Tesla released a software update for its much-praised Model S electric car recently that should help owners eek a few extra miles out of each charge of the car’s batteries.
According to CleanTechnica, the Tesla Model S loses about eight miles of driving range for every day it is parked without being plugged into a charger. That equates to 56 miles per week or 240 miles per month. In the Model S with the larger 80 kWh battery pack, this means the Tesla loses about 2.6% of its charge every day it is parked off-charger. And as The Green Optimistic notes, if you park a fully-charged 40 kWh Tesla Model S for a month without plugging it in, it will be stone dead.
The loss comes from parasitic drain, something common to most electronic devices nowadays, from your DVD player to the computer or mobile device you’re using to read this. Much like those devices, the Tesla Model S doesn’t truly turn all the way “off” when parked. Some battery power is used to maintain settings of the car’s electronic features, including the touchscreen center stack and electronic instrument panel.
According to Tesla’s notes on the software update release, “With this release, Model S will power off the display and vehicle electronics each time you exit, transitioning to a ‘sleep’ state. When you return to Model S, you’ll note a modest increase in the time it takes the touchscreen and instrument panel to wake from this energy-saving state. Model S will initiate the startup process the moment the key is recognized nearby. You can only begin driving once both displays are ready.”
The change will reduce parasitic losses in Teslas parked without access to charging facilities. However, if you’re the type to store your keys in or near the car, you may not see any benefit, as the car will “wake up” from its “sleep mode” when it detects the key is nearby. (And hopefully if you’re keeping your keys in your Tesla Model S, said Model S is securely locked away in a private garage, for your sake!)
While some sources referenced a press release on the software update, a Tesla Motors media contact said no such press release was issued and suggested instead that the details came from software release notes issued to owners to explain to them the features of the software update.
Like all Tesla software updates, Tesla owners should expect the update to download to the car’s system anytime the car has reliable 3G or WiFi connectivity. Installation of the updates– which will “brick” the car and make it unusable for a short period of time– can be scheduled to take place at a later time when the owner is sure the car will be parked for a long stretch.