There appears there might be a considerable efficiency in charging your roadster at lower Amps vs high Amps. When I charge at 40 Amps 240v The fans turn on full power and the cooling system runs the entire time. When charging at 12 AMP the fans almost never turn on and just the pumps flow coolant. Therefore it should be more energy efficient to charge at lower amperage. Can anyone confirm that has a separate meter for the car?