I see that definition further down in the Wikipedia article. I was reading the earlier paragraph that said battery.
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AlanSubie4Life
Efficiency Obsessed Member
This thread fills me with melancholy. It's mostly about comparing Bolt efficiency & Model 3 efficiency, and basically both are really good in driving efficiency, with different strengths and weaknesses (and it may be that the Model 3 would be better all around efficiency (while driving) with equivalent tires). But, since vampire drain doesn't exist for GM products and it does for Tesla...and all threads end in vampire drain discussion...
I certainly do not know exactly what is causing the vampire drain, but the OP's post clearly shows the impact. I want Tesla to succeed, and I love the way my car drives, and in general I love it. However, I don't drive tons of miles in it, as I like to bike to work and minimize my energy use. I have some hope that I might help save the world too, though I recognize that you don't buy a new car if you want to do that - you start taking public transport or walking... or something. In any case, I see this vampire drain adding up. This weekend, I drove a lot, but because I left my trunk lid open (I know, my fault!), I also drove 20 miles in my garage (normally it would be closer to 12 over 3 days). That's on top of the actual 120 miles I drove. This seems like a poor ratio.
I'm also an electrical engineer, with some decent experience with low power wireless systems, and unless this truly is some sort of crazy mandatory battery management that is taking place (which Tesla does NOT say it is - they imply it is for the "electronics"), I can assure you that in this day and age, it really is completely unnecessary to burn anywhere near the 30-40W that Tesla says you should expect, for any of the functions that people want. For a properly engineered system, where standby power is a critical design consideration, it is not needed. I also recognize that standby power accounts for ~1% of worldwide CO2 emissions (while air travel accounts for ~3%). It is significant! We should want it minimized, if possible.
So, for the cake that people want (connectivity, wakeup, OTA updates, etc.), it is possible to have that cake, and eat it too. It's not a choice you should have to make between these features and vampire drain. Delicious cake.
I also saw a comment above about vampire drain being good because of the reduced battery issues, but I believe that we KNOW at least three things, related to vampire drain:
1) Cycling the 12V battery will lead to premature failure (there is so far no evidence that they constantly trickle charge it bypassing the contactors), relative to not cycling it. So, this vampire drain is cycling the 12V battery. This will not have positive consequences for owners.
2) The contactors will fail if they have excessive cycles. Every unneeded sleep-idle transition is a contactor wear cycle. For whatever reason, I noticed this weekend a lot more of the contactor cycles when I was around my car - I don't know why. When contactors wear out, the HV battery needs to be dropped out of the car AFAIK. To replenish the 12V battery, the contactors have to be closed (AFAIK, see above). Vampire drain is hurting the contactors.
3) We know that using lithium ion batteries degrades them (though shallow cycles are pretty benign). Vampire drain puts miles on the battery. This is likely a very small, negligible impact of course (probably much smaller than the aging of the battery). But I don't think we can say it doesn't exist.
So, I don't know that we have any evidence that vampire drain actually helps anything. Anything positive, with some evidence?
The time is coming (I would guess 1-2 years at the earliest) when Teslas will be seriously compared against other offerings in the same target market. As a stockholder, and also as a car owner, I want Tesla to succeed. I don't think vampire drain will make or break things, but in the SR offering, people are really going to notice! And I guarantee competitors will bring it to light (and get it added to the EPA test even) when things start getting serious. It's a problem I would prefer that Tesla not have to panic about when it comes to light. Why not just fix it sooner rather than later?
I'm sure I could come up with all sorts of tests to measure exactly where the drain is going, and ways to "prove" that it's not battery balancing...but I kind of feel like that isn't my job - and also Tesla says that isn't what they're doing. (Owner's manual, page 122).
If they act soon, they'll be ahead of the curve on the EPA standards, we'll be able to talk about other more interesting things on the forums, competition will continue to get clobbered, etc. It's important that Tesla be able to do the simple things well, in addition to the really complicated things. It's a complex, well engineered vehicle overall, just got to patch up a few things...
I certainly do not know exactly what is causing the vampire drain, but the OP's post clearly shows the impact. I want Tesla to succeed, and I love the way my car drives, and in general I love it. However, I don't drive tons of miles in it, as I like to bike to work and minimize my energy use. I have some hope that I might help save the world too, though I recognize that you don't buy a new car if you want to do that - you start taking public transport or walking... or something. In any case, I see this vampire drain adding up. This weekend, I drove a lot, but because I left my trunk lid open (I know, my fault!), I also drove 20 miles in my garage (normally it would be closer to 12 over 3 days). That's on top of the actual 120 miles I drove. This seems like a poor ratio.
I'm also an electrical engineer, with some decent experience with low power wireless systems, and unless this truly is some sort of crazy mandatory battery management that is taking place (which Tesla does NOT say it is - they imply it is for the "electronics"), I can assure you that in this day and age, it really is completely unnecessary to burn anywhere near the 30-40W that Tesla says you should expect, for any of the functions that people want. For a properly engineered system, where standby power is a critical design consideration, it is not needed. I also recognize that standby power accounts for ~1% of worldwide CO2 emissions (while air travel accounts for ~3%). It is significant! We should want it minimized, if possible.
So, for the cake that people want (connectivity, wakeup, OTA updates, etc.), it is possible to have that cake, and eat it too. It's not a choice you should have to make between these features and vampire drain. Delicious cake.
I also saw a comment above about vampire drain being good because of the reduced battery issues, but I believe that we KNOW at least three things, related to vampire drain:
1) Cycling the 12V battery will lead to premature failure (there is so far no evidence that they constantly trickle charge it bypassing the contactors), relative to not cycling it. So, this vampire drain is cycling the 12V battery. This will not have positive consequences for owners.
2) The contactors will fail if they have excessive cycles. Every unneeded sleep-idle transition is a contactor wear cycle. For whatever reason, I noticed this weekend a lot more of the contactor cycles when I was around my car - I don't know why. When contactors wear out, the HV battery needs to be dropped out of the car AFAIK. To replenish the 12V battery, the contactors have to be closed (AFAIK, see above). Vampire drain is hurting the contactors.
3) We know that using lithium ion batteries degrades them (though shallow cycles are pretty benign). Vampire drain puts miles on the battery. This is likely a very small, negligible impact of course (probably much smaller than the aging of the battery). But I don't think we can say it doesn't exist.
So, I don't know that we have any evidence that vampire drain actually helps anything. Anything positive, with some evidence?
The time is coming (I would guess 1-2 years at the earliest) when Teslas will be seriously compared against other offerings in the same target market. As a stockholder, and also as a car owner, I want Tesla to succeed. I don't think vampire drain will make or break things, but in the SR offering, people are really going to notice! And I guarantee competitors will bring it to light (and get it added to the EPA test even) when things start getting serious. It's a problem I would prefer that Tesla not have to panic about when it comes to light. Why not just fix it sooner rather than later?
I'm sure I could come up with all sorts of tests to measure exactly where the drain is going, and ways to "prove" that it's not battery balancing...but I kind of feel like that isn't my job - and also Tesla says that isn't what they're doing. (Owner's manual, page 122).
If they act soon, they'll be ahead of the curve on the EPA standards, we'll be able to talk about other more interesting things on the forums, competition will continue to get clobbered, etc. It's important that Tesla be able to do the simple things well, in addition to the really complicated things. It's a complex, well engineered vehicle overall, just got to patch up a few things...
SageBrush
REJECT Fascism
I'd like to think that Tesla can improve in this area, but until you can show me a competing EV that has these features at a Tesla level AND less vampire drain I'll withhold any criticism.
Kant.Ing
Member
The sucker is the nvidia platform. To me it's a prototype researchers use and never should go into a product.
ℬête Noire
Active Member
??? Unless you're taking SOC well into the 90's, who is suggesting there's battery balancing going on? That's the current best-guess assumptions AFAIK, that balancing isn't triggered and happening until 93% SOC. 93% is assumed to be the specific point because of historical reasons, at least for the Model S, but the Model 3 appears to be holding the pattern at least to being in the 90's somewhere.
You didn't know that you're driving a prototype? It is true! That's how you get to drive the future today. Thus bringing us to.....
Some day there will be a BEV from another company that you can make a meaningful comparison to today's Model 3. The Bolt ain't that. Particular feature list aside, it's just a quite different car. But if you somehow expect Tesla to be standing still on this you haven't been paying attention, it's already improved over the arch of 2018.
Some hypothetical. We can very safely say it is dwarfed by heat damage. The type that drives so much of vampire drain.
Uuuuuuuuuh.
Thing is I saw roughly 10W when I actually left the car alone, even though I pinged it maybe once/day remotely (plus once I unlocked the car for someone to get something out of it). A little less than that when you factor out loss of SOC (as measured by V) due to the battery getting colder.
M3 MR vs Chevy Bolt (energy consumption)
There's work that could be done on this, but a locked vehicle being able to be ready for seamless "walk up, open, sit, and drive" is a hellva tough trick to pull off without keeping a fair amount of stuff "live". Clear priority is "working system". Energy use reduction of the order we're talking about is a very logical lower priority action item.
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SageBrush
REJECT Fascism
Exactly.
My choice then is to be given a choice. I would happily trade off a 5 second delay to cut vampire drain drastically, although I recognize that many (perhaps the majority) would not.
ℬête Noire
Active Member
I expect that'd look like a 'card key unlock only' feature? You'd still be able to unlock by digging out your phone and using the app to explicitly unlock the vehicle, of course.
Funny thing, the car is actually ready to drive before it appears to be if you judge by the main screen. The sub-system running the display is separate from parts running the drive train and handling driving control inputs (steering wheel, pedals). You can drive while that system is rebooting, even though it feels pretty weird since you don't have gear indicator, speedo, map, etc.
So the time probably isn't 5 seconds unless you don't want to move without the display or you dug the phone out to unlock that way, or you had a tough time fishing out your card.
EDIT: It'd be an interesting experiment to try out. Kill all the BT on your phones. Leave the Model 3 unplugged and sitting for a few days, on Wifi connection, and then walk up and open it with the valet key and see what happens when you try drive it.
SageBrush
REJECT Fascism
I tend to agree based on my experience with a Toyota PHEV and our LEAF. Both are ready to go in ... oh ... two seconds. Neither though have anything approaching Tesla interactivity.
ℬête Noire
Active Member
I've never put a stop watch on the Bolt's boot cycle but now after driving the Model 3 the 2 hour (?) movie I'm treated to running on the screen after I press the On button feels sub-optimal. LOL
diamond.g
Active Member
Does the Bolt make you wait for the screens to come on before letting you put the car in gear? I know the Volt does.
I don't know why the Model 3 doesn't have the always connected feature that the older S/X do (for those that say screw the drain). I know Intel supports S0 Low Power Idle on the chipset/CPU that Tesla uses. Maybe their Linux build doesn't support it?
ℬête Noire
Active Member
Yes. When we first got the Bolt it struck me as kinda goofy but whatever. This side of regular driving of a Tesla it is as eye rolling as watching 80's "near-future" sci-fi.
EDIT: Note. The Model 3 usually isn't happy about trying to put it in D immediately upon sitting. At least for me. However if you do the "proper" sequence of buckling your seatbelt first it's right there waiting for you.
There's a lot of different sub-systems rolling in a "running" Model 3. Hard to say exactly what's drawing the current. The sub-10W I saw for a "deep sleep" Model 3 isn't entirely unreasonable, although you could probably get past that if you were willing to drop remote response time even lower and really tweaked it out.
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Daniel in SD
(supervised)
Is there any feature of a Model 3 while it’s parked that’s not available in other cars?
If I have two ICE cars with 25 MPG city rating, and I drive the same route, I expect both of them to consume about the same amount of gasoline. That's what 25 MPG is supposed to measure. Losses due to hearing and AC and opening of trunks are negligible.
In case of Model 3 vs Bolt, despite having identical city MPGe, Tesla is performing around 20% worse in the city. That's a significant difference.
Once we have more electric cars, these type of energy losses will need to be disclosed and manufacturers will need to work to minimize them.
StealthP3D
Well-Known Member
seattlite2004
Active Member
Yes...per the manual below:
Although the Bolt does provide health status when I use the app while idle and unplugged... But unsure whether the checks were done in real time or maybe cached from last power on.
StealthP3D
Well-Known Member
I see you making that claim, I don't see anything to substantiate it. I'm amazed at the city MPG my LR Model 3 gets, especially in temperatures from 55F to 95F. Simply incredible the way it will beat it's rated range by a huge margin! In the winter, when I'm running the heater hard it goes down. But all my previous ICE cars got significantly worse MPG in the winter as well so I don't see why it's surprising to some people.
Bolt has remote connectivity, and claims to have the ability to do OTA. And it has zero vampire drain.
diamond.g
Active Member
Maybe folks should petition the EPA to include a "cold weather" cycle in their tests (though for ICE they would have to use Winter Blend fuel to make the comparison fair).
I measured the energy use. That's enough for me to substantiate it.
Mine M3 has never exceeded the rated range in the city. This morning, I started with 229 range, and now it is 202. I only drove 18 miles. Temperature outside was 55-60. Maybe there is something wrong and I need to take it to service.
diamond.g
Active Member
GM has had quite a few years to get the connectivity of OnStar just right for the amount of energy used. If I am not mistaken OnStar is SMS based still which allows them to really power stuff down. Have we been able to determine how the paging mechanism works for Tesla?
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