Most likely reasons would be differences in the algorithms used to calculate that stuff and/or a slight loss of eco juice that occurs during charging - nothing is 100% efficient.

Hi ​@Blastoise186 

thanks for the reply. I guess the EV could be as high as 28.9999 (it only shows whole units), but that’s around 4% losses and wouldn’t expect differences in algorithms to make that level of difference - there must be standards for calculating current/ kWh.

I was thinking it may be more likely that the battery charge may have gone up by 28kWh, but other EV car functions have taken up the remainder e.g battery warming, cabin cooling etc, which have come directly off the mains.

it makes it hard to compare total charging costs if the EV isn’t counting everything!
 

cheers,

colin

​@Colingray83 the charging process (AC to DC) within the car is typically 90-92% with inverter losses and static losses that ​@Blastoise186 mentioned above.

Peter

Pesky electrons. Thanks for the explanation, that makes a lot of sense.  Though still makes it hard to work out charging costs.

colin

You probably wouldn't be far out if you used a figure of 92% when charging at 7kW. 88% for 3.5kW. I did a lot of data collection with my car comparing what was registered by the car and comparing that with what was supplied through the meter.