What is it?
The plug-in hybrid version of the new Mercedes E-Class, which will be the first petrol-powered version to arrive in the UK, touching down before the end of the year. The E 350 e uses the combination of a turbocharged four-cylinder engine and an electric motor to deliver a combined peak output of 281bhp and what Mercedes predicts will be official fuel consumption of 134mpg and CO2 emissions of 49g/km.
Stop sniggering at the back, we know that achieving anything close to those numbers in the real world will mean making extensive use of the ability to recharge the 350 e’s 6.2kWh capacity battery pack using the charging port built into the rear bumper. This can replenish the pack in around an hour and a half using a high-voltage charger, or three hours via a standard domestic socket. The car’s electric-only range is a relatively modest 20 miles, but several different modes allow the assistance to be used or conserved in different ways.
These modes are Hybrid, which leaves the powertrain to its own devices; E-Mode, which operates it as a pure EV until the battery pack runs down; E-Save, which keeps the battery level constant, conserving it for use later; and Charge, which uses the engine to replenish the pack on the move. The system also communicates with the sat-nav so that when a destination is programmed it will work out the most efficient strategy over the entire route, for example, running the battery right down if the car knows it will end up at its home charging point.