Power drain while idle (Vampire Load)

[Cottonwood]

I suppose the health of your 12V affects the vampire draw. Are the both near the same age? I only seem to get about 2 years out of one before it starts to lose enough capacity that it attracts Tesla's attention.

Do you have any idea how much extra drain is the result of always connected?

The P85D was delivered new in 12/14 and the P85 Sig had its 12 V battery replaced in April. Both 12 V Batteries are relatively new.

 

[Lex]

I have been watching the vampire drain my battery for several days while I am away from home.

View attachment 39702

Definite pattern of ~9 hours of sleep followed by ~3 hours awake on a very regular basis over the past several days. I still need to find out what the car thinks its doing during the extended waking periods. My guess is it is trickle charging the 12V battery but I'm not sure how to prove that.

K so I read this thread backwards (latest first) and it was late at night (teslomnia I think is what it's called lol) but could have sworn there were no PhD theses published on this post

And it seemed the 12V batt charging possibility just needed a new test bobble dodad thingie, but did I miss the answer ???

The "vampire drain" is probably just a fact of life for us, and perhaps an admittance of this may actually help with future firmware and apps, eg. battery warming at the right times if you are honest about how long you're leaving your baby in the cold :wink:

or is Sir Elon conducting protein folding on our mobile compute platforms and crediting his team ??? lol

 

[AustinPowers]

I just leave it plugged in when I'm gone.

Meaning what? That you don't have charging losses or vampire drain? I don't think so.

I come back to this thread because a colleague asked me specifically about charging efficiency and vampire losses on the Model S and I could not give him a specific answer on either topic.

This thread caught my attention, because the OP seemed to indicate that losses in the range of 3 kWh per day without driving were normal. What is the current status? Because 3 kWh per day to me seems extreme.

When I calculate that at our electricity rates it would mean over 300 Euro per year even if the car wasn't moved a foot. And considering that I pay only about twice that amount for my average yearly Diesel consumption for around 8k kilometres, 300 Euros for nothing doesn't really correspond with a BEV supposedly having favorable running costs compared to an ICE.

Especially factoring in that the electricity I would have to use for 8k kilometres (taking the 70D as an example, with 442 km (according to the admittedly optimistic NEFZ cycle) per full charge) would come to another 380 Euros per year (8k km divided by 442 km, multiplied with 0.30 Euros per kWh multiplied with 70 kWh). And that calculation only works at 100% charging efficiency, which doesn't seem realistic either. So realistically, the cost would be even higher.

Or am I getting this all wrong?

 

[Matias]

IIRC idle power consumption (i.e. vampire load) is around 50W. So 1.2 kWh in 24h.

 

[Only Trons]

I normally plug in my MS every night in my enclosed garage. Charging set to 90% (225 RM for my car). In the morning, I will typically find the RM to be somewhere between 221 and 225. I know the MS will periodically enable charging to keep the battery charged to the requested level, so 221 - 225 didn't concern me. Lately I've come to the car in the morning and found RM to be 218 or 219. Hmmmm. So I decided to keep the car unplugged and measure the amount of vampire loss. I was surprised at the amount of my vampire loss --- it seems to be more than I recall from earlier observations.....now at 8 - 10 RM per day????

Details of my car and conditions:

• VIN XXXX08404
• Delivered April 2013
• Software version 6.2 (2.5.36)
• Energy saving ON
• Always connected NOT selected (e.g. off)
• Remote Access ON at first and then OFF (details below)
• Daily temperatures in garage between low 60's and upper 70's
• Key fobs both in RFI bags and stored greater than 50 feet away with garage wall and one interior wall separation
• Not using smart preconditioning
• Original 12V battery
• Not currently using Visible Tesla

First day was measured over 14 hours -- the car sat unplugged from 4 pm in the afternoon to 6 am the next morning. Loss of 5 RM overnight. This would equate to a loss of 8.5 RM in a 24 hour period (using a linear extrapolation).

Second day --- checked the car at 6 am the following morning. Loss of 8 RM overnight. TURNED OFF REMOTE ACCESS AT THIS POINT.

Third day --- checked the car at 6 am the following morning. Loss of only 4 RM overnight. Hmmmm...didn't expect this because I had not been remotely checking the car. However.....

Fourth day --- checked the car at 6 am the following morning. Lost 10 RM overnight !!!!!

As noted above, I have not used the mobile app during this time to connect to the car. I only access the car one time per day --- at the time I open the door and read the RM display on the IC. At the last reading, I did plug in a 12V battery charge tester into the 12V power socket ... it read 14.2V.....same as it usually does.

So a total of 27 RM loss over essentially 3.5 days --- average loss of 7.7 RM per day. I can't figure out why the loss was low on just the one day but similar on the other days.

I've read many of the other threads here on TMC about vampire loss. I know that vampire losses were supposed to be reduced with newer software builds and, of course, owner choices such as use of Remote Access or Always Connected. But my vampire losses now seem to be as high as they were in the earlier days.

 

[apacheguy]

Sounds like the 12 V might be going bad

 

[AmpedRealtor]

I'm almost certain it's your 12v battery nearing the end of its life. I also experienced higher vampire drain just before I received a service alert to replace the 12v battery. Often, when checking on the car using my app, I noticed the car wasn't sleeping. This is an indication that the 12v is waking up the car for a recharge more often than it should. My August 2013 Model S has already had its 12v battery replaced due to normal cycling. You're car is older, yet you are on your original 12v. That's where I would place my bets.

 

[SmartElectric]

considering that I pay only about twice that amount for my average yearly Diesel consumption for around 8k kilometres, 300 Euros for nothing doesn't really correspond with a BEV supposedly having favorable running costs compared to an ICE

I look at this from a different perspective:

Considering that the average diesel car pollutes significantly more than an EV, 300 Euros doesn't really correspond to any serious running costs compared to the environmental degradation caused by gas/diesel mining, pipelines, refining, transportation and eventual decommissioning of sites where these products were mined and consumed

Just because you don't pay directly for all the other costs of gas/diesel consumption doesn't mean those costs aren't born by others or the planet.

We're driving two EV's now, and never going back to gas.

 

[rypalmer]

Adding a data point for the curious. I was away and just got back, and my car ended up sitting around doing very little for 17 days and 1 hour. I do not have charging at home and knew that with vampire load I would be cutting it close.

• VIN 125xxx
• Delivered June 2016
• Software version 2017.32.6 ca28227
• Energy saving OFF (forgot to change this)
• Always connected YES
• Remote Access ON
• Daily temperatures probably didn't fluctuate much between 5-15ºC
• Not using smart preconditioning
• 12V battery replaced once
• Using TeslaFi, but LTE/3G and WiFi service unavailable in the underground parking garage

State of charge Oct 29: 22% / 87km
State of charge November 15 (+17 days 1 hour): 6% / 22km

I limped uphill to the Toronto Supercharger and arrived with 1%