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Effects of Winter on Tesla Battery Range and Regen
Winter conditions has begun to set in here in New England with temperatures not exceeding the 20’s. Thankfully I’ve already prepared my winter wheels and tires in advance so I’m not overly worried about the potential for snow, however I’m quickly learning the effects of winter on the battery and overall energy efficiency.
Cabin Temperature
Preheating the cabin temperature through the mobile Tesla Motors app.
The first order of business is making sure I’m comfortable when I get into the car each day. This means preheating the Model S cabin temperature through the Tesla App (if I happen to remember to) or, better yet, have it scheduled to automatically preheat via the VisibleTesla app.
My daily schedule looks something like this: VisibleTesla preheats the car 30 minutes before I enter and while it’s still plugged in from my overnight charge. This ensures I enter a warm car every morning with no affect on my range – the best of both worlds!
Leaving for work at the end of the day, however, is a bit more erratic so I usually use the Tesla App to preheat on an ad-hoc basis. I realize that this preheating will eat into my overall battery range, but I’m not overly concerned because I have plenty of range to spare even with a 100 mile commute each day. It’s well worth it for a little more comfort.
I enjoy turning on the air conditioner during the summer months but getting into a warm car in the dead of winter is even better!
Limited Regenerative Braking
Prior to the winter, the only times I have experienced limited regenerative braking (regen) was directly after performing range charges in anticipations of my Tesla road trip adventures. The Tesla battery does not have the capacity to receive additional energy (when at a 100% state of charge) thus it disables regenerative braking all together.
Winter months, however, bring a completely different experience with regen. When the Model S is cold it limits the ability to regen since the batteries need to be at an optimal temperature before it receives any additional charge.
A dashed yellow line appears on the center display indicating that regenerative braking is limited. If you’ve been accustomed to driving with regen on, this new behaviour (with regen disabled) will feel and drive very differently.
I found myself quickly rolling towards the cars in front of me as I instinctively ignored the brakes and assumed that the car would just come to a gradual stop by letting go of the accelerator pedal. That obviously didn’t happen with regen limited. You’ll need to use your brakes so be careful not to “over press” it as you quickly adjust to driving with brakes again.
This winter-induced form of limited regeneration lasts for a very long. I wasn’t sure if the lack of regen was isolated to the weather conditions for that particular day so I decided to log my results over a larger sample of several days.
Here’s what I noticed about the effects of winter on Tesla’s regenerative braking:
- There appears to be a linear easing off of the “regen cap” through the first 30 minutes. At 0 miles, when the car is just started, the amount of regen is capped at 20 kW.
- 25 minutes into my drive, the regen cap is loosened to 40 kW.
Graph depicting the amount of energy that can be regained through regen over time.
As you can see from some of my data points, it took me over 45 minutes of driving (30 miles covered) before the regenerative braking behavior was back to normal — that’s almost my entire drive home!
I’ve been experimenting with various approaches to avoid the regen capping. One of which is timing my overnight charge so that it completes right at the time I’m about to leave for work. This ensures that the batteries are at a good temperature, by the time I begin driving, and with no regen cap in place. Timing it perfectly can be tricky.There’s been a few occasions where my charge completed earlier than expected and as a result the batteries cooled off before I got to drive.Here again VisibleTesla can help, but it’s an area that I wish Tesla would address directly —
add a feature to allow users to specify the END time for a charge as opposed to the start time. The Model S should calculate when charging begins based on the set end time.
I’ve been experimenting with ways to reduce the after-work limited regenerative braking occurrences but since there’s no charging infrastructure at my work, I can’t pre-warm the batteries. I’ve even tried warming up the cabin temperature in advance to see if this would have an impact on regenerative braking but unfortunately it doesn’t.
Higher Energy Use
Cold weather definitely affects energy use on the Model S. My tires, while great for winter, are less efficient — they’re not the low rolling resistance tires that came with the Model S. I’m also using extra energy for warming the cabin (despite my chilly 66 F year-round cabin temperature setting). The Model S is also using extra power when managing the battery temperature.
Prior to winter my average energy consumption was around 300-315 kWh/mi but now I’m averaging 350-365 kWh/mi or approximately 16% more energy used than summer months. I’m also using my brakes more during the winter, as a result of the limited regenerative braking, so that will also introduce more wear and tear.
One piece of advice from Tesla is to use seat heaters to warm yourself up over cabin heat. The seat heaters apply heat directly to your body and thus a more efficient use of energy. If you have your cabin temperature set at 72 F , try reducing it to 68 F and use your seat heaters to warm yourself up.
I’m sure I’ll be uncovering a lot more tips and interesting findings over the next few months especially as the snow storms start blowing in and temperatures dip into single digits! Stay tuned!
Elon Musk
Elon Musk and Tesla AI Director share insights after empty driver seat Robotaxi rides
The executives’ unoccupied tests hint at the rapid progress of Tesla’s unsupervised Robotaxi efforts.
Tesla CEO Elon Musk and AI Director Ashok Elluswamy celebrated Christmas Eve by sharing personal experiences with Robotaxi vehicles that had no safety monitor or occupant in the driver’s seat. Musk described the system’s “perfect driving” around Austin, while Elluswamy posted video from the back seat, calling it “an amazing experience.”
The executives’ unoccupied tests hint at the rapid progress of Tesla’s unsupervised Robotaxi efforts.
Elon and Ashok’s firsthand Robotaxi insights
Prior to Musk and the Tesla AI Director’s posts, sightings of unmanned Teslas navigating public roads were widely shared on social media. One such vehicle was spotted in Austin, Texas, which Elon Musk acknowleged by stating that “Testing is underway with no occupants in the car.”
Based on his Christmas Eve post, Musk seemed to have tested an unmanned Tesla himself. “A Tesla with no safety monitor in the car and me sitting in the passenger seat took me all around Austin on Sunday with perfect driving,” Musk wrote in his post.
Elluswamy responded with a 2-minute video showing himself in the rear of an unmanned Tesla. The video featured the vehicle’s empty front seats, as well as its smooth handling through real-world traffic. He captioned his video with the words, “It’s an amazing experience!”
Towards Unsupervised operations
During an xAI Hackathon earlier this month, Elon Musk mentioned that Tesla owed be removing Safety Monitors from its Robotaxis in Austin in just three weeks. “Unsupervised is pretty much solved at this point. So there will be Tesla Robotaxis operating in Austin with no one in them. Not even anyone in the passenger seat in about three weeks,” he said. Musk echoed similar estimates at the 2025 Annual Shareholder Meeting and the Q3 2025 earnings call.
Considering the insights that were posted Musk and Elluswamy, it does appear that Tesla is working hard towards operating its Robotaxis with no safety monitors. This is quite impressive considering that the service was launched just earlier this year.
Elon Musk
Starlink passes 9 million active customers just weeks after hitting 8 million
The milestone highlights the accelerating growth of Starlink, which has now been adding over 20,000 new users per day.
SpaceX’s Starlink satellite internet service has continued its rapid global expansion, surpassing 9 million active customers just weeks after crossing the 8 million mark.
The milestone highlights the accelerating growth of Starlink, which has now been adding over 20,000 new users per day.
9 million customers
In a post on X, SpaceX stated that Starlink now serves over 9 million active users across 155 countries, territories, and markets. The company reached 8 million customers in early November, meaning it added roughly 1 million subscribers in under seven weeks, or about 21,275 new users on average per day.
“Starlink is connecting more than 9M active customers with high-speed internet across 155 countries, territories, and many other markets,” Starlink wrote in a post on its official X account. SpaceX President Gwynne Shotwell also celebrated the milestone on X. “A huge thank you to all of our customers and congrats to the Starlink team for such an incredible product,” she wrote.
That growth rate reflects both rising demand for broadband in underserved regions and Starlink’s expanding satellite constellation, which now includes more than 9,000 low-Earth-orbit satellites designed to deliver high-speed, low-latency internet worldwide.
Starlink’s momentum
Starlink’s momentum has been building up. SpaceX reported 4.6 million Starlink customers in December 2024, followed by 7 million by August 2025, and 8 million customers in November. Independent data also suggests Starlink usage is rising sharply, with Cloudflare reporting that global web traffic from Starlink users more than doubled in 2025, as noted in an Insider report.
Starlink’s momentum is increasingly tied to SpaceX’s broader financial outlook. Elon Musk has said the satellite network is “by far” the company’s largest revenue driver, and reports suggest SpaceX may be positioning itself for an initial public offering as soon as next year, with valuations estimated as high as $1.5 trillion. Musk has also suggested in the past that Starlink could have its own IPO in the future.
News
NVIDIA Director of Robotics: Tesla FSD v14 is the first AI to pass the “Physical Turing Test”
After testing FSD v14, Fan stated that his experience with FSD felt magical at first, but it soon started to feel like a routine.
NVIDIA Director of Robotics Jim Fan has praised Tesla’s Full Self-Driving (Supervised) v14 as the first AI to pass what he described as a “Physical Turing Test.”
After testing FSD v14, Fan stated that his experience with FSD felt magical at first, but it soon started to feel like a routine. And just like smartphones today, removing it now would “actively hurt.”
Jim Fan’s hands-on FSD v14 impressions
Fan, a leading researcher in embodied AI who is currently solving Physical AI at NVIDIA and spearheading the company’s Project GR00T initiative, noted that he actually was late to the Tesla game. He was, however, one of the first to try out FSD v14.
“I was very late to own a Tesla but among the earliest to try out FSD v14. It’s perhaps the first time I experience an AI that passes the Physical Turing Test: after a long day at work, you press a button, lay back, and couldn’t tell if a neural net or a human drove you home,” Fan wrote in a post on X.
Fan added: “Despite knowing exactly how robot learning works, I still find it magical watching the steering wheel turn by itself. First it feels surreal, next it becomes routine. Then, like the smartphone, taking it away actively hurts. This is how humanity gets rewired and glued to god-like technologies.”
The Physical Turing Test
The original Turing Test was conceived by Alan Turing in 1950, and it was aimed at determining if a machine could exhibit behavior that is equivalent to or indistinguishable from a human. By focusing on text-based conversations, the original Turing Test set a high bar for natural language processing and machine learning.
This test has been passed by today’s large language models. However, the capability to converse in a humanlike manner is a completely different challenge from performing real-world problem-solving or physical interactions. Thus, Fan introduced the Physical Turing Test, which challenges AI systems to demonstrate intelligence through physical actions.
Based on Fan’s comments, Tesla has demonstrated these intelligent physical actions with FSD v14. Elon Musk agreed with the NVIDIA executive, stating in a post on X that with FSD v14, “you can sense the sentience maturing.” Musk also praised Tesla AI, calling it the best “real-world AI” today.
Elon Musk and Tesla AI Director share insights after empty driver seat Robotaxi rides
Starlink passes 9 million active customers just weeks after hitting 8 million
