In the plug-in hybrid game, you move forward or get left behind. When the hybrid maker is Porsche, that applies to power as well as efficiency.

The 2018 Porsche Panamera 4 E-Hybrid is the replacement for the previous Panamera S E-Hybrid, and it gets more power, performance, and efficiency in a brand-new vehicle.

Everything about this car is new. In fact, Porsche says, the only things that carry over are the idea of a sport sedan, the name, and the Porsche badge.

DON'T MISS: 2014 Porsche Panamera S E-Hybrid: Gas Mileage Review (Apr 2014)

The car is based on the Volkswagen Group's new MSB modular platform, which can accommodate three wheelbases.

Porsche employs a multi-material approach that includes aluminum and high-strength Boron steel to produce a body that is 144 pounds lighter with 8 percent more torsional stiffness.

Enough about the platform, and on to the hybrid components. They start with a new Porsche-developed twin-turbocharged 2.9-liter V-6 that replaces an Audi-sourced 3.0-liter supercharged V-6.

Power is similar: it produces 330 horsepower and 331 pound-feet of torque, while the last engine made 333 hp and 325 lb-ft of torque.

2018 Porsche Panamera 4 E-Hybrid motor and transmission

2018 Porsche Panamera 4 E-Hybrid motor and transmission

The electric motor increases from 70 kilowatts (95 hp) and 229 lb-ft of torque to 100 kw (136 hp) and 295 lb-ft, and it moves from between the engine and transmission to inside an all-new 8-speed dual-clutch transmission (or PDK in Porsche speak). That transmission replaces an 8-speed automatic.

Total it all up and system output increases from 416 hp and 435 lb-ft of torque to 462 hp and 516 lb-ft of torque.

The motor can power the car by itself, or aid the engine. It is powered by a larger lithium-ion battery that is located in the trunk.

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At 14.1 kilowatt-hours, the battery is 50 percent larger than the 9.4-kwh pack it replaces, though it takes up no more space than the old one.

Porsche says the Panamera 4 E-Hybrid can drive for 50 kilometers (31 miles) on electricity alone on the New European Driving Cycle. U.S. testing procedures are more stringent, so its EPA ratings won't be that high.

However, if it goes half again as far as the 15-mile range of the S E-Hybrid, it would deliver 22 or 23 miles of rated electric range.

We don't know exactly how efficient it is either. EPA energy-efficiency and fuel-economy numbers aren't available yet.

For reference, though, the 2016 Panamera S E-Hybrid had a 51 MPGe rating and a combined city/highway rating of 25 mpg.

We expect combined fuel economy in the 26 to 28 mpg range for this car, given its incremental improvements to the hybrid components.

CHECK OUT: Porsche's 800-Volt fast charging for electric cars: why it matters

Charge times? According to Porsche, a 120-volt outlet will do the trick in 12.5 hours.

An optional 240-volt portable charging cord will be offered with a 7.2-kilowatt capacity that will cut the charge time to 2.4 hours.

2018 Porsche Panamera 4 E-Hybrid

2018 Porsche Panamera 4 E-Hybrid

2018 Porsche Panamera 4 E-Hybrid

2018 Porsche Panamera 4 E-Hybrid

2018 Porsche Panamera 4 E-Hybrid

2018 Porsche Panamera 4 E-Hybrid

How does it drive?

The 4 E-Hybrid's driving character is determined by the drive mode you choose: it always starts out in E-Power mode, running on electricity alone. But it also has a Hybrid Auto mode, plus Sport and Sport+ modes.

In E-Power, it will run on electricity up to 86 mph, provided you don't floor it past a detent in the pedal stroke.

In E-Power, the car has enough thrust to handle every day traffic duties despite the fact that you are running on only 136 hp and 295 lb-ft of torque.

ALSO SEE: Do Tesla Model S And Porsche Panamera Plug-In Hybrid Compete? (Jul 2013)

Freeway merging could be an issue in fast-moving traffic, but the engine will kick in if you go past that detent then shut off once you ease off.

Porsche provides two other modes within E-Power: E-Hold and E-Charge. E-Hold conserves electric power at its current state and E-Charge uses the engine to charge the battery, running rather inefficiently while doing so.

Both could help when approaching emissions-free zones in European city centers.

2018 Porsche Panamera 4 E-Hybrid

2018 Porsche Panamera 4 E-Hybrid

2018 Porsche Panamera 4 E-Hybrid

2018 Porsche Panamera 4 E-Hybrid

2018 Porsche Panamera 4 E-Hybrid

2018 Porsche Panamera 4 E-Hybrid

In the E-Hybrid Auto mode, the car seeks to run most efficiently, using the engine, motor, or both to achieve the best fuel economy. While the former S E-Hybrid required the throttle to be at least 80 percent of the way to the floor to get the motor to kick in, electric assist is now available at all times.

Like the rest of the car, the regenerative braking system has been upgraded, slowing the car for any braking event that is 0.3 g or less (vs. 0.15 g for the last model). Once the car reaches about 9 mph, the mechanical brakes handle the rest.

The brakes can feel grabby--a common problem for hybrids--and the hand-off to the mechanical brakes is sometimes apparent to the driver. The feeling isn't entirely natural, but most owners will likely get used to these minor bugaboos.

Drivers who are so inclined can treat the Panamera hybrid as a full-on performance machine. Choose Sport or Sport+ and the power becomes much more accessible. Mash the throttle and this beast provides immediate, thrilling acceleration—hitting 60 mph in just 4.4 seconds. Stay on it and it tops out at 172 mph, but only in Sport+.

2018 Porsche Panamera 4 E-Hybrid

2018 Porsche Panamera 4 E-Hybrid

Bottom line

The 2018 updates will come at a cost premium of about $6,000. The Panamera 4 E-Hybrid hits dealers this summer with a starting price of $100,650; the longer-wheelbase Executive model will run $105,150.

For your six figures, you get a big, comfortable, great-handling luxury sedan that you can drive as a performance machine or plug in overnight and drive using little or no gasoline if your travels only take you 20 miles or so.

It's not entirely a green machine, but Porsche's hybrid sedan is getting more efficient—and more powerful—as time marches on.


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