Is the car keeping my garage warm?

[Vinnigan]

I can't really find this being talked about anywhere, but with ICE cars, my attached garage always equalizes to ambient outside temperature +/- 10 degrees overnight.

Since taking delivery my Y, I've noticed that the garage now stays at 72 degrees F +/- 5 degrees, even as the outside temps dropped to high 40s.

The car is plugged in 24/7 and I haven't tried letting the car sit overnight unplugged. But does the car maintain a very specific temperature when plugged in? That would explain why the ambient temperature around the car stays almost fixed 24/7.

I've read hours and hours of threads since deciding to purchase the car but have never seen this being talked about. I'm just curious to understand how things work.

P.S. No sentry or cabin overheat protection. Car isn't locked though.

 

[whisperingshad]

charging the car warms up alot.

 

[jcanoe]

Di you leave Sentry mode turned on when parked at home inside your garage? This causes the Tesla Model Y to remain in Standby mode and will consume ~230W, computers and other systems stay powered on. This could account for some of the garage temperature increase. LPTT: Set Sentry mode to be off when parked at your home location, especially if you park inside a garage. The Tesla Model Y will enter Sleep mode and will consume much less power ~25W versus ~230W when in Standby Mode. If you park outside you can still have Sentry mode set to be off and the Tesla Model Y can still be set to lock with the vehicle alarm active (but not Sentry mode.) If you must park in a location where you are concerned about damage and theft then leave Sentry mode set to be on when parked.

Another factor is that you have introduced a 4400 lb vehicle with an 1100 lb battery into the garage environment. That battery acts like a large heat sink, i.e. it stores thermal energy for a number of hours. The heat from the battery slowly dissipates into the garage space. (In an ICE vehicle you arrive home with a warm engine block and radiator, coolant. There is also some warming of the garage but maybe not as much as with the Tesla battery due to the larger mass.) Charging powers on the Tesla vehicle's systems and there is some warming of the battery that takes place while charging; Depending on how many hours you charge each day would determine what garage warming would take place (probably minimal) as we are not talking about Supercharging.

 

[Vinnigan]

charging the car warms up alot.

The vast majority of the time it’s not actively charging though, and I made sure not to check the app so the car goes to sleep especially overnight. It took a while to wake the car up when I checked in the morning so I’m pretty sure it did go to sleep, but both the inside and outside temps were still at 72f.

Not a big deal of course. Just interesting. Maybe I’m just misremembering how my garage actually maintains temps.

 

[Vinnigan]

Di you leave Sentry mode turned on when parked at home inside your garage? This causes the Tesla Model Y to remain in Standby mode and will consume ~230W, computers and other systems stay powered on. This could account for some of the garage temperature increase. LPTT: Set Sentry mode to be off when parked at your home location, especially if you park inside a garage. The Tesla Model Y will enter Sleep mode and will consume much less power ~25W versus ~230W when in Standby Mode. If you park outside you can still have Sentry mode set to be off and the Tesla Model Y can still be set to lock with the vehicle alarm active (but not Sentry mode.) If you must park in a location where you are concerned about damage and theft then leave Sentry mode set to be on when parked.

Another factor is that you have introduced a 4400 lb vehicle with an 1100 lb battery into the garage environment. That battery acts like a large heat sink, i.e. it stores thermal energy for a number of hours. The heat from the battery slowly dissipates into the garage space. (In an ICE vehicle you arrive home with a warm engine block and radiator, coolant. There is also some warming of the garage but maybe not as much as with the Tesla battery due to the larger mass.)

Sentry mode is set to be off when at home, but everything else you said makes sense!

 

[zoomer0056]

The car is plugged in 24/7 and I haven't tried letting the car sit overnight unplugged.

I don't know, but all the info you give says yes. There is absolutely no need (but i have to ask, why do you) to keep your car plugged in just for daily use. Try unplugging after your charge, see what happens.

 

[jjrandorin]

I don't know, but all the info you give says yes. There is absolutely no need (but i have to ask, why do you) to keep your car plugged in just for daily use. Try unplugging after your charge, see what happens.

Because thats what the information directly from Tesla says to do, and there really isnt any reason NOT to, either.

 

[zoomer0056]

Because thats what the information directly from Tesla says to do, and there really isnt any reason NOT to, either.

Are you answering for the OP? Well ... I can see that as a good answer, because that's ecactly whats in the manual.. However, because Tesla says so doesn't mean it's good. Why, just last month Tesla was advising up to 90% daily charge. Now they advise up to 80%. I would trust TMC experts on batteries over Tesla. Don't get me wrong, I think Tesla is awesome ... and so is TMC.

 

[dakhlkt22]

If you activate TeslaFi or Tessie apps, you can verify if it's actually sleeping.

 

[jjrandorin]

Well ... I can see that as a good answer. However, because Tesla says so doesn't mean it's good. Why, just last month Tesla was advising up to 90% daily charge. Now they advise up to 80%. I would trust TMC experts on batteries over Tesla. Don't get me wrong, I think Tesla is awesome ... and so is TMC.

You wont find anyone on TMC that has any knowledge around this saying that someone needs to keep the car unplugged for any reason other than perhaps an approaching storm.

Just like it doesnt have to be plugged in, there isnt any reason not to, either. Its more convenient to leave it plugged in if you have home charging (for most) since you dont have to remember to do it if you decide to change your charging percentage.

You said there is absolutely no need to keep it plugged in if one doesnt want to, and thats correct. Its just that its also correct there isnt any reason to NOT plug it in, and the reason many people will plug it in is because it is direction given specifically in Teslas manual to do so.

Im not getting into the charging percentage thing, because those recommendations are brand new from Tesla, and seem to be vehicle dependent (my model 3 and model Y have different recommendations on that front) so I am not sure whats driving those recommendations, nor why they are making them.

 

[Vinnigan]

I don't know, but all the info you give says yes. There is absolutely no need (but i have to ask, why do you) to keep your car plugged in just for daily use. Try unplugging after your charge, see what happens.

I'm a certified newbie right now so definitely take my words with a grain of salt, but I've tried what I can to research deep and wide on understanding battery engineering and the chemistry of lithium ion batteries.

It's my learned understanding that the chemical composition is most at the equilibrium state at 50% SoC, and the charging/discharging of a li-ion battery is basically a chemical reaction that occurs across the cathode and anode via the electrolyte layer. This means that the closer to the equilibrium point, the less violent the the chemical reactions, and the less stressed the batteries are.

So, I keep my SoC at 55% unless I need to go somewhere, and I keep it plugged in to minimize the un-needed chemical reactions in the pack.

Again, this is unless I need to use it, in which case I've charged up to 90% for a day trip and I've supercharged. But if I don't need to use it, I am happier keeping the pack in the least chemically stressed state. I've shifted my mindset of a BEV ownership from that of a vehicle as traditionally thought of in an ICE car, to a large, unpluggable electrical household appliance.

I am likely wrong in some of my understanding, but it's where my head is at currently!

 

[bruce4000]

I leave my car plugged in all the time and doesn’t noticeably affect the temperature. If you drive a lot everyday and therefore charge a lot I could see it warming the garage from the electrical resistance loses. The Tesla computer doesn’t draw a lot more than a 100 W lightbulb so not that much heat: also depends on how well your garage is insulated. What I really noticed this summer was when it was in the low 80’s outside, when I drive my ice car and park it back in the garage, later it was over 100 deg in the garage from all the engine and coolant- ice cars are only 20 percent efficient heat engines.

 

[Vinnigan]

I leave my car plugged in all the time and doesn’t noticeably affect the temperature. If you drive a lot everyday and therefore charge a lot I could see it warming the garage from the electrical resistance loses. The Tesla computer doesn’t draw a lot more than a 100 W lightbulb so not that much heat: also depends on how well your garage is insulated. What I really noticed this summer was when it was in the low 80’s outside, when I drive my ice car and park it back in the garage, later it was over 100 deg in the garage from all the engine and coolant- ice cars are only 20 percent efficient heat engines.

Totally. In my attempt to understand this behavior the last week, I’ve also noticed that our other ICE car in the garage gives out A TON of heat after parking.

I guess I never paid attention to any of this before during my ICE ownership lol.

 

[zoomer0056]

So, I keep my SoC at 55% unless I need to go somewhere, and I keep it plugged in to minimize the un-needed chemical reactions in the pack.

Yes, from reading TMC, I also like to average my car SOC around 50%. For my daily needs the car is charged to 55%. My car, at most will loose 1% in 24 hours. I have seen that several times when away from home for a week or more. For daily driving, the car does not sit for 24 hours and I rarely see 1% drainage between daily drive/charge. I've never left the car plugged in when not charging. Two years, 13k miles and 3.8% battery degredation per the Tessie app.

 

[father_of_6]

I have a hard time believing that the car is making a bunch of heat. Might there be some windows in the garage that are just now getting the right angle of sun to produce a greenhouse effect?

 

[jjrandorin]

I have a hard time believing that the car is making a bunch of heat. Might there be some windows in the garage that are just now getting the right angle of sun to produce a greenhouse effect?

My Model 3 warms up my garage about the same amount that my BMW 335i Msport did, doing the same commute to work (roughly 40 miles each way). My feeling (which is just that, a feeling) is more along the lines of what @jcanoe said, large battery putting off heat.

I have always thought it was a lower temperature than my ICE vehicle, but for longer (because the battery is large). I havent given it more thought than "my garage feels the same as it did when I commuted in my BMWs".

 

[Vinnigan]

I've never left the car plugged in when not charging. Two years, 13k miles and 3.8% battery degredation per the Tessie app.

Cool. Do you hold a belief that keeping the car plugged in damages the battery? If so, please elaborate.

Otherwise, I’ve given you the explanation of my logic in good faith, and I hope you realize that the idea behind what you’re saying is basically identical to someone else saying “I charge to 100% all the time and I have very little degradation”.

I’m not advocating anyone else plug in their car in this thread.

All this is especially in light of the fact that battery degradation has nothing to do with my original post.

 

[Big Dog]

Because thats what the information directly from Tesla says to do, and there really isnt any reason NOT to, either.

We have 2 Tesla's and only one charger.....That said, don't drive either much, so only plug in when one of them gets down to ~30%.

 

[father_of_6]

My understanding is that if it's plugged in, the car will use AC power for preconditioning the battery and/or cabin. It also means you don't have to go out and plug it in if you want to bump the state of charge up on short notice.

Other than unplugging due to an electrical storm, there aren't any reasons I know of *not* to plug it in all the time, and there are several reasons *to* plug it in all the time, including just building the habit so you don't forget to charge one day.

I usually plug in at the last drive of each day, unless the battery is already within a few percent of the target and I know for sure I'm not going anywhere far in the morning.

 

[zoomer0056]

Cool. Do you hold a belief that keeping the car plugged in damages the battery? If so, please elaborate.

It's just not necessary to keep the car plugged in. One benefit, pointed out by @father_of_6 , would bf using house current for batteru conditioning instead of the battery. But I believe thats only if there is a departure scheduled.

“I charge to 100% all the time and I have very little degradation”

Everybody knows charging to 100% and letting to car sit is bad for the battery.