Tesla Model S Battery Drain Issue Fixed 239
cartechboy writes "Does the Tesla Model S suck down power even when the car is switched off? Recently, a tweet to Elon Musk with an article saying so sparked the Tesla CEO's attention. He tweeted that it wasn't right and that he'd look into the situation. Then a few hours later, he tweeted that the issue had to do with a bad 12-volt battery. Turns out Tesla had already called the owner of the affected car and sent a service tech to his house to replace that battery — and also install a newer build of the car's software. Now it appears the 'Vampire Draw' has been slain. The car went from using 4.5 kWh per day while turned off to a mere 1.1 kWh. So, it seems to be solved, but Tesla may either need to fix some software, or start sending a few new 12-volt batteries out to the folks still experiencing the issue."
Re:And, Folks, stay tuned.. (Score:5, Interesting)
Actually, it's shockingly high. I'm a Tesla fan, but this seriously makes me wonder what's eating up all that energy while the car is supposed to be "off".
The Tesla is not the only car out there with "all kinds of gizmos built into it": every high-end luxury car, from the likes of Mercedes, BMW, Cadillac, etc., is loaded with electronic accessories. However, all those cars run on gasoline engines, with a standard 12V battery to keep things alive when the car is "off". No regular car would be able to start its engine in the morning if it were powering a 40W light bulb all night.
So what exactly is the Tesla doing with all that power? Even if it's keeping a WiFi connection alive, that shouldn't take much power: my little smartphone can do that for days with a puny little 5.6Wh battery. Are they running the main computers at full power? It really shouldn't be that hard to put them into sleep states when the car is off. It sounds like maybe they badly architected the computers in this car, so that they could never go into power-saving sleep states and still keep the WiFi/3G connection alive, something every modern smartphone can do with ease.
Re:$80k car, $10 cutoff switch? (Score:5, Interesting)
One of my favorite features of my Nissan Leaf is that I can turn the air conditioning or heater on from a phone app. I can also check the state of the batteries and the time remaining until it fully charges. So even in standby, electric cars are doing a decent amount of stuff.
Re:That's shocking! (Score:5, Interesting)
And the fact that the "fixed" Tesla still sucks up enough power to drain the battery in any other car overnight, every night...
I'm kind of wondering if "sucks up" is really the right verb to be using here. I mean, the article's author notes that the battery pack has a nominal 85 kWh capacity. Losing 1.1 kWh in 24 hours (note, not just "overnight") from a fully-charged battery pack is a shade less than 1.3% of the total capacity per day; if it maintained that rate of discharge, it would drain the battery pack in about 2.5 months.
The question I have, then, is how much of that consumption is replenishment of unavoidable self-discharge from the batteries, versus actual electricity used to power the various onboard electronics packages. That is, even if you physically cut every connection between the car and the battery pack in the evening, how much would the charge need to be topped up come morning?
In every Tesla thread I mean to ask... (Score:3, Interesting)
What is the US energy mix? Is a Tesla better for the environment than a small petrol driven car? What about the embodied energy of a Tesla vs. a conventional car?
I know here in Australia where we burn brown bloody coal an electric car produces more emissions than a V6.