little dishonest, for now the Porsche Panamera S E-Hybrid is a unique and hugely convincing proposition. One criticism the car perhaps fairly attracts is the design though which, despite the protestations of Porsche design boss Michael Mauer, is awkward.
The four-door Porsche is rarely bought for its good looks, however, rather for its class-leading abilities, and this particular model has a far broader skill set than it’s numerous siblings.