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Tesla Model S Has Bizarre 'Vampire-Like' Thirst For Electricity At Night
cartechboy writes "The Tesla Model S, for all its technical and design wizardry, has a dirty little secret: Its a vampire. The car has an odd and substantial appetite for kilowatt-hours even when turned off and parked. This phenomenon has been dubbed the 'vampire' draw, and Tesla promised long ago to fix this issue with a software update. Well, a few software updates have come and gone since then, and the Model S is still a vampire sucking down energy when it's shut down. While this is a concern for many Model S owners and would be owners, the larger question becomes: After nine months, and multiple software updates,why can't Tesla fix this known issue? Tesla has recognized the issue and said a fix would come, yet the latest fix is only a tiny improvement — and the problem remains unsolved. Is Tesla stumped? Can the issue be fixed?"
Is Tesla stumped? Can the issue be fixed? Tune in tomorrow — same Bat-time, same Bat-channel!
But on a serious note - I'm pretty sure the issue has something to do with this: http://sanctuary.wikia.com/wiki/Nikola_Tesla
Now known as Lestat model S.
That's the problem. The engineers at Tesla have the really expensive multimeters.
Tesla is renting the cars out at night using Google's self driving technology and Google maps to run a secret taxi service. That guy reported 10-15 miles of charge missing overnights, that could be a few fairs used to pay for more of Tesla's research.
Dear aunt, let's set so double the killer delete select all
No, because it's not using '180W'. It's using the equivalent of 180W draining for 24 hours. Compare with 180W draing for 5 minutes, the time component is important.
Right off the bat when he compares the Tesla's range estimate at the end of the day (when the batteries are warm) with the one the next morning (when the batteries are cold) I was already shaking my head. Fortunately the article later includes the explanation from the Tesla rep, but therein begins the pattern: long-winded article going on about this guy's half-assed attempts at figuring this out, punctuated by sensible explanations from the Tesla rep. The whole article could have been summarized thusly:
And why does he seem to lose more juice than the Tesla rep's estimate? (1) Tesla's estimate is likely an average and isn't specific to the cold overnight conditions this guy has (the system's drain on a cold battery will be harsher), and (2) he's measuring how much THE CHARGER is using in the morning, and he says himself that the charging system needs to warm up the batteries before charging, so he's measuring lost power PLUS the power needed to warm the system.
I'd look for heat.
That amount of energy drain will be making something warm.
The on-board systems continue to suck juice from the vehicle's batteries overnight because Tesla has temporarily disabled (or diminished) their sleep mode due to some issue waking them back up (incidentally, that makes this issue hardly mysterious or "bizarre").
Sometimes the simplest answers indicate someone didn't RTFA.
I used to think I'd have to drink blood or something to be a vampire, but no. I've now learned that since my stomach is full when I go to bed, and gets emptier while I sleep, leaving me hungry and in need of a little refuelling in the morning... that makes me a vampire!
Tesla Model S uses a proximity sensor to detect the key fob in your pocket and extend the door handle with a motor:
http://www.consumerreports.org/cro/news/2013/05/video-sci-fi-wizardry-of-the-tesla-model-s-doors/index.htm
To quote from an article:
"From the instant you walk up to the Tesla S and the door handles motor out of the door, you know this isn't going to be like any other car you've ever driven. You open the door and the air conditioner has fired up, and your music is already playing. You put your foot on the brake, shift into gear, and you are off and running. There is no âoestartâ button. When you arrive, you just get out of the car; it turns itself off and locks up as you leave."
Tesla originally had a sleep mode for the inboard computer that was supposed to consume around 1%/day. But they found that the sleep mode often resulted in the car not detecting the key fob. So they disabled it until they could patch it. Not surprisingly, it sucks a lot of power while its sitting in non-sleep mode waiting for someone to walk by with the right key fob. If they had stuck with a manual door handle and a push start button for the engine, then the idle power issue would never have come up. In any case, Tesla is working on it and will resolved it eventually.
I find this wrinkle hilarious, out of sympathy. I have never, EVER, in the course of using probably 10 laptops over the last 10 years, had one on which suspend/resume actually worked right. Many that worked a few times, or even a couple weeks, or that worked unless I used a docking station, or 3d acceleration, or WiFi. And yes, that includes my i7 MacBook Pro running OSX; plug and unplug the external display and network enough times, and sooner or later it will forget to wake up when you open the lid.
Again, I love it when non-engineers talk out of their ass. Even top-o-the-line Fluke's don't go over 10A. They all need current clamps which are just one side of a transformer coil to step that current down into a usable range. If you want to directly measure high currents without said clamp, then you're still toting around a big ass ammeter which are still fairly expensive since they contain quite a bit of copper to carry that load. You won't be using a handheld meter for sure.
In America, you have a warning sticker for that.
In Europe, we have common sense for that.
In America, you have a warning sticker for that.
In Europe, we have common sense for that.
In California, you may get cancer from that.
I know you joke but we've had some engineers truly stumped and raising all sorts of wonderful alarms due to this very issue. Fancy expensive multimeters with internal resistances in the >10s of GOhms. They've tested for dead on the cable and the cable measured some 70V. I went and got an ancient analogue meter and it measured zero. Naturally it was my meter that was "broken". So we made a bet. $100 that I put a 24V bulb on his 70V cable and it wouldn't even light up briefly.
Turns out the cable was picking up noise which presented a voltage to the very expensive meter, but we were talking about only microwatts. I was $100 richer and my ancient analogue meter got some real cred.
Had a similar issue on a 24V supply where one engineer was insisting that we didn't turn off the correct battery bank because he was still measuring 24V. Turns out that leakage current back from the other bank was causing the reading which again wouldn't have been a problem if he didn't have such a damn good multimeter.
No big mysteries here. Room for complaint that this issue hasn't been resolved quickly, though.
Your quote is from the original article from March. In the next link he talks about the latest November update, which reintroduced sleep mode.
That said, he's wrong that the latest update doesn't fix the problem. I own a Model S, and I went from losing about 5 miles off my rated range in 8 hours to losing about 1 mile per 14 hours. So, what's the difference between my car and his? Well, based on the pictures he posted, which has snow on the ground, he lives somewhere far colder than South Carolina, where I live. So his car is using more power for thermal management of the batteries.
But wait, you say. The article says, "It's a popular myth among Model S owners that much of the vampire power goes to keep the battery warm during cold nights. This is simply not true. According to Tesla, there is no thermal management of the Model S battery when the car is turned off and not charging--no matter how cold it gets."
True, guy. However, let's examine your testing methodology: "For each test, I charged the car up in the evening to its usual selected level (In my case, about 80 percent). Then I removed the charge plug. I allowed the car to sit unplugged overnight and on into the next day, until I needed to drive it. (Typically a span of 12 to 24 hours.) Before driving it, I plugged it back in to top off the vampire-depleted battery back to its original level. Then I checked the kWh-meter."
And...when you plug it in to charge it, the pumps come on, and they start heating up your battery for safe charging. There's your so-called vampire load. My car, in a warmer environment, doesn't have to spend as much energy doing that.
Furthermore, he says: "The three tests showed vampire losses of 2.3 kWh in 17 hours, 1.9 kWh in 23 hours, and 4.2 kWh in 18 hours...I can't explain the wide variation in the vampire draw over the three tests."
Maybe he should try correlating it with temperature.