Speak EV - Electric Car Forums banner
1 - 11 of 11 Posts

·
Registered
Joined
·
196 Posts
Discussion Starter · #1 ·
It appears that the e-Niro has the least percentage of charging loss amongst the currently available EVs.


Really surprised at the 25% loss with the M3. This would make the e-Niro the most efficient vehicle in terms of miles per actual kWh taken from the EVSE.
 

·
Registered
Kia Soul EV 2020
Joined
·
2,632 Posts
It appears that the e-Niro has the least percentage of charging loss amongst the currently available EVs.


Really surprised at the 25% loss with the M3. This would make the e-Niro the most efficient vehicle in terms of miles per actual kWh taken from the EVSE.
I'm not sure if it is the same study, but Bjorn Nyland had a few "not so kind" words about the results of a similar study. If I remember correctly, his estimation was that the TM3 had about 12% charging loss. TBH, that was one of his videos, that I did not like because he was trying too hard to make Tesla look good, and it was obvious. Usually, I am a big fan of his vids.
 

·
Registered
Joined
·
1,894 Posts
It appears that the e-Niro has the least percentage of charging loss amongst the currently available EVs.


Really surprised at the 25% loss with the M3. This would make the e-Niro the most efficient vehicle in terms of miles per actual kWh taken from the EVSE.
Depending how they measured it, they could be including the "vampire" loss from the M3 as it tends to run some onboard computers when dormant more than other cars. Sentry mode, of course, is especially heavy if that is used.
 

·
Registered
Kia e-Niro 4 MY20, Zoe Z.E.50 GT Line
Joined
·
1,313 Posts
Just how much power a Tesla can use when parked has been a recurring issue iirc. The Niro doesn’t seem to noticeably lose HV battery charge when parked up. Although the Tesla drivetrain efficiency is supposed to be really good. The overall car efficiency is pretty poor.
 

·
Registered
EU base model with heat pump Sept '18
Joined
·
571 Posts
So, the only place where the EV measures power precisely on our Kona/Niro is at the battery pack. The dash efficiency/consumption reading is the net power drawn from the battery v.s distance traveled, including all use of power in the car such as HVAC.

Obviously the mode of charging makes all the difference here to overall efficiency, which the article seems to ignore. The single-phase on-board charger on the Kona (and presumably the Niro) is rated at 91% efficiency but that would certainly decrease at lower power levels. I'm pretty sure the dash power reading while charging is the DC output of the OBC, not the input.

DC charging however is normally measured and billed on the DC side so the vendor absorbs the power conversion losses.

There's also associated use of power while charging, for overheads, climate preconditioning and charging the aux battery.

The average battery cycle loss can be evaluated by the battery's "odometers" (CEC and CED) and is around 96% overall on my Kona. You can estimate either charging or discharging efficiency individually as the square root of that value, i.e. 98%.

So, it's somewhat complicated to assess overall efficiency and it can be quite variable. When I've tried to evaluate this I recall I've seen a range anywhere from the low 80s to perhaps the low 90s as a percent of charging energy. All I can suggest in summary is that you'll probably show better overall efficiency when running on energy based on DC charging.
 

·
Registered
Joined
·
196 Posts
Discussion Starter · #8 ·
DC charging however is normally measured and billed on the DC side so the vendor absorbs the power conversion losses.
B Nyland found that there are charging losses with DC chargers and there was a difference in what the car registered and what was billed by the vendor.

 

·
Registered
EU base model with heat pump Sept '18
Joined
·
571 Posts
The power conversion losses I'm referring to are those in the EVSE itself. Overhead losses in the car will account for a difference between what the EVSE supplies as DC and what is measured and displayed as charging power to the battery. Also, it's possible that some DC EVSEs bill on AC power but those I've researched do not, or can only do that if the EVSE owner specifies that option.
 

·
Registered
Joined
·
298 Posts
It appears that the e-Niro has the least percentage of charging loss amongst the currently available EVs.


Really surprised at the 25% loss with the M3. This would make the e-Niro the most efficient vehicle in terms of miles per actual kWh taken from the EVSE.
On our First Edition, 15% charging loss is typical on the 7kW home charger, e.g. most recent charge: 19kWh ex charger, 17.0kWh ex onboard charger (recorded by BMS, read through OBD2/dongle), 16.1kWh increase in battery charge. N.B. calculating the kWh increase/decrease in the battery is not straightforward, as the percentage SOC relates to amp-hours (180Ah total) and the voltage drops from around 405V at 100% to maybe 320V down at the bottom (never ventured that low). Rapids typically 12-15%, granny lead 25%.
 
1 - 11 of 11 Posts
Top