Power drain while idle (Vampire Load)

[scottf200]

50 miles would be a full charge on a Chevy Volt, and I haven't heard of them losing that much over night.

That is true. I've not heard of the Volt losing miles at night at all actually. I have owned a 2011 for just over 2 years.

As well it is instant on when I press the start button ... or very close. The 2012+ have a "READY" prompt shot up after a few seconds but that didn't exist on the 2011. None the less it is virtually instant.

The Volt does not charge the 12v unless the traction battery is also being charged. That is it would be possible to run your 12v down even if plugged in. I know the OnStar 'connection' is lost after a few (several) days. Folks have been on vacation before and were checking on their car via the iPhone/Android app when it stopped responding. It also has a standard AGM battery. From the manual you can jump it from post under the hood or jump other cars from closer to the battery in the rear.

Just a point from a long time Volt owner with a deposit on a Model X. BTW, one of the *great* things I see about Tesla is getting software updates including some enhancements. Some bug fixes in the Volt software but no enhancements every that I've seen.

[Aside: There is a quasi FAQ thread/list on gm-volt for anyone interested: Frequently Asked Questions
And for disclosure I'm a moderator there which just means I follow/ed it pretty closely. Lot more normal (vs early adopters) on the forum now tho.]

 

[RichardC]

Long term measurement of vampire load - I measured the power consumed by our Model S over a 4 week period during which it was not driven or used (but was was remotely monitored). During this period the car automatically topped up the battery every 24 hours and consumed 149 kWhr, or slightly more than an average of 5 kWhr per day. The software is version 4.2. The car was stored indoors, in an insulated garage with an average temperature of around 40 degrees F. On an annualized basis these losses are roughly equivalent to the power that would be used to drive approximately 6,000 miles or 10,000 km and represent power actually wasted (as opposed to temporary reductions in the stated range). The available range was the same after consuming the 149 kWhr as it was before. From my perspective this is a serious issue that TMC needs to address as soon as possible.

 

[Iz]

I have the 60 kWh S. Displayed 186 miles on it's maiden voyage to work this morning. Trip is ~ 33 miles. When parking at the office it read 150 miles. 9 hours later after work I get back in and it reads 131 miles. Temps were in the 40's most of the day. Drove home and range was ~ 111 miles (will have to keep logs to be accurate). I have to charge @ 110 Volts for the time being. Did not charge immediately upon returning home. Went out just after midnight and range was 92. It is now charging. Appears to charge @ 4.5 miles/hour on 110 volts. I think these issues will be addressed over time. Love the vehicle. Can't even think of getting back into the Sienna :love:

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Sometimes when I start driving, the rated range holds for a bit - so not all those miles were "lost" but that doesn't happen that often.

Noticed some of that today while driving home from work.

 

[tezco]

Currently losing about 12-16 ideal miles /24 hrs; takes 3-5 kWh each 24 hrs from the wall to replace.

 

[ElSupreme]

Looking through all of this I am thinking I shouldn't leave my Model S at the airport for 9 days and expect it to get me all the way back.

I have about 220 miles left (I am at work). Not allowed to plug in, even to 120V as I am on a client's site. Don't have the cord anyway.
I will have about 185 miles left when I get home.

I can charge for 1.5-2 hours. And get to 245 (full standard charge, but I'll be in range charge).
I'll have 215 miles after getting to the airport. I'll burn about 30 miles going to the airport.
At 8.5 days parked, I could lose up to (15 miles a day at 9 days to be safe) 135.
I have 80 miles to get back home. Which would take about 30 miles of range.

I guess even if I lost 20 miles per day I could probably still limp home.

Your thoughts? I leave for the airport at 5pm ET. Does anyone know if the vampire load gets less as the battery loses capacity?

I would obviously bring my charge cord in the car. But won't have anything to plug into.

 

[Rodolfo Paiz]

I might try that as long as I have both a Plan B and the time/patience to implement it if necessary.

 

[gregincal]

I might try that as long as I have both a Plan B and the time/patience to implement it if necessary.

Yeah, we'd all love you to try it and report the results. Come on, take one for the team! Seriously, are there any charging stations between the airport and home that you could use in a pinch?

 

[ElSupreme]

Yeah, we'd all love you to try it and report the results. Come on, take one for the team! Seriously, are there any charging stations between the airport and home that you could use in a pinch?

The wife has basically told me she won't complain for ALL of SXSW (it is my birthday) up until we get back to our house. And knows there is a small chance of being stranded at the airport. So I will be leaving it unplugged at the airport, uncovered. I'll try to log the battery state of charge at the same time every morning for the days it is gone. So there will be some data, other than do/don't park your car outside for 9 days.

This will also alert me to getting a ride from the airport if my car is dead. And I should be able to plug it into a wall in the car lot I am going to, if it ends up being dead and leaving it parked for an additional day. So I have my plan B.

Oh and I just realized one of those days is 25 hours long. So I should be extra worried! :biggrin:

 

[Dave EV]

Wow, the vampire load of the Model S really appears to be horrendous. We have multiple people confirming 3-5 kWh / day from the wall to keep the car charged, or about 90-150 kWh / month. Those data points are in cool temperatures (above freezing, below 55F). Anyone in a warm climate (Florida?) have any data?

Let's say you drive 1000 miles / month and average 3 miles / kWh which would be around 333 kWh / month. Vampire load could be decreasing your efficiency by 25-45%! That is rather insane...

The Roadster had similar issues when it was first released. Anyone have current data on the Roadster to compare?

 

[ElSupreme]

Wow, the vampire load of the Model S really appears to be horrendous. We have multiple people confirming 3-5 kWh / day from the wall to keep the car charged, or about 90-150 kWh / month. Those data points are in cool temperatures (above freezing, below 55F). Anyone in a warm climate (Florida?) have any data?

Let's say you drive 1000 miles / month and average 3 miles / kWh which would be around 333 kWh / month. Vampire load could be decreasing your efficiency by 25-45%! That is rather insane...

The Roadster had similar issues when it was first released. Anyone have current data on the Roadster to compare?

Yeah I did the calc yesterday night how much I would lose at the airport. And it was WAY more than I realized. But remember that there is NO sleep mode right now. I would expect 1-2kWh per week when that gets pushed out.

I think of the vampire load as running another server at home. I tend to think my server pulls about 150W continuously. I'm pretty sure my stupid cable box pulls more than that at all times.

 

[Doug_G]

The Roadster had similar issues when it was first released. Anyone have current data on the Roadster to compare?

If it doesn't need cooling, the Roadster vampire drain is tiny. A couple of miles range per day at most. It takes months to drain it.

 

[RichardC]

Yeah I did the calc yesterday night how much I would lose at the airport. And it was WAY more than I realized. But remember that there is NO sleep mode right now. I would expect 1-2kWh per week when that gets pushed out.

I think of the vampire load as running another server at home. I tend to think my server pulls about 150W continuously. I'm pretty sure my stupid cable box pulls more than that at all times.

My energy losses over four weeks averaged slightly over 220 Watts for the entire period, which I have no doubt was heating the insulated garage by a few degrees C, and appears to be heating the interior of the car by around six or seven degrees C above the temperature in the garage (I monitor the outside air temperature and the temperature in the garage, in addition to the temperature inside the car).

While the current software is clearly worse than the version it replaced, I found that the losses were also quite substantial under the previous software. Even when operating version 4.1 in its lowest power consumption mode I was seeing daily losses on the order of 15 to 20 km per day, which correspond to roughly 3 kWHr per day or 90 kWHr per month. These losses were cumulative, in that the car was not being charged each day, and occurred in an insulated garage at ambient temperatures above freezing.

The difference between the vampire load of the Tesla and that of a home server is that home server is presumably performing useful functions with that power (or you could turn it off and reduce the load to zero) whereas there is no way to turn off the power wasted by the Tesla, which will continue regardless of whether the car is being used.

Incidentally, the power consumption of computers and servers is dropping such that it is possible to run a multi-terabyte home server on a little as 40 Watts (see: http://helgeklein.com/blog/2012/03/building-a-low-power-high-capacity-home-file-server/ )

 

[neroden]

Long term measurement of vampire load - I measured the power consumed by our Model S over a 4 week period during which it was not driven or used (but was was remotely monitored). During this period the car automatically topped up the battery every 24 hours and consumed 149 kWhr, or slightly more than an average of 5 kWhr per day. The software is version 4.2. The car was stored indoors, in an insulated garage with an average temperature of around 40 degrees F. On an annualized basis these losses are roughly equivalent to the power that would be used to drive approximately 6,000 miles or 10,000 km and represent power actually wasted (as opposed to temporary reductions in the stated range). The available range was the same after consuming the 149 kWhr as it was before. From my perspective this is a serious issue that TMC needs to address as soon as possible.

It certainly is. While I accepted the loss -- I knew it was coming, from this forum, and I decided I wanted the car anyway -- it means I'll literallly be wasting more power with the car than I will be using driving the car. It also means I'm spending just as much in electricity as I was spending on gasoline. And as others have noted, it means that there's no way the car can be left unplugged at a distant airport (or train station) for weeks. It's a huge bug and it needs to be fixed.

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Vampire Draw is happening because Tesla was having trouble with some systems going to sleep and then waking back up again correctly. So they stopped putting anything to sleep. No more bugs but now we have vampire drain. It's a serious problem and I know Tesla is working hard to eliminate it. It will be solved in time.

I hate to say it, but my bet is on bad drivers from nVidia, in which case they're not going to fix this quickly.

 

[JRP3]

In his recent talk in Norway I think I remember Elon saying sleep mode would be fixed before they received their cars, so that would be June or July at the latest, to give some time frame. Hopefully sooner.

 

[gg_got_a_tesla]

4.3 - presumably with sleep mode available again along with the charge timer - is in beta testing with some owners already so, it's going to be much sooner than June, IMO.

It is indeed sad to see all that energy being wasted. If the chips onboard could pitch in with Folding@home or some such distributed computing project while they are awake, that'd have been okay

 

[brianman]

I hate to say it, but my bet is on bad drivers from nVidia, in which case they're not going to fix this quickly.

I seriously read this the first time and thought "Dude, how do you know they don't know how to drive? Why did you come to that conclusion?" First time for me that context didn't make the intended meaning of "driver" obvious.

 

[shokunin]

I hate to say it, but my bet is on bad drivers from nVidia, in which case they're not going to fix this quickly.

The losses seem to be on the order of 150w/hr or more. They'd have to be using upwards of 10 Tegra 3's to hit that number. The TDP of Tegra 3's are between 5-20w depending on load. With the car off, the processors would be at idle even without sleep.

However, we don't know what silicon they are using for embedded systems. Regardless, it's a power hog and hope they get this under control.

 

[Kipernicus]

I find it interesting that the trip meter doesn't record the vampire loss. I arrived home from the Folsom supercharger yesterday with 50 miles remaining, having used 39.9kWh. This morning I had 28 rated miles (I charge at work, which is 7 miles down hill) but the trip meter still said 39.9kWh.

I think I lost more than the usual 10+ miles per night because it was recovering from the long drive.

 

[Jeff Miller]

I find it interesting that the trip meter doesn't record the vampire loss. I arrived home from the Folsom supercharger yesterday with 50 miles remaining, having used 39.9kWh. This morning I had 28 rated miles (I charge at work, which is 7 miles down hill) but the trip meter still said 39.9kWh.

I agree - vampire losses should be definitely be recorded by the car.

It seems like Tesla should easily be able to record and display is the total cumulative energy entering the car from the wall. This should be pretty much equal to what you'd record on a wall energy meter. In a sense this total is the most important number - it is what determines total fuel cost and car efficiency.

The total energy should then equal the energy used while the car is driving (what the Model S currently displays if I'm not mistaken) plus the vampire losses from the electronics and battery thermal management when the car is not being driven plus the excess energy required to charge the battery since recharging is not 100% efficient. It would be great if the Model S recorded and displayed somewhere all these numbers (total, driving loss, vampire loss, charging loss).

 

[markb1]

I took a trip on Saturday. I completed a range charge just before I left. When I got back home, the trip meter said I'd used 46.5 kWh. I plugged in to do a standard charge, and when it was done, the charge screen said it added 48 kWh. That's about 7.5 kWh unaccounted for. (I'm accounting for the difference in charge modes with my 60 kWh pack.)