Preconditioning Observations

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I have preconditioned with the included level 1 unit many times and on colder days it will end up using a few percent of the battery. I never see this when I use my level 2 unit.
 
The preconditioning function for the I3 is somewhat complicated, from what I'm seeing you can engage it three ways:

1) Set it in the setting menu while in the car

2) Program it with a departure time on I Remote

3) Select to immediate Pre-heating via I Remote

What puzzled me is I had all these function off and noticed the fan on while the car was parked with no charging cord plugged in.

Regardless of all these function - one thing for sure I do not want any preheating of the car while its unplugged unless i call it up.

Any comments would be appreciated

Thanks

Mike
 
Depending on what your driving was like, the car might just be cooling itself off, similar to how on an ICE, the cooling fan can come on when the car is not running after then end of a run. This is probably more likely on the REx than the BEV, but I think, could happen with either. The REx supposedly will run when the car is off IF the battery level is critical to bring it back up some.
 
Jim,

I'm sorry I was not clear its the fan in the A/C that was running un-attended it was around 59 degrees here today!

Thanks

Mike
 
jadnashuanh said:
As some of you may remember, I installed a volt/amp meter on the lines feeding my EVSE about a month ago.

It was warmer then, and I'd mentioned that preconditioning on a fully charged battery was using about 12A at 245vac. Well, it was colder this morning, and when I went to disconnect the cord, I noticed that it was cycling between about 12A and nearly 19A. So, since power=volts*amps, when it was warmer (but still needed heating), at 12A*245vac, it was using 2940Watts; 19A*245vac, it was drawing 4655Watts! ...
..

This is interesting...

I am on the PG&E (US/California electricity supplier) EV-A rate plan in which the KWh's are charged at different rates during different times of the day. The Level II charge for the car is set to occur at night - the cheapest time, of course.

But if I precondition it for the departure time - 7:30AM - that puts that daily 4.655 Watt preconditioning (2.35 KWh if preconditioning for 1/2 hour, say 20 work days per month = 47KWh) into the more expensive mid-tier time slot.

That leads me to think I am better off accepting the range-distance hit since I do not need the full range in any given day.

Is my thought train valid?

Of course, in the end, we are talking about chicken-feed dollar amounts since KWh's are charged at $.40, $.21, $.09 at Peak, Mid, and Off-peak, respectively.
 
I suspect that the hit is less than you think. In rely cold conditions (under 20 degrees) it might be 20 minutes or do to prevent condition. At 40 or 45 degrees, I don't think it it would take more than 15 minutes, and it's probably not drawing at max rate for all of that.
 
I think it will really depend a lot on the ambient temperature when you tell it to precondition. My observation was with the ambient around 30-degrees F. It's been quite cold this week here, but I've not checked. Maybe tomorrow.

FWIW, I just had my KLE replaced, and with the cold weather, I was seeing essentially the full charge rate regardless - IOW, for me, at this location, with the way I drive it, I saw no charging degradation with the old software or changes in charging with the new stuff (so far). The vast majority of my trips are short, so the various parts probably haven't come up to a temperature where the logic would start to restrict the charge in the first place. People that live where it is warmer or take longer trips are where that issue is more likely to occur. When the car was sitting in the service bay at probably 70-degrees during the day, I happened to check my app, and it said 71-miles max range with the current charge state. After moving it outside and sitting for maybe 1/2-hour at temperatures in the teens (F), it dropped to about 54-miles. I attribute that entirely to the ambient temperature. Now, I live within walking distance of the dealership (in fact, walked there to pick up the car while I was offered a loaner, I didn't have a need), so I didn't drive it much and did not really notice any changes resulting from the new software. Over the next week or so, I'll have more opportunity to check things out. WHen you take into consideration all of the fees (account charges, infrastructure and delivery, actual cost of production of the electricity), my cost/Kw is about $0.18, with no cost effective off-peak use to lower cost, so I don't worry about when I plug it in.

One last thing...once the preconditioning has attained your desired cabin temperature (and whatever else it is conditioning), it doesn't take as much to maintain that temperature as it does running max out getting there. WHere I would tend to see 12-20A for awhile, if I went back just before leaving after it was just maintaining, it had dropped to about 5A or so. I put the meter in more as a 'it would be kind of neat', not as something I religiously monitor and it has no recording capabilities. I thought it might help to alert me to some long-term battery issue or other problem that might not be noticeable otherwise.
 
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