Load loss

[NLMGSAN]

When I added up all the kwh's from the bills and divided it by the distance driven, I ended up at 17.6 kwh per 100 km's. I'm not 100% what the consumption rate is since it had a reset at the dealer and after 100 hrs, but per 100 it will be close to 16 per 100. Which makes for a 10% load loss.
However, given that I had 18% left yesterday, and doing a 100% calibration load with 62.38 kwh, my ER needed 75.78 kwh for a full load of 74.4 effective kwh's available for driving. That is much less than 10% load loss.
How do you calculate load losses?

 

[webhiker]

There are different load loss under different circumstances.
Load loss is paid for load minus received load. If you want to calculate it even further you need paracetamol ?

 

[fnegroni]

AC charging is not the most efficient especially above 3.6kW as the losses increase. Plus when your battery hits the higher states of charge, some of the power is redirected to the battery cooling or heating depending on the battery temperature; if you charge and have the lights on or the HVAC on etc that reduces what goes in the battery even further.

just because the car said you had 18% remaining doesn’t mean you can precisely say how many kWh were in the battery. The percentage shown is not just not always accurate, it’s also subject to rounding and there is a buffer to take into account

 

[NLMGSAN]

Thanks. Yes, probably the temp will influence load losses. So it could have been worse in January. Btw, I have not used DC chargers with this car.
And indeed, percentages will be rough estimates. But if it was in fact 18.49% or 17.51%, it still wouldn't make a big difference.
I did check all the pictures I took of the overall power consumption in the dash. As I said, there are some gaps but they do represent the entire priod since having the car. I do get a slightly higher rate of 16.4 kwh/100 km. That still makes 7.3% load loss. Is that similar to yours?

 

[fnegroni]

Thanks. Yes, probably the temp will influence load losses. So it could have been worse in January. Btw, I have not used DC chargers with this car.
And indeed, percentages will be rough estimates. But if it was in fact 18.49% or 17.51%, it still wouldn't make a big difference.
I did check all the pictures I took of the overall power consumption in the dash. As I said, there are some gaps but they do represent the entire priod since having the car. I do get a slightly higher rate of 16.4 kwh/100 km. That still makes 7.3% load loss. Is that similar to yours?

I get 8% loss on average on a good AC charger, and 17% loss on a granny charger.

 

[DixieTGS]

I get 8% loss on average on a good AC charger, and 17% loss on a granny charger.

In a previous thread I think this was attributed to the fixed losses being a larger % of the total at lower powers which makes sense.

AC charging is not the most efficient especially above 3.6kW as the losses increase

This seems to contradict the above, or have I misunderstood?

 

[siteguru]

There's probably a tipping point ... power is related to the square of current so at some point the variable losses (related to current draw) will become more significant. I don't think that tipping point is as low as 3.6kW though.

 

[fnegroni]

In a previous thread I think this was attributed to the fixed losses being a larger % of the total at lower powers which makes sense.

This seems to contradict the above, or have I misunderstood?

Not really, it’s just that with a 3.6kW input I only lose 150-200W, with a 7.0kW input I lose 500W, which is more than double.
It might be down to rounding, but the cable at 7kW gets rather warm compared to 3.6kW

 

[NLMGSAN]

Maybe that explains it a bit: mine is a 3 phase cable 11 KW (most chargers only manage 10 kW), and it never felt warm or hot.