Hilltop Reserve

[oilerlord]

10% is pretty good, actually. Typical L2 efficiency is 85-90%. L1 can as low as 75% for 12A, even less at 8A (due to constant loads running over a longer time)

That's good to know. On my car, I can set it to charge on L2 at "maximum" (up to 40 amps), 13, or 10 amps. I often vary the charge rate as my solar generation fluctuates from day to day. Perhaps I shouldn't...is charging at 13 amps (on L2) less efficient than charging at 40 amps?

 

[GetOffYourGas]

10% is pretty good, actually. Typical L2 efficiency is 85-90%. L1 can as low as 75% for 12A, even less at 8A (due to constant loads running over a longer time)

That's good to know. On my car, I can set it to charge on L2 at "maximum" (up to 40 amps), 13, or 10 amps. I often vary the charge rate as my solar generation fluctuates from day to day. Perhaps I shouldn't...is charging at 13 amps (on L2) less efficient than charging at 40 amps?

Generally speaking, L2 charging at a higher rate will be more efficient. Most EVs have fixed loads that run while charging, so you are minimizing the time running those loads. I cannot speak to your specific car, though. Mercedes might not have a significant load, but may have chosen a charger which is less efficient at higher current (e.g. I^2*R losses in the charger/battery). Which effect trumps the other may vary from car to car. But my guess would be 40A is most efficient.

I don't really worry about charging efficiency - EVs are already so efficient and electricity is cheap enough that it doesn't matter much. I often charge at L1 simply for convenience.