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Power drain while idle (Vampire Load)

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At mile 537 (and kwh reading of 193 on the car) on 4/4/13 I started keeping track of total energy using a wall meter.
The current reading is 2457 kwh.

Over the last 5071-537 = 4534 miles, the car reports 1696 - 193 = 1503 kwh used, and the wall meter gives
the actual usage of 2457. Or in terms of wh/mile the car reports 1000* 1503/4534 = 331 wh/mile and the wall gives
1000*2457/4534 = 541 wh/mile. If we figure charging loses of around 7.5% of the energy reported by the car,
that comes to .075 * 1503 = 113 kwh. So the total vampire drain is something like 2457 - 1503 - 113 = 841 kwh. Spread out over around 320 days, that comes to 841/320 ~= 2.6 kwh per day.

On 12/5/13 I got the 5.8 update which had the sleep function enabled. Mileage then was 4352, kwh car was 1354, kwh wall
was 1950, so repeating the above calculations for the period with sleep enabled I get, 1.075*(1696-1354) = 367 wh reported
by the car plus estimated charging losses, vs 2457 - 1950 = 507 wh. The difference is the vampire loss 507 - 367 = 140 kwh.
Spread over about 75 days, giving 140/75 = 1.9 kwh per day. This is 25% better than the total for the entire period (4/4/13->2/20/14)
but is still disappointingly high. I am scheduled to have my 12V battery replaced on Monday, so hopefully this will greatly reduce these losses
as others have noted above.
 
That's fantastic. I wonder why there is so much variability in sleep mode. I have a Sig just like you and lose significantly more than that in 24 hours. Service replaced my 12 V last month.

I'll check my data logger this evening to see what I'm actually using from the wall since I have some historical data to compare it to.
@apacheguy: Although my charge time after approx 1.75 days idle was only 10 minutes at 30 A, my vampire loss over the period was 4.73 kWh/24 hr, as measured at the wall. That's no different from a year ago (red line on graph.) I also lost 4 rated miles. I guess one reason I thought things were better is that I switched from ideal to rated miles on the display, so the miles go down less quickly for the same loss. So much for sleep mode as it currently exists. I fear this is putting a tremendous strain on the 12V.

Idle Power Loss.JPG
 
That's fantastic. I wonder why there is so much variability in sleep mode.

One reason is that there are various combinations of software versions and hardware versions. Another is that the car will wake up occasionally to top up the 12V battery. My guess is that both those account for most of the variability.
 
@apacheguy: Although my charge time after approx 1.75 days idle was only 10 minutes at 30 A, my vampire loss over the period was 4.73 kWh/24 hr, as measured at the wall. That's no different from a year ago (red line on graph.) I also lost 4 rated miles. I guess one reason I thought things were better is that I switched from ideal to rated miles on the display, so the miles go down less quickly for the same loss. So much for sleep mode as it currently exists. I fear this is putting a tremendous strain on the 12V.

Just double checking here, so 4 rated miles lost corresponded to 4.73 kWh drawn from the wall? That's over a kw per mile, I must be misunderstanding something.

Guess it's time I start measuring vampire drain from the wall instead of simply looking at the telemetry.
 
Just double checking here, so 4 rated miles lost corresponded to 4.73 kWh drawn from the wall? That's over a kw per mile, I must be misunderstanding something.
Guess it's time I start measuring vampire drain from the wall instead of simply looking at the telemetry.

Actually that was 4 rated miles lost in 1.75 days. Apples to Apples is 4.7 kWh/24 hrs and 2.3 rated miles/24 hrs. Since the time frame was so short, the standard deviation is high. There is quite a bit of scatter on the graph (see prior post), probably related to a multitude of factors which may include just how successfully the S can reach the same exact SOC on each top-off, as well the factors mentioned by Jerry.

Edit: I looked back at my data for January (I was running Version 5.8.4 / v 1.49.57 back then) and it looks like sleep mode did reduce idle power losses. I suspect that the single data point I have so far on Version 5.8.7 / v 1.49.84 may be an outlier. The following graph is slightly different in that I have plotted idle power loss vs the garage temperature 1 hour prior to beginning to charge.

[Originally I plotted the mean garage temperature between successive top-off charges because I thought that operation of the battery heater might affect idle losses. I'm not sure we are absolutely certain when protective battery heating turns on when the car is idle, but I suspect that in my garage which is heated to 33° F it probably doesn't turn on. I began to think that in my situation the battery temperature at the start of a top-off charge might be more of a factor affecting the top-off charge (ie, if the battery cooling or heating system ran during the top-off), so I'm assuming the garage temp 1 hour prior to the start of charge somewhat reflects the battery temp at the start of charge.]

Idle Power Loss v02-19-14c.JPG
 
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Just had a pretty good sleep mode experience. Parked my car at the airport at 11am on Monday with 163 rated miles of range.

Came back to the car at 11:15am (almost exactly 96 hours) on Friday and had 154 rated miles of range left.

So 9 rated miles over 4 days = 2.25 rated miles per day.

That's significantly better than my last airport parking trip, which was a loss of 6 rated miles per day. VIN P01653 and I'm now on the 1.49.84 flavor.
 
Got my original 12V battery replaced today.

But, beyond this, the service center confirmed that the "MCU indicated that the energy saver was turned off internally preventing the car from going into deep sleep"!! This is despite the UI setting being set to ON!

So, in some firmware update, the sleep setting didn't stick internally despite whatever the UI selection was.

Let me see how it goes overnight.
 
Got my original 12V battery replaced today.

But, beyond this, the service center confirmed that the "MCU indicated that the energy saver was turned off internally preventing the car from going into deep sleep"!! This is despite the UI setting being set to ON!

So, in some firmware update, the sleep setting didn't stick internally despite whatever the UI selection was.

Let me see how it goes overnight.

I had my original 12V replaced today as well, but they didn't mention anything about the energy saver being turned off internally. Since the 5.8 update, the car definitely "sleeps" in the sense that it takes a couple of seconds to start up. I've still been losing a couple of kwh a day though, much more than some people are now reporting. I'll also have to see if this changes with the new battery.
 
I had my original 12V replaced today as well, but they didn't mention anything about the energy saver being turned off internally. Since the 5.8 update, the car definitely "sleeps" in the sense that it takes a couple of seconds to start up. I've still been losing a couple of kwh a day though, much more than some people are now reporting. I'll also have to see if this changes with the new battery.

The car has been sleeping in my case as well thus far (I see the startup screen everytime) but, it apparently wasn't going into a "deeper" sleep state (much like its master most nights ;)).
 
Got my original 12V battery replaced today.

But, beyond this, the service center confirmed that the "MCU indicated that the energy saver was turned off internally preventing the car from going into deep sleep"!! This is despite the UI setting being set to ON!

So, in some firmware update, the sleep setting didn't stick internally despite whatever the UI selection was.

Let me see how it goes overnight.

Did you ever notice the car waking when you entered? Any large Tesla logo on the dashboard and delay booting up. Seems like an odd explanation.
 
So basically there would be no way for you (or any other owner) to know that you had this weird sleep condition. Damn it this puzzle just gets harder and harder to figure out.

I think I have the same problem. Sometimes my car doesn't sleep(sleep mode is always on), and I lose up to 20 miles of rated range overnight. A reboot of the center screen fixes it for a while, but I still lose about 6-8 miles overnight.
 
My guess is that the car had to heat the battery before charging. A summer vs. winter comparison (especially this winter!) makes a big difference.

Last summer, I was away for two weeks and left my car plugged in and the charge timer set for 10:00 PM. At that time, the car "topped up" to the tune of 5 kWh every other day, and the charging cycle always began exactly at 10:00 PM. This means my car was consuming 2.5 kWh / day (vampire drain).

A couple of weeks ago, I was away for 15 days and did the exact same thing. This time, my car would "top up" much more randomly. Sometimes every day, sometimes it might skip two days. While the charging always started after 10:00 PM, it was often much later than that (it did stay in my Off-Peak period, so that was good). If I add up all the consumption while I was away and divide by the number of days, it works out to 3.1 kWh / day -- MORE than before!

I have my car set to "sleep" (and it does) and I have a dedicated meter on my EV charging circuit.
 
My guess is that the car had to heat the battery before charging. A summer vs. winter comparison (especially this winter!) makes a big difference.

I wondered about that, but have never actually seen a charge cycle delayed due to pack heating while it's been in my garage. I have seen this happen when the car was outdoors and very cold. Nonetheless, I wasn't there to observe, and it was very cold, so that could be it.
 
I wondered about that, but have never actually seen a charge cycle delayed due to pack heating while it's been in my garage. I have seen this happen when the car was outdoors and very cold. Nonetheless, I wasn't there to observe, and it was very cold, so that could be it.

I saw it happen once this winter when my car sat in the garage for 24h without being driven. I told it to start charging and it took ~15mins before it started adding any range (said 0km/h charging rate). It's cold this winter!!!!!