Tested: Preconditioning actually helps (duh) in cold weather driving!

[Bogeyman]

Thanks for the video. Based on advice from the Chelsea SC, I have been turning on the cabin temp in my R1S about 30 minutes before leaving on our colder NH days. I have also found that the minimal power use for preconditioning (about 1%) has helped with range efficiency (kWh.mi).

Couple of questions - My tire pressures increase about 3 psi once I have been driving and the tires warm up. I noticed in your screen shot in the R1T that your tire pressures were low, with right rear being in the red zone. Do you have a problem with wildly-fluctuating tire pressures given the extreme temperatures and altitude? What do you target for your tire pressure (Lower in winter?)?

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[R.I.P.]

Thanks for the video. Based on advice from the Chelsea SC, I have been turning on the cabin temp in my R1S about 30 minutes before leaving on our colder NH days. I have also found that the minimal power use for preconditioning (about 1%) has helped with range efficiency (kWh.mi).

Couple of questions - My tire pressures increase about 3 psi once I have been driving and the tires warm up. I noticed in your screen shot in the R1T that your tire pressures were low, with right rear being in the red zone. Do you have a problem with wildly-fluctuating tire pressures given the extreme temperatures and altitude? What do you target for your tire pressure (Lower in winter?)?

Cold air contracts, lowering your tire pressures in the winter. It is important to add a little bit of air to bring them back up to rated pressure or maybe one pound over in the winter to maintain your economy.

 

[R.I.P.]

I have a question. It's 7 degrees F this morning. I'll probably want to use battery preconditioning before I drive. I have four motors. The way I understand it, heat from the motors is used to heat the battery. This can be done when the car isn't moving. So, are the motors actually spinning in "neutral" or are they magnetically locked or something so they don't spin. Did I miss the memo on this?

Yes, you definitely want to precondition. No, the motors do not spin. Electric motors have windings in them, very similar to an electric heating element. The vehicle simply runs current through these windings without moving the motors to create heat.

 

[Rivian Head]

Something must be wrong with my rig, because I have pre conditioned 3 times now, and each session has ended up with 47 percent range reduction and roughly a 1.19-1.31 rate.

Hmm
Same here. I got 1.4 today driving 10 deg weather for 40 min after preconditioning

 

[jpadz41]

i appreciate you putting together this video. it's really helpful to see some actual numbers (temp of battery, motors, minutes into a trip) correlate to real world efficiency.

i had been noticing a non-trivial decline in efficiency since late fall/early winter and i wasn't sold it was the cooler weather combined with never conditioning but now i feel very convinced that's exactly the case.

thanks again for this content.

 

[MWB]

Hmm
Same here. I got 1.4 today driving 10 deg weather for 40 min after preconditioning

Have you guys tried using the trip meter to measure efficiency? I've found the other gauge to be squirrely even in consistently mild weather comparing the same routes. If you reset the trip meter (Settings > About > Click on Trip A or Trip B > Reset), it should give you more accurate efficiency information.

Also, when you are scheduling the climate conditioning, do you have it plugged in and have you selected "pull from charger to maintain range"? R.I.P.'s recommendation for increasing tire pressure to optimal level in the cold would be important as well.

 

[md2023]

IMO pre conditioning the battery is more about getting the most range when setting off. I don't know if I'd bother on short trips.. but maybe I'm wrong.

Yes, agreed. But what I am most interested in, is when I am not plugged in. Does it help to warm up the battery/cabin. How does it impact range and is there some over/under on miles when it is worth it.
One challenge is taking the T on medium range ski trips where I don't have access to a charger near by (apx 80 miles each way).

 

[sub]

My vehicle must be broken.

Timed preconditioning has failed to activate 6 out of the 8 times I have tried to use it.

Both the app the climate page on car's screen show the next time it plans to activate, but it doesn't. I wonder if they've gotten so aggressive on The vampire drain complaints that the preconditioning timer can't wake the vehicle when it is asleep.

 

[WorldComposting]

Just watched and great comparison.
Quick question do you have the same tires on both vehicles? Also is that tire seems low or is it because you have on snow tires?

 

[dleewla]

haven't been able to get Scheduled Drive, tried soft/hard reset and sleep cycle. opened a service ticket but not sure what they can.

 

[FlightDoc]

Am I missing the "leaving in 30 min" button? I don't live on a set schedule. Just warming cabins seems to do nothing for battery warming. Seems like an ass-pain to set the weekly schedule each day.

 

[kuau]

How long should one precondition for? Is there a "sweet" spot in terms of time?

 

[Jayhawkeye]

I would assume no more than 30.

How long should one precondition for? Is there a "sweet" spot in terms of time?

 

[Herb]

Right. To me its a no brainer to pre-condition if plugged in. But how about when not? How does it impact range and is there some over/under on miles when it is worth it.

I have a question. It's 7 degrees F this morning. I'll probably want to use battery preconditioning before I drive. I have four motors. The way I understand it, heat from the motors is used to heat the battery. This can be done when the car isn't moving. So, are the motors actually spinning in "neutral" or are they magnetically locked or something so they don't spin. Did I miss the memo on this?

IMO pre conditioning the battery is more about getting the most range when setting off. I don't know if I'd bother on short trips.. but maybe I'm wrong.

I'd say it depends: consider that when taking the energy for pre-conditioning into account it's not straight forward. In my case (DM Max), with outside temp near zero, my garage is near freezing (33' right now). On my 5 mile drive to work, I get about 2m/kWh, but I would have spent a few kWh pre-heating the cabin and battery. I realize this might be an extreme example, but for my short drive, preconditioning may not save any energy. Spinning this further, without preconditioning and after 5 miles, the battery reaches equilibrium temperature anyways. This would mean that preconditioning never reduces total energy consumed, it just shifts it from battery to charger and basically buys a few miles of range. This is for DM max setup, the equation is apparently different for QM that need much more time to heat the battery

 

[Herb]

How long should one precondition for? Is there a "sweet" spot in terms of time?

You set the departure time, not a preheat time period. If find that I can set a fictious departure time that is at least 15 minutes later than my actual departure time and the cabin is already at 68 (parked in a 33' garage) and the battery warm enough to return 2m/kWh near zero outside temp. This is for DM Performance, I think QM will take longer to preheat the battery. Not sure if Rivian took that physical difference into consideration when rolling this feature out.

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