Drove a leaf today

Perhaps the question is "Does the chargepoint report kWh with or without any of the EVSE losses?"

The chargepoint station itself consumes some energy to run it's own computer and communications radio.

 

The charging station has no control or knowledge of the loss from converting AC to DC and the loss of charging the battery with DC. I guess those occurs in PiP. Previously, I thought AC to DC conversion took place in ChargePoint system.

If they bill the customers for the cost(electricity loss) of running the chargepoint station, they may face a law suit. Just like transmission loss from the power plant to the wall. Who end up getting charged for it? I shouldn't be paying for the loss of transmission from the power plant. I should pay for only what's delivered to me. But, there is delivery charge in every kWh I purchase so perhaps, the transmission loss is passed on to me....

 

I don't know of any ChargePoint stations that are charging by the kWh. The ones in Austin charge by the hour for non-subscribers or a flat rate for subscribers.

The quickcharge stations, which are DC and a Leaf can use, might charge by the kWh.

 

What is the source of that statement? How did they estimate the highly variable (temp) discharge loss? Just getting SOC is hard, getting discharge loss without a lot of external measurements is not something I see how any car could do.

 

Just to be clear, I was not talking about self-discharge loss. The loss of electricity as the battery sits unused.

I was talking about the loss (as heat) when the battery gets discharged. We know the usable capacity of the battery (PiP has 2.73 kWh usable). Dividing that by the actual EV miles and you get the electric mile efficiency. That includes the battery discharge loss, electric motor loss, mechanical loss, rolling loss, aero loss, etc...

 

Ok. Charging by hour makes that non-issue but the kWh displayed is still in question.

 

Is that what is displayed by the car?

The PiP at a full charge will have a "range" of usable kWh, its a distribution that depending on temp and charging profile as well as the actual battery pack. When quantifiying products its generally the "mean" of the distribution that is used. That is part of the problem with measuring loss. Sure you can presume its 2.73, but maybe today it was 2.8 or 2.6.

 

does the gas burned to warm the PiP somehow get included in the PiP's EV mile efficiency ?

 

PiP displays kWh in integer, only after it is consumed (not charged). I don't know how that got tracked and displayed -- which is why I was using general numbers and avoiding complexity associated with getting the exact numbers.

It takes about 3.1 kWh to charge and there is about 2.7 kWh (62% of 4.4 kWh) usable. There is about 15% charging loss. It will vary depending on the temp, voltage, SOC, etc.

To make things easier, shouldn't there be a general number for Volt and Leaf as well?

 

No. EV miles are not counted unless the gas engine is off.

 

But if it does generation then, do the resulting miles (since the battery gets some charge) count to EV miles?
Since its been documented the the PiP allows EV "stacking", I would think that indicated it happily counts EV miles no matter what the source of the charge if one play with the modes right. But what does it to if in EV mode when it needs the ICE for heat.. it has to effectively switch to HV mode, and then switch back after the heat is provided so it may be natually stacking?

 

I know of a couple there's one in a mall about two miles away from my parents' place.

 

IIRC most states do not allow charging per kwh except by a regulated utility, thus most charging stations bill by the hour. However, the charging station companies are trying to get the laws changed nation wide. Their systems are already setup to report kwh consumed. This consumption is measured from the charging station to the car, thus it includes all losses in the car. Of course it does not include any losses from the power plant to the charging stations since they would have no way of knowing that or measuring that.

Utility companies also have no way of measuring that, directly either. They are only allowed to charge per kwh delivered. But they can, in aggregate, measure/estimate losses and their rates reflect this.

Mike

 

Yes, in those rare cases I think they (EV miles charged by excess ICE/regen power) will be counted as EV miles. Gas consumption will go up for HV miles.

The opposite happens too. For example in EV BOOST when both the battery and gas are blended above 62 mph. I think those miles are counted as HV miles since the gas engine is running.

I think they both pretty much even out. What's important is to state the efficiency of both electric and gas miles. If one does a lot of EV Stacking, gas MPG will suck. If one uses EV BOOST a lot, electric MPGe or Wh/mi will suck.

 

so ... in the other thread you said I needed to count energy used to pre-condition the cabin as part of my MPGe electric.

How Many kWh in a Full Charge? | Page 2 | PriusChat

that sounds different than what you are suggesting in this thread.

do prius owners with an electric block heater count the kWh used in their MPG ?

 

Yes, if it is possible to count, then count them in. I would avoid being anal about it, like lower energy content in 10% Ethanol in gas, gas molecule loss during fill up in fumes, battery self-discharge, etc..

I have no idea if PiP adjust those miles by remembering the SOC between mode changes or partially crediting back the EV miles in the EV BOOST mode. You can Regen EV Stack in Volt if you switch back and forth to/from Mountain mode or HOLD mode. I am not anal about it as long as you state efficiency of both fuels.

Preheat using the grid power can consume 0.83 kWh (5 kW in 10 mins). That can power Volt for 2-3 miles so it is a sizable amount that should be counted.

 

I'm not so sure. Do we count the energy used to heat a garage and keep a car warmed in the vehicle's efficiency?

Like you state, it is a significant amount of consumption, so subtracting it out would raise my MPGe.

 

How about keep it simple. Just count whatever fuel that pump/plug into the car. Leave out anything external.

 

I agree, all the externals affect all cars but they aren't counted.

Alan.. Sent with Tapatalk 2

 

Motortrend already confirmed that. Volt's EV mode provides about the same power up to 30 mph. Beyond that speed, hybrid mode provides more power.