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Effects of Winter on Tesla Battery Range and Regen

Published

10 years ago

November 24, 2014

Rob M.

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!

News

U.S. Secret Service in talks for armored cars with this automaker

The Secret Service says it’s still too early to know the future of a potential deal for these “highly-advanced vehicles.”

Published

9 hours ago

March 22, 2025

Zachary Visconti

Credit: Jeffrey Sauger (via GM)

The U.S. Secret Service has entered early discussions with one automaker about the potential supply of armored SUVs, as announced by the agency this week.

In a post on X on Friday, the Secret Service account posted that Director Sean Curran recently met with executives from General Motors (GM) to discuss a potential next-generation of armored SUVs. The post also included photos of a Cadillac Escalade SUV, along with a few of executives talking about and showing off hardware from the next-gen platform.

“Countering evolving threats require us to constantly explore new innovations and improvements to our armored fleet of protective vehicles,” the account wrote in the post. “Director Sean Curran met with GM executives to discuss advancements that could benefit the next generation of armored SUVs.”

Credit: U.S. Secret Service | X

Credit: U.S. Secret Service | X

Currently, U.S. President Donald Trump typically utilizes an armored Chevy Suburban to get around, and the Secret Service said that it isn’t yet clear when such a next-gen “presidential limousine” could be added to the fleet. The news also comes after GM CEO Mary Barra met with Trump last week, reportedly also to discuss armored SUVs.

READ MORE ON U.S. GOVERNMENT: This former Tesla engineer now heads a federal tech department

“We are too far out to speak to any specific costs or dates,” one Secret Service spokesperson told Reuters. “Our engineering, protective operations and technical security teams work for years to develop the state-of-the-art framework that is used to produce these highly advanced vehicles.”

Many in the thread also said that the Tesla Cybertruck could be a good option for the Secret Service, coming weeks after the U.S. State Department apparently canceled a potential $400 million Cybertruck order after it was widely reported on. State Department officials have since said that the figure listed in documents for the deal, which was first initiated under the Biden administration, were simply an estimate, and the Cybertruck has been removed from the broadly reported procurement list.

CEO Elon Musk also responded to the reports on X, suggesting that they were either misunderstood or false, noting that he was “pretty sure Tesla isn’t getting $400 million.”

“No one mentioned it to me, at least,” Musk added in the post.

The Cybertruck features a stainless steel exterior that has been touted by Tesla as being able to withstand bullets and other potential attacks. Tesla Cybertrucks have also been rolling out to some U.S. Police Departments in recent months, many featuring armored tune-ups from Unplugged Performance’s Up.Fit government and military fleet division.

Irvine PD unveils Tesla Cybertruck DARE program fleet unit

News

Tesla Powerwalls to help expand Virtual Power Plant in Colorado

Colorado’s Virtual Power Plant program is about to get even bigger, with the help of Tesla’s Powerwalls.

Published

11 hours ago

March 22, 2025

Zachary Visconti

Tesla’s Powerwalls are set to help expand a Virtual Power Plant (VPP) program in Colorado, as an announcement this week notes that the company will be partnering with two local energy providers.

In a press release on Thursday, utility provider Xcel Energy and resource management company Itron announced a partnership with Tesla to help expand the existing VPP in Colorado, dubbed the Renewable Battery Connect program. Itron will integrate its IntelliFLEX platform with Tesla’s Powerwall management system, and the partners plan to increase the number of batteries that can be used during times of peak demand, as managed by Xcel.

The IntelliFLEX Aggregator Distributed Energy Resource Management System (DERMS) is designed to let energy providers localize the management of distributed batteries, utilizing a combination of residential battery storage, solar energy, electric vehicle (EV) chargers and other management systems to help balance grid energy more efficiently.

“Our Renewable Battery Connect program creates a new VPP in Colorado and we’re proud to work with Itron and Tesla, who have proven to be trusted industry partners and align with our goals to strengthen the energy grid while maintaining reliability and advancing renewable energy,” said Emmett Romine, Xcel’s VP of Customer Energy and Transportation Solutions. “This collaboration will deliver renewable, solar energy when our customers need it most.”

Truly one of the most underrated benefits of having a Tesla Powerwall.🏡🔋
Because fluctuating electricity prices suck.pic.twitter.com/GwIvOB3F1y
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— TESLARATI (@Teslarati) February 27, 2025

READ MORE ON TESLA POWERWALLS: Tesla partners up to expand Virtual Power Plant program in Texas

Itron also says the IntelliFLEX system currently helps facilitate around three million distributed energy resource devices for 30 different utilities across the U.S. The company also says the tool will give Xcel more power to manage customers’ residential batteries to help stabilize local grids.

“Integrating our IntelliFLEX solution with Tesla Powerwall demonstrates a shared vision with a leading technology partner who is at the forefront of creating electrification solutions,” said Don Reeves, SVP of Outcomes at Itron. “Through this collaboration, we are excited to bring new capabilities to Xcel Energy as they embark on its energy transition journey.”

Tesla’s Powerwall home batteries have been utilized in markets around the world, effectively letting owners store and sell stored energy back to the electrical grid in times of peak demand, outages, and other peak use cases. This kind of distributed battery system is being piloted or run in a number of U.S. states, including California, Texas, and Massachusetts, and in a few other countries and territories.

The company currently builds Powerwalls at its Gigafactory in Nevada, and the facility in November celebrated building over 1,000 of the home batteries in a single day as it continues to ramp production. In October, Tesla also said that it had over 100,000 Powerwalls participating in its VPP programs worldwide.

Tesla shows off solar, Powerwall-backed display at Giga Berlin

News

Tesla quietly added this extra Sentry Mode feature to deter vandals

Tesla’s Sentry Mode gets another feature, set to add an extra layer of security against vandalism.

Published

13 hours ago

March 22, 2025

Zachary Visconti

Credit: Tesla

Amidst increased vandalism events against Tesla’s vehicles in recent weeks, the company’s Sentry Mode has increasingly been in the spotlight as a deterrent for criminal activity. As part of an update to its website this week, Tesla has also revealed a subtle addition to the recording system that should help deter vandals caught in the act.

Tesla’s Sentry Mode on Cybertrucks will soon play music at the maximum volume when the vehicle’s cameras detect activity, as detailed on the company’s redesigned Cybertruck web page this week and initially spotted by Not a Tesla App. The detail was quietly added to the Cybertruck web page, as part of the larger Sentry Mode suite of features that lets owners check out the external cameras on their electric vehicles (EVs) even when away.

“Enable Sentry Mode to monitor your unattended vehicle or trailer, and automatically activate the alarm, increase the touchscreen brightness and play music at max volume if a threat is detected,” Tesla writes on the Cybertruck page.

The music feature could use the Cybertruck’s superhorn and external speaker to play the music outside the vehicle for an even louder response to potential threats, though it’s not clear at this point whether the added feature will utilize the external or internal speakers. The music feature is also not detailed on Tesla’s web pages for other vehicles at this point, though it would be surprising to see it only available on the Cybertruck given that Sentry Mode is available across the company’s entire lineup.

You can also see the Sentry Mode image that appears on the touchscreen when activated below.

Credit: Tesla

READ MORE ON TESLA SENTRY MODE: Tesla is about to ship a fix to a big Sentry Mode issue

Tesla details the features from Sentry Mode in its owner’s manuals as follows:

When enabled, your vehicle’s cameras remain powered on and ready to record suspicious activity around your vehicle when Cybertruck is locked and in Park. Think of Sentry Mode as an intelligent vehicle security system that alerts you when it detects possible threats nearby.

If a threat is detected or the vehicle sensors determine there is a lot of jerky movement like when getting towed or shaken, Sentry Mode:

- Pulses the headlights.
- Sounds the alarm.
- Displays a message on the touchscreen that indicates cameras may be recording to inform individuals outside of the vehicles.
- Alerts you of the alarm on the mobile app.
- Saves footage of the event to a USB drive (if installed)

Earlier this week, CEO Elon Musk also said that Tesla was increasing security at the company’s stores, along with activating Sentry Mode on all vehicles at the company’s locations. Musk also said earlier this month that it could make its vehicles automatically honk at people who come near or touch the vehicle, which would take a similar approach to scaring off people potentially keying or otherwise vandalizing a Tesla.

Tesla has ramped up security and activated Sentry Mode on all vehicles at stores https://t.co/3HwUgE8ZoF
— Elon Musk (@elonmusk) March 20, 2025

Following a substantial uptick in protests and vandalism targeting Tesla’s vehicles in response to Musk’s recent actions at Trump’s inauguration and since with the newly created government efficiency, the Federal Bureau of Investigation (FBI) has begun looking into several of these incidents.

Additionally, President Donald Trump said that Tesla attacks would be categorized as “domestic terrorism,” even suggesting that some of those who have been recently arrested in these cases could be sent to prison camps in El Salvador, where the administration has recently been sending migrants.

“I look forward to watching the sick terrorist thugs get 20 year jail sentences for what they are doing to Elon Musk and Tesla,” Trump wrote in a post on his social media platform Truth Social. “Perhaps they could serve them in the prisons of El Salvador, which have become so recently famous for such lovely conditions!”