Charger Efficiency

[rfguy]

Took delivery of 2017 Chevy Bolt Premier with regular charger provided with car. The car had 34 miles on it at delivery and I believe the dealer had never charged as it was at about 60% when we picked it up on Aug 3. We gave it a full charge and now have 382 miles on it with an average of 3.8 miles/Kwh according to dash readout. Assuming this to be correct I computed that we have used a total of 101 Kwh of energy. I realize it may have never been fully charged at delivery but here is my question. Does anyone know what the efficiency of the factory level 1 charger is? How much Kwh does it take to put a kwh of energy in the car? I received my light bill and using last year and the past 2 months of usage as metrics I estimate we have used 310Kwh to charge the car which is about 30% efficient. Sounds low to me should be up around 60-70%.

Has anyone researched this? My next thing is to put a meter on the circuit. and measure what the energy usage really is. Are the level 2 chargers more efficient? I don't really need that fast of a charger but will go for it if there is money to save on efficiency.

Thanks

 

[grestep5621]

Level 2 chargers are slightly more efficient.
Once you get a meter on the EVSE on a dedicated line, I think you will see better efficiency.
The numbers you are seeing are way low.

 

[DucRider]

The charger is in the car and handles both L1 (120V) and L2 (240V).
This diagram shows Level 2. L1 is the same but feeds 120 V to the charger.

L2 is slightly more efficient:

Ambient temps also influence efficiency.


Much more detail in the full report:
https://www.veic.org/docs/Transportation/20130320-EVT-NRA-Final-Report.pdf

 

[WetEV]

Much more detail in the full report: 20130320-EVT-NRA-Final-Report

One point of concern with this study is:

All vehicle data used in this study was from General Motors Chevrolet Volts of the same model year.

The efficiency difference is larger at higher charging rates as are common with most BEVs such as the Bolt.

The conclusion that a home L2 station will not save enough in electric power to pay for the cost of an L2 is correct for most people.

The real reason to have home L2 is convenience.

 

[rfguy]

Thank you to all for great info and link.

Russ