Home Charging efficiency

Sandvinsd

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San Diego
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Air Grand Touring
Performing my first L2 charge at home. My ChargePoint flex is delivering 9.11 kW on the 40 amp circuit per the ChargePoint App so my EvSE is working well. The Lucid App appears to show the amount being received. Since it only provides 1 significant digit, I can’t get a real accurate read. It bounces between 8 and 9 kw so I am assuming that somewhere around 8.5 kw (+/- some number) is being delivered into the battery. Garage is cool, probably about 70. The electric loss at 8.5 being delivered would be about 6-7%. That is fine on a 240v outlet, but I can see how people might get “negative charging” on a 110v plug or at best, get just 1 or 2 kw per hour delivered.
 
I agree with this. Here are a couple of additional data points comparing home charging with the Lucid mobile cable to level 2 charging at work.

- Home - 9kW with a charge rate of 34 to 35 mi/hr
- Work - 6kW with a charge rate of 18 to 19 mi/hr

It is a lot hotter charging in the afternoon at work than in my garage (usually in the morning). But this implies that close 3kW are going to charging losses and battery cooling at work. There is no way that a 1.2kW 110V will keep up with that.
 
Performing my first L2 charge at home. My ChargePoint flex is delivering 9.11 kW on the 40 amp circuit per the ChargePoint App so my EvSE is working well. The Lucid App appears to show the amount being received. Since it only provides 1 significant digit, I can’t get a real accurate read. It bounces between 8 and 9 kw so I am assuming that somewhere around 8.5 kw (+/- some number) is being delivered into the battery. Garage is cool, probably about 70. The electric loss at 8.5 being delivered would be about 6-7%. That is fine on a 240v outlet, but I can see how people might get “negative charging” on a 110v plug or at best, get just 1 or 2 kw per hour delivered.
Did you get a red ring when charging/full? Paging @Archer
 
Getting 33-34 miles per hour in the garage, but I always think in kwh and not miles. It all depends on what number they are using to convert kw delivered into miles. Fans turn on and off during the charge which does consume poser. Currently based on what ChargePoint delivered and ‘miles‘ Lucid received, that number is 4.17 miles received per kw delivered. On a GT with 19” tires, should be using a 4.6 miles per kw calculation. That indicates about a 10% loss during the charge.
 
Did you get a red ring when charging/full? Paging @Archer
No red ring at this time. Not full yet. Still charging. It’s set for 80%. Will update when done.about 35’ left per the app. Since it is the weekend, I am on night rates so there was no delay when plugging in this morning. Will try overnight charging another day to see if I get any issues.
 
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Getting 33-34 miles per hour in the garage, but I always think in kwh and not miles. It all depends on what number they are using to convert kw delivered into miles. Fans turn on and off during the charge which does consume poser. Currently based on what ChargePoint delivered and ‘miles‘ Lucid received, that number is 4.17 miles received per kw delivered. On a GT with 19” tires, should be using a 4.6 miles per kw calculation. That indicates about a 10% loss during the charge.
IF Lucid were smart in their calculations they should be using thr historical average of your mi/kwh to show how much range you are getting, but I don't think they have changed it at this point yet.
 
IF Lucid were smart in their calculations they should be using thr historical average of your mi/kwh to show how much range you are getting, but I don't think they have changed it at this point yet.
Well my “historical average’ is 2.9 car is new. If they used that number, then am getting more kw into the car than ChargePoint is delivering! it’s making electricity while charging! 🤣
 
Have some data now that the car finished the charge. This is from an 80% fill to an 80% fill and driving 43 miles in between. The ChargePoint Flex delivered 17.49 kWh. Lucid app said it received 15. Car trip computer said it had consumed 16 kWh since the last charge and 14kWh while driving. The Lucid App doesn’t go into decimal points so it lost somewhere between 1.49 and 2.49 kWh during the charge or between 8.5% and 14.2% loss during charging. Large error bars, but 10% seems to be about right. My cost of electricity at the current TOU was $1.82 for those 17.49 kWh. I drove 43 miles between fills so the cost per mile driven was 4.2 cents. Even with the energy losses, much better than an ICE in CA.

For driving efficiencies (again large error bars since I only have a small amount of data from one data point). Car trip computer said I averaged 3.0 miles per KWh. 43/3.0 = 14.33. Car computer says 14 so that calculation is reasonable. Since last charge says 2.7 miles per kWh. 43/2.7 = 15.9. car says 16 so reasonable. Charge received 15 kWh per the app, so from that, 43 miles / 15 kWh = 2.87 miles per kWh received. Full battery would have driven 321 miles , or about 62% of the reported range. Take that with a very SMALL grain of salt. At this point it is just weak data with only 43 miles of spirited driving and much time sitting in the car with the power on programming different things.

For ACTUAL efficiency like I would calculate for an ICE, miles driven / energy delivered, 43 miles / 17.49 kWh = 2.49 miles per kWh delivered to the car. One can’t use this number to calculate range on a full charge, but is useful in comparing the EV efficiency in miles per kWh to an ICE in miles per gallon. it takes all the charging losses into account.

Again, one data point with very few miles and kW in the calculation so error bars are huge at this point.

As an aside, Lucid said the charge was complete, but ChargePoint was still ‘filling‘ the battery. The Lucid app said it was done and the charging port lights indicated as such. I had to stop the ChargePoint. The cable remains locked in the port even after I stopped the charge and until I wake the car which was new to me. I have always been able to remove the cable from the Leaf when the charge was done. Is there a setting that one can toggle in the car? I know the Leaf will allow you to lock the cable or not in the car software. Not aur3 if Lucid has that functionality.

and as for a “red light’ on the ChargePoint. No, everything was normal.
 
I agree with this. Here are a couple of additional data points comparing home charging with the Lucid mobile cable to level 2 charging at work.

- Home - 9kW with a charge rate of 34 to 35 mi/hr
- Work - 6kW with a charge rate of 18 to 19 mi/hr
Sounds like your Work charging setup is only capable of 6.6kW, which is pretty common for older installations.
 
Charging losses come in roughly three flavors:

A fixed loss (C) of several hundred watts or so to power up the car's charging computer/electronics, invariant with charging current
A linear loss (B) from diode drops, etc, varying directly with charging current
A square-law loss (A) from wire and circuit resistance, battery resistance, battery cooling, etc varying with the square of the charging current

Roughly Loss(x) ~ Ax^2 + Bx + C where x is charging current

Sounds like C is close to 1kW on the Air, so little useful charging power is left when using 1.4kW 120V.
 
The car has to be unlocked to remove the charge cable.
With a recent update I think 1.2.1 you don't actually have to unlock the car to unplug the charge cable. If it detects a key, it will unlock the charge point without necessarily unlocking the doors. It will most likely unlock the doors anyways, but the charge lock is independent of the door locks.
 
With a recent update I think 1.2.1 you don't actually have to unlock the car to unplug the charge cable. If it detects a key, it will unlock the charge point without necessarily unlocking the doors. It will most likely unlock the doors anyways, but the charge lock is independent of the door locks.
The manual does say that the doors have to be unlocked but it also could be that because of the key fob/mobile key issues that my car has, I have to unlock the doors in order to disconnect. If everything is working correctly, this distinction makes very little difference.
 
You can manually unplug the charge cable under all circumstances by pulling up the lever under the frunk hood. For emergency but needs to be known.
Page 146 of the manual.
 
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You can manually unplug the charge cable under all circumstances by pulling up the lever under the frunk hood. For emergency but needs to be known.
Page 146 of the manual.
Guess I need to read the entire manual. I’m Old school and like to read hard copies which is why I have not read it yet.
 
Second charge at home. This one overnight. for the actual efficiency,

charge 1: 17.49 kWh delivered 43 miles driven = 2.46 miles /kWh
charge 2: 32.18 kWh delivered, 80 miles driven = 2.49 miles /kwh
Life of car = 123 miles / 49.67 kWh delivered = 2.47 miles per kWh

Could not see the actual kWh received. Can calculate using battery percentage. Battery was at 56% to begin charge 2 , ended at 80% = 24% x 112 kWh battery = 26.88 kWh received

Charge 2: 5.3 kWh “extra“ kWh delivered but not received = 16.5% loss seems very high
Charge 1 loss, using the more generous numbers was 1.49 extra = 8.5% loss.

This is a TON of vampire drain on this second charge.. More than just heat loss during charging.

in calculating driving range using kWh received over the two charges.
charge 1: 16 kWh
charge 2: 26,88 kWh
tofal = 42.88 kWh consumed to drive 123 miles = 2.86 miles per kWh x 112 battery = 321 estimated real range
321 miles real range / 516 EPA = 62% of EPA range.

I’m hoping this gets better over time. Again, I am probably driving more spirited than I will on trips. With this number, it means I will have to stop every 200 miles or so to recharge. Was I expecting this number? No. I was hoping for something higher, but is the reason why I have repeatedly said, I need a car with 500 miles / 1000 km range to use as a trip car. If I purchased a car with 300 miles range = 186 miles of real life range and in going from 20-80% between charges means I would be stopping every 112 miles.
 
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