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NigelM
Recovering Member
I find a loss of about 3 km (1,8 miles) pr day to be completely acceptable. My main concern with the major vampire-loss was leaving the car at airports for a couple of weeks for instance, but this seems more than doable now
Nobody should forget that it will hopefully become more than doable after we get the FW update. My recent experience is losing 8-10miles per day in a warm weather climate; if I'd left my car at the airport for two weeks I would have been close to zero by the time I returned. (I left it at the Tesla service center instead so no problem, but not everyone has that option)
So I used the Tesla API to read the battery level every 30 minutes so I could plot battery drain overnight. Every night I check I see slightly different results. But as you can see in this graph the car will go for 2 hours without any loss and then a steady decline for about the same time.
I believe the big drop is the battery cooler kicking in. Some nights I see this and some I do not. I think the slow discharge could be charging the 12 V battery which is being discharged by various items mentioned above. I work in the garage and sometimes I heard the big contactor kick on and then you can hear the sound of a pump. The car is alive. Some nights before going to bed I see that the display over the steering wheel is on for no reason. That would take power...
I believe the big drop is the battery cooler kicking in. Some nights I see this and some I do not. I think the slow discharge could be charging the 12 V battery which is being discharged by various items mentioned above. I work in the garage and sometimes I heard the big contactor kick on and then you can hear the sound of a pump. The car is alive. Some nights before going to bed I see that the display over the steering wheel is on for no reason. That would take power...
Very nice plot. Regarding battery cooling while the car is off, see post 533 where ddruz shares an email from Tesla rep Walter Frank:
The loss of range when the car is off has absolutely nothing to do with energy needed to heat, cool or otherwise do anything to the battery pack. The battery pack simply doesn't consume energy when the car is off nor do the systems that manage it. All of the "sleep" energy loss is going to onboard computer systems and providing the useful benefit of keeping them ready to start-up at a moment’s notice when the driver returns. As noted above this energy consumption will be almost completely eliminated over the next 2-6 months.
It could easily use no power IF it were not active when the car is not plugged in.
However, with reports of the pumps turning on and off while the car is parked and unplugged, that is questionable.
Much of the loss over the winter was due to the algorithm used to predict range and not a true loss of power. Note, I didn't say "all" of it, but a lot of it was.
Do we have recent data from folks in hot weather country parking unplugged for a number of hours? That may give us better data.
I take him to mean that the car does not try to regulate the temperature of the battery when the car is off.
I think that there must be at least one exception to Walter's statement. When the temperature is below freezing and the car is preparing to charge, the battery pack needs to be heated. This may account for some of the difference between warm and cold weather vampire losses, but I'm not totally sure.
All that said, if we take Tesla's claim at face value - that they are going to eliminate vampire losses - the only way that is possible is if either battery management takes almost no power (seems very unlikely) or the car doesn't manage the battery when off (aside from when charging).
I find a loss of about 3 km (1,8 miles) pr day to be completely acceptable. My main concern with the major vampire-loss was leaving the car at airports for a couple of weeks for instance, but this seems more than doable now
This would be a loss of about .5 kW. I would be ecstatic!!!!!!
NigelM
Recovering Member
Yes, just up-thread:
During TESLIVE I left my car at the airport under covered parking with daytime temps 85-95F, lost 35 miles in 4 days. After that I was planning a two week vacation so tested (on several occasions) leaving the car unplugged 24hrs and consistently had losses never less than 8 miles and not more than 10. I talked to a local service manager and, even before I told him my experience, he said expect up to 10 miles per day loss.
so if the Tesla rep is indeed correct and there is power to the BMS when off, how do we explain the sudden drop between 12:30 and 1 am? I too have heard clicks and pump noises which seem to be coming from the battery pack.
EarlyAdopter
Active Member
Under v4.1 when sleep was previously enabled I would loose about 3 miles (1kWh) per 24 hours. 4.1 sleep turned everything off, including the center 17" screen and couldn't be woken up for the phone app. 5.0 sleep leaves a few things on, so I'd expect losses to be closer or slightly more than 4.1. Unless of course the wizards at Tesla have worked their magic.
It's a confusing post to me. I think he's saying that he lost 80 miles in 14 days of his car being unplugged which is 5.7 miles lost per day. That's not crazy but I would hope for less loss than that on a daily basis.
Ok, this morning 231 miles indicated from overnight charge @20A. So new software upgrade now pegs a full standard charge at 230 miles instead of the old 240. So with 160 miles remaining after 14 days being idle and unplugged, the vampire loss actually equals 70 miles. Thus I'm genuinely, unambiguously pleased!! Frankly, I expected more losses.
Normally this car is plugged in at all times. This time I thought it would be interesting to observe vampire losses in car I just trailered back from Service. So ZERO miles driven since their full standard charge, their fresh 4.5(1.33.61) upgrade, and a brand new traction battery installed in the car. Over the 14 day period I moved the car around the yard a few times and observed 'CAR OFF' on the speedo screen. Made no special effort to TURN CAR OFF since I did not wish to mess with the new firmware.
So, for example, two full weeks at Airport Parking and you have enough left over to drive ~80 miles home. Not bad at all.
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Normally this car is plugged in at all times. This time I thought it would be interesting to observe vampire losses in car I just trailered back from Service. So ZERO miles driven since their full standard charge, their fresh 4.5(1.33.61) upgrade, and a brand new traction battery installed in the car. Over the 14 day period I moved the car around the yard a few times and observed 'CAR OFF' on the speedo screen. Made no special effort to TURN CAR OFF since I did not wish to mess with the new firmware.
So, for example, two full weeks at Airport Parking and you have enough left over to drive ~80 miles home. Not bad at all.
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