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Excessive vampire drain in cold
- Thread starter camalaio
- Start date
AlanSubie4Life
Efficiency Obsessed Member
You did not count (add back in) the precondition usage! (Was probably 16+km not 12km, in reality, due to warming.)
And really hard to say on your drive without trip meter info - could have been all downhill!
Lots of missing data makes impossible to assess.
Really hard to say. My point was that part that is counted as vampire is not.
You would have to experiment. Just leave the car sitting for another day or two and compare each day (assuming temps are the same). No driving allowed.
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Sorry, I missed that. And thanks for the reminder that Cabin overheat is limited in time. But I suspect a lot of folks are looking at "nightly" loss after driving it that day.
Don't get me wrong there might be some folks here that have legit concerns over degradation.
But you do need to be careful of what you are looking at.
Lets say you get home, maybe even after stopping at a supercharger and the battery is all toasty warm.
Then you park overnight (outside or not) but in a cold environment.
The battery could read a lot lower by morning but that isn't "vampire loss".
If you reheated the battery back to the temperature you parked it at it would return to the same miles you parked at (or close to it).
This is why the first day of measuring "vampire loss" is usually larger and not an accurate measure. To really know loss you need at least 2 days (ignoring the 1st day drop) and a fairly steady temperature. Now you compare the battery in the same state to the same state on the 2nd day. There are so many variables when you "park it" and what the battery does over the first 24 hours.
If the temperature dips to much the battery will report that it has significant "loss" with a "snow flake". But again, that is not lost and will recover when warmed up.
A good indicator of cooling is looking at regen limit. If you parked with full regen and looked in the morning and had no regen then your battery cooled quite a bit and might show more loss than you'd like to see.
Also know that the higher your state of charge the quicker you will see impacted regen from cooling.
It is somewhat downhill but I know I typically do no better than 50% efficiency even then because of the stop-go. With that said, you're right, there's a lot of information missing and I did not add back preconditioning. I still think there was a bigger loss on a cold night parked outside than when I leave my car in my heated garage. I just can't quantify it properly. I was trying to let camalaio know he's not alone
I wonder if I could do better logging with TeslaLogger instead of TeslaFi, coupled with ScanMyTesla which I already have. I'm tempted to switch but the manual work to set it up has prevented me so far.
So, to return back to the OP, he must find a way to look at battery percentage without waking up his car. Either with the iPhone widgets (I have an Android so I don't know that) or by looking at TeslaFi instead of the Tesla App/the car screen. Then let the car sit for a couple of days in a row... Eager to know the results.
Good point.
And along that line of thinking if you charge daily to 90% when it's cold out you'll average a lot less regen than if you charge to say 70-80% daily.
Exactly. And now our turn to beg you for all the details you left out and re-read your post 20 time to see if anything there. No thanks.
I won't say I know every thread, but what I've seen:
1) Imprecise data leads to exaggeration
2) The large drains come from driving the car and use of HVAC (heading/cooling). Just "a little bit wasn't worth mentioning".
3) Posters are very defensive and ungrateful when confronted about their perception.
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That’s an excellent Theory.
And it does appear based on other posts the 12V batteries don’t have the longest life span.
Sure would be nice to know how much 12V charging is going on. I wonder if the CANBus scanner apps can get that.
Check all of your settings, I noticed after a firmware update that some of my settings I normal have off were on again, “Cabin overheat protection” and “Keep Climate On” those were on when I always keep them off, also when away and parked somewhere turn off Data Sharing as well.
Shouldn’t lose anything in 12 hours or maybe 1 mile. The Obvious ones Sentry mode, Teslafi, summon and Dashcam will get ya.
ScanMyTesla app will show all voltages and drains as well as the 12 volt battery.
Fred
Shouldn’t lose anything in 12 hours or maybe 1 mile. The Obvious ones Sentry mode, Teslafi, summon and Dashcam will get ya.
ScanMyTesla app will show all voltages and drains as well as the 12 volt battery.
Fred
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Hi Fred. My sleep settings in Teslafi make for no drain. I’m going to check COH and keep climate on. Smart Summon standby is off. Thanks for the tip.
I couldn’t figure out the sleep setting in Teslafi so I got rid of it completely. Also you can have A Better Route Planner log into the car as well. Make sure this is also disconnected.
And say No to both in Data Sharing when you do your test.
Fred
Sorry for not following up yet, took a break from forums.
Some interesting new data/anecdotes. I realise this is all fairly imprecise for now.
Maybe given the above, the state of the BMS has been completely whack (or perhaps it's indicating some non-ideal scenario inside the pack). I know one thing I'm struggling with is that the trip estimator is egregiously optimistic -- for longer trip durations, it normally expects that I do 20% "more efficient" even when I stay below the speed limit and have climate control completely off. Using climate predictably makes it worse. We're fairly close to ABRP estimates though, within 1% mostly. Not sure if the Tesla trip planner is normally this bad, folks on this forum usually say it's pretty accurate (and it is for us in summer). Might be entirely unrelated.
Android, unfortunately. As for cell service, I'm not really sure what's up. It's full bars when we're in the car. It does seem to VPN back to Canada or something FWIW, since streaming content is distinctly Canadian unless hooked up to WiFi (I did WiFi sharing from my phone for a bit just to test this, actually... and get some American content while eating/charging).
I unfortunately didn't end up turning this off, but I'll do that for the next couple weeks and see if that helps anything (assuming it gets colder again, which I don't really want it to )
Even if it is circulating a bit, I'd assume runtime is fairly low overall and I wouldn't think the fans are more than a few dozens of watts when simply recirculating air.
25km is roughly 5%, so 10% for a 24h period. Well, that actually sorta lines up with my experience. If that's the case, no one should buy an EV in areas that experience sub-zero if they don't have a warmer garage. That is a lot of wasted energy, and a lot of wasted money (esp. for someone who doesn't drive much). Our monthly usage is about $40-50 with a 120km commute every day, so we drive a lot. At $1/day for standby losses, that would almost double our bill even with a longer commute. Ridiculous. Thankfully it's in a garage at home that doesn't usually get below 10C.
You lost that much even in the garage? Ouch.
Sentry is only on when we toggle the icon on the top of the display, no matter where we are. It is currently off, verified to be off, and has been off for a few months (once I realised how much power it takes). The one time I'd like to use it (e.g. hotels, like now!) I just can't make the energy sacrifice.
I like this theory. I can get my wife's voltmeter out once she's done work for the day, but I doubt that's going to tell us much.
Haha, I'm remembering how mad I get when updates change settings (be it Microsoft or Tesla, both do this). I can bittersweetly report that settings have been double-checked and everything I want off, is off.
I do have storage plugged in for DashCam, but Sentry is off and like I mentioned, this hasn't previously hurt my usually great vampire losses.
Some interesting new data/anecdotes. I realise this is all fairly imprecise for now.
- It has warmed up. The excessive drains I was seeing before are now completely gone, and temperature is the only thing that has changed. Cold is definitely the primary factor.
- I apologise for a lack of number records, but I can mostly assure that the losses I've seen are not to do with the readings being lower simply due to being cold (i.e. I never took a hot battery reading vs. a cold battery reading, though "cold" may have varied by maybe 3 degrees C)
- Last night I forgot something in the car and went to it an hour after we parked it to discover that climate control was running (confirmed via app before I got to the car). All doors were closed, car was locked, and the climate control in the car was not set to on/dog/camp when I got inside it. It wasn't that warm in the car (but definitely warmed), so I'm not sure if it had just turned on a few minutes prior or if opening the app triggered it (it shouldn't, right?). I'm not ruling out that I hit the climate button by accident, but I of course will doubt it. I got my stuff, closed the door, locked the car (confirmed), went back inside and checked the app again and the climate control was still on. Finally turned it off from the app. If it had been doing this on the colder nights, it would certainly be draining a lot!
Maybe given the above, the state of the BMS has been completely whack (or perhaps it's indicating some non-ideal scenario inside the pack). I know one thing I'm struggling with is that the trip estimator is egregiously optimistic -- for longer trip durations, it normally expects that I do 20% "more efficient" even when I stay below the speed limit and have climate control completely off. Using climate predictably makes it worse. We're fairly close to ABRP estimates though, within 1% mostly. Not sure if the Tesla trip planner is normally this bad, folks on this forum usually say it's pretty accurate (and it is for us in summer). Might be entirely unrelated.
Android, unfortunately. As for cell service, I'm not really sure what's up. It's full bars when we're in the car. It does seem to VPN back to Canada or something FWIW, since streaming content is distinctly Canadian unless hooked up to WiFi (I did WiFi sharing from my phone for a bit just to test this, actually... and get some American content while eating/charging).
I unfortunately didn't end up turning this off, but I'll do that for the next couple weeks and see if that helps anything (assuming it gets colder again, which I don't really want it to
)Even if it is circulating a bit, I'd assume runtime is fairly low overall and I wouldn't think the fans are more than a few dozens of watts when simply recirculating air.
25km is roughly 5%, so 10% for a 24h period. Well, that actually sorta lines up with my experience. If that's the case, no one should buy an EV in areas that experience sub-zero if they don't have a warmer garage. That is a lot of wasted energy, and a lot of wasted money (esp. for someone who doesn't drive much). Our monthly usage is about $40-50 with a 120km commute every day, so we drive a lot. At $1/day for standby losses, that would almost double our bill even with a longer commute. Ridiculous. Thankfully it's in a garage at home that doesn't usually get below 10C.
You lost that much even in the garage? Ouch.
Sentry is only on when we toggle the icon on the top of the display, no matter where we are. It is currently off, verified to be off, and has been off for a few months (once I realised how much power it takes). The one time I'd like to use it (e.g. hotels, like now!) I just can't make the energy sacrifice.
I like this theory. I can get my wife's voltmeter out once she's done work for the day, but I doubt that's going to tell us much.
Haha, I'm remembering how mad I get when updates change settings (be it Microsoft or Tesla, both do this). I can bittersweetly report that settings have been double-checked and everything I want off, is off.
I do have storage plugged in for DashCam, but Sentry is off and like I mentioned, this hasn't previously hurt my usually great vampire losses.
While you're right that I could have provided more info in the initial post (please excuse my panic given the situation and lack of charging options), I think the rest of the thread makes it clear that I have somewhat of an idea of energy management with the car already, thanks to people providing great feedback despite the numerous times the topic comes up. In fact, every time it comes up fresh, we seem to get more of an idea how things work. I've observed @AlanSubie4Life 's knowledge and helpfulness for example has greatly increased in the past few months. I applaud folks like him for trying to genuinely help out in each case despite how repetitive it might be. Turns out, we all have a lot to learn. And if nothing else, the darn car's behaviour seems to change every few months as well. Last winter season's knowledge can be misleading compared to today's updates!
And I can't imagine some average A-to-B commuter driving this car, yikes. No wonder people stick to gas if you need to know all this stuff and continue learning as information develops.
I think it boils down to that large drops in battery power must either be caused by the HVAC system or the powertrain.
AlanSubie4Life
Efficiency Obsessed Member
I’ve considered this before, but in order for this to happen, the 12V would have to be exceedingly bad, I think (work the numbers...), and they have detection of that sort of failure, I thought...the 12V battery often warns people prior to needing replacement. I would imagine a pretty narrow range of leakage is allowed.
@camalaio, no idea what is up with your experience. Seems strange. Certainly if the car is not sleeping reliably this would be the result. Why that would be happening in the cold, I am not sure.
It sure would!
And if you went back to your car and opened the door, the climate might turn on and dump 5-10% of energy into HVAC to warm the cabin. Actually, that is what happened.
In this case, it was not on while you were not there, rather it turns on when you open the door. You need to turn off HVAC before leaving the car or upon entering in this case. It turns off when you leave, but not after draining 10% battery (in extreme climate), and possibly even more if the doors were open for an extended time w/ climate on.
New technology has its pros and cons. Back in the 60s it was common for people to work on their cars, change oil, brakes, etc. You are just expecting that your ICE knowledge and expertise will transfer over. The problem is worse the older you are.
People experienced with ICE cars still leave the lights on and they wake up in the morning complaining about "vampire drain". If they don't know how to charge a battery, they certainly have friends/relatives who helped them and educated them.
You are an "early adopter" so your friends+family will be of no help. In 10 years they will be asking you these questions.
I'm trying not to dismiss the possibility that this is the case, but it leaves open some questions. Are you saying it runs the HVAC for well over an hour after leaving the car and locking it up? The heater maxes out at 6kW I believe, and 2kW for the A/C. Assuming both ran continuously at max (they wouldn't), it would take nearly an hour to drain 10% of an LR battery. This doesn't seem right.
I can't remember if the nights align or not, but there were also days where we started and ended our drive with climate control off. If it's turning on after we leave and lock the car, I cannot fathom any beneficial reason for that behaviour. I'd happily burn over to California and give someone at Tesla HQ an earful for that.
I'm not even 30 yet haha, but I have indeed worked on my own vehicles with my dad, who is a mechanic. If it were a matter of maintenance being different that'd be fine for most people. I'm referring to literally having the car parked being a burden here. Even looking at it myself as an excited early adopter, this is not the way forward if this is how EVs behave in the cold. In my province (which is a bit cold), we're trying to ban sales of gas/diesel vehicles by 2040. I have concerns if every vehicle here starts burning through 6kWh every day just to be parked.
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