Under review

Display vampire drain rate for my vehicle

mkolowich 2 years ago • updated by steev 2 months ago 13

Helping car owners to understand/estimate vampire drain would be a major help. This could be done in several ways:

  • with data display (I.e. when idle, display current vampire drain rate [lost range, in miles/day] in top status bar)
  • with graph (i.e. show bar graph of vampire drain rate [lost miles / day] for different connection states (connected, sleep, deep sleep))

Even more importantly, I think it would be a great service to run a regression, across the entire database, to discover exactly what influence each of the following has (if any) on vampire drain rate [lost miles / day]:

  • connection state (connected, sleep, deep sleep)
  • state of charge (current % charge level)
  • outside temperature
  • battery size (kWh max capacity)
  • car model (S, X, SP, XP, 3)
  • time since last charge

The results would help car owners understand exactly how to minimize vampire drain on their car, and to understand, for example, how much vampire drain to expect when, say, parking their car at the airport during a three-week vacation


One source that I noted after cursing at my car for not going to sleep today as it heated up.. Cabin overheat protection. It seems that having this on wakes the car up when it hits 105F and it'll refuse to sleep during this period. I thought my wife was poking at my car all day keeping it awake. Then I realized I had this on, ran out and turned it off and the car fell right asleep. Just something to keep in mind if you turned that feature on.

I'd also like the ability to tie vampire drain to specific builds. I'm envisioning some sort of pivot table functionality.

Even the settings around sleep are someone convoluted... so much trial and error to see what works.  Simplifying that in any way would be appreciated.

I would like to see the average power during the sleep.  KW-hr used during the sleep period / the sleep period in hours

If this feature is implemented I'd like to be able to set a range of time to analyze - the behavior of my car over the past few weeks or months (or on the current firmware version) will be a better indication of what I can expect than the lifetime behavior.

I think it would be great to graph idle time range loss (as shown each day in the right column) vs. temperature, similar to the drive efficiency vs temperature graph. I noticed that I have 20-30 miles of range loss each day but right now I can only see that clicking on each individual day. It would also be nice to see this number listed for each day on the calendar.

would be helpful to measure battery heating power

I'd like to see a graph showing actual miles driven vs. rated miles.  This would help drivers determine actual battery mileage needed during colder months.

I work in residential energy efficiency and would guess most Tesla owners would be astounded to find out how much energy these things consume when sitting idle in the garage if you have the "wrong" options enabled. I've only had the car for six weeks, but recorded standby losses over 400 watts (I installed a revenue grade meter inline with the charger to monitor total charge rates) before I figured out better settings. That's crazy bad -- like having an extra jacuzzi in the back yard. 

Most owners will just look at their dashboard and say "295 watt hours/mile... great!" but will have no idea the real number may be over 400 when these standby losses are taken into account. 

Your TeslaFi service is wonderful! Please provide more insight into this area of wasted energy, if possible.

Not true. When on standby the charger pulls 2 watts. There is a physical relay in the charger. The car is only connected when it is actively charging or running the HVAC, and your charger will animate the lights showing that. Power draw will then be in the kilowatts. I monitor power both via TeslaFi and a circuit meter inside the house.

Thanks for clarifying. I didn't mean to indicate the charger had a high vampire load -- it's the car. I leave the car in the garage for days at a time undriven, and can see from the meter I installed how much charging is required just to maintain the range. 

You wrote earlier "I have 20-30 miles of range loss each day"... at 300 Wh/mile, I think 24 miles lost in 24 hours would equal "vampire loss" of 300 watts.

Need. It seems a mystery for the battery drain for telsa