So apparently Mercedes is launching a C and E-Class diesel PHEV at Geneva.
The claimed specs are a 90 kW (121 hp) electric motor, with a 13.5 kWh battery, and about 50 km NEDC range. (Note that 50 km is something that a lot of German PHEVs target, I think there’s tax incentives or something in Germany for hitting that.)
However, NEDC is notoriously lax as far as test cycles go - after all, it was designed such that a 30 hp diesel shitbox could make it through the test without failing for going too slowly. In my experience, if something claims 50 km NEDC, it’ll be right around 16 miles on the EPA test, which is actually realistic.
13.5 kWh / 16 miles means 844 watt-hours per mile. That’s not fair, though - after all, there’s usually a buffer, and assuming there’s a 20% buffer (pretty typical for a PHEV), you’re looking at around 700 watt-hours per mile in electric mode.
Compare to the giant barge of the Chrysler Pacifica Hybrid, at 400 Wh/mi in electric mode.
Compare to the Tesla Model S 100D, which is kinda in the size class of the E-Class, at 330 Wh/mi.
Compare to the Tesla Model 3 Long Range, competing pretty directly against the C-Class, at 260 Wh/mi.
Turns out the Germans do have a sense of humor...