We know the vehicle is a plug-in because of the small cap located on the left side of its rear bumper. This is the same location that the cap concealing the charging port on the S-Class Plug-In Hybrid can be found.
First previewed in 2009’s Vision S500 Plug-In Hybrid concept, Mercedes-Benz’s hybrid drivetrain pairs an internal combustion engine in parallel with an electric motor integrated with the transmission. While the setup in the S-Class utilizes a turbocharged V-6 for the internal combustion element, we suspect this C-Class Plug-In Hybrid will feature a turbocharged four-cylinder. A lithium-ion battery will sit in the trunk.

2016 Mercedes-Benz C-Class Plug-In Hybrid spy shots
The car is expected to be badged a C350 Plug-In Hybrid and return gas mileage of 78 mpg or better. Of course, reaching such lofty figures will depend on how much electric-only driving is done. On electric power alone, owners should experience a range of approximately 31 miles.
Note, Audi has confirmed that its next-generation A4 will feature a plug-in option, and a plug-in hybrid BMW 3-Series has also been spotted. For more on the latest C-Class, read our first drive report on the 2015 model.
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