Question about Carwings data

[CRLeafSL]

I was looking through my Carwings data on the owners portal and I saw a section for how much power you have drawn charging your car and roughly the cost based on your electric rates. My question would be is this how much power the charger has pulled from the outlet or how much charge that the onboard charger has actually fed into the battery? I know there is a difference between how much is being pulled from the outlet versus how much actually gets into the battery is the reason I'm asking.

 

[rdhauser]

Don't have an answer for you but others have looked into this more than I and will, no doubt, weigh in. Tonight I've been looking at data for the last year from Carwings and from Blink. Carwings is about 15% less on kWh used for charge than Blink. Seems like a big difference to me. And, it's consistent through the year. I wonder (no data to back this up) if Carwings is using some algorithms to develop estimates from data sent in by the car.

 

[RegGuheert]

My question would be is this how much power the charger has pulled from the outlet or how much charge that the onboard charger has actually fed into the battery?

If you are discussing the "Electric Rate Simulation" data from Carwings, then I think it is neither of these things. I believe the number there is energy flowing out of the battery while driving. To be more exact, I believe that number is obtained by integrating the power flowing out of the battery while accelerating or cruising into one energy number and integrating the power flowing into the battery while regenerating into a second energy number and then subtracting the second energy from the first.

According to measurements made by NREL, the energy flowing into the battery is about 3% higher than that flowing out of the battery (at least for a new LEAF battery) and energy flowing from the wall for a full Level 2 charge is about 15% higher than energy flowing into the battery.

So in order to estimate the energy consumed from the wall you will need to multiply the energy on the "Electric Rate Simulation" page by a factor of 1.19. Since that is close to rdhauser's experience, I think that should get you into the ballpark. If you are charging with Level 1, the factor is quite a bit higher. It is probably on the order of 1.27.

Please note that Nissan only keeps that data around in CarWings for a couple of months. If you want the data for longer than that, you will need to download it as it becomes available.