Mercedes-Benz added a new model to its S-Class line at the 2013 Frankfurt Auto Show, with the introduction of the 2015 S500 Plug-In Hybrid.

Based on the redesigned 2014 S-Class sedan, the S500 is powered by a turbocharged 3.0-liter gasoline V-6 with 328 horsepower and 354 pound-feet of torque, along with an electric motor that adds 80 kilowatts (107 hp) and 250 lb-ft.

The motor gets its electricity from a lithium-ion battery pack in the trunk.

That combination will hustle the S500 Plug-In from 0 to 62 mph in a remarkable 5.5 seconds, and on to an electronically limited top speed of 155 mph.

On the economy front, the plug-in S-Class has an electric-only range of approximately 18 miles.

Mercedes estimates fuel economy at 78 mpg on the European combined cycle; as always, that number should be taken with a large grain of salt pending EPA range and gas-mileage ratings.

Mercedes also gives S-Class drivers choice of four driving modes. "E-Mode" is electric-only, "Hybrid" adds the gasoline engine to the mix, "Charge" prioritizes battery charging, and "E-Save" holds the battery's charge for later.

Drivers can monitor what's going on via the dashboard screen, and the accelerator pedal's resistance also adjusts to help evenly mete out power.

Managing it all is Mercedes' Intelligent Hybrid system. It analyzes driving conditions, including predicting the likely route based on the past five miles of driving, and deciding what combination of gasoline power, electric power, and regeneration is best for a given situation.

Check out more 2013 Frankfurt Auto Show coverage here on Green Car Reports.


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