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An exclusive look at Tesla's extreme cold testing facility

Can you really drive an electric car 365 days a year if you live in a land with real winters? We headed to Alaska to find out.

Nick Miotke/Roadshow

Electric cars are often perceived as terrible choices for winter driving. As an EV owner who lives in the north, I don't mind saying that reputation is generally well earned. Most early EVs, and plenty of current ones, suffer major range penalties as soon as ambient temperatures drop below the comfort zone of their battery packs.

And then there's the weight of those packs. An electric car's unusually high mass sitting on low-rolling-resistance "all-season" tires creates a recipe for disappointment when things get even a little bit slippery. 

Watch this: Sliding around in Teslas at the company's Alaska proving ground

Of all the EV manufacturers out there, has suffered the brunt of this chilly criticism. In the court of public opinion, Teslas have been deemed cars made in California for Californians: fair-weather, emissions-free rocketships best buttoned up and put away for the winter. That reputation was only reinforced when the current wave of Model 3s got their first taste of the cold, resulting in a swath of complaints about frozen door handles and stuck windows

But is that reputation deserved, or do we hear the most complaints about Teslas because, frankly, Tesla owners are the most vocal motorists on the planet? To find out more about just how well the company's machines handle less temperate conditions, we traveled to Alaska to put every one of the company's current production machines through their paces on snow and ice -- and have some fun while we were at it. 

Tesla Model 3 barrels through the snow in Track Mode

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Getting there

Tesla's cold-weather testing takes place on a secure facility near Delta Junction, Alaska. It's about a 2-hour drive down from Fairbanks, the closest piece of civilization for hundreds of miles around. Tesla engineers have been testing here for years, but this is the first time any journalists have been allowed to come film what they do all the way up there.

I left Fairbanks in a P100D fitted with a set of Pirelli Winter Sottozero tires, the kind of soft and grippy rubber that I was thankful for when the snow started falling. Temperatures were hovering around 10 degrees Fahrenheit for my early morning departure -- which in retrospect wasn't all that early, but certainly felt that way thanks to the complete absence of daylight. This time of year, the sun doesn't start making its presence known until close to 10 in the morning, taking a leisurely swing just above the horizon before winding down again by about 2 in the afternoon.

The nearly full Model S showed 314 miles of range on the clock when I pulled out for the 110-mile trip down. The drive was a mixture of highway and secondary roads, but long and straight secondary roads with 65 mph limits that tax an EV aerodynamically just like a freeway would. More taxing, though, were the conditions. Blinding snow often dropped visibility to nil while the thin, packed layer of ice on the roads made for a treacherous drive.

Still, I was quite comfortable in the Model S, heated seat and steering wheel put to good use. The Pirellis proved more than capable on the changing conditions and I was thankful for the large navigation display that told me when I needed to slow down for sharp turns ahead -- even when I couldn't see them. A heads-up display would have made it even easier, though. 

Tesla Alaska Testing Facility

Dashing through the snow...

Nick Miotke/Roadshow

Despite all that I completed the drive in 2 hours without a single pucker-inducing moment, though I did get a bit of a fright (and a cracked windshield) when a plow passing in the opposite direction showered the car with gravel.

After 110 miles, the Model S showed 50 percent charge remaining and an optimistic 157 miles of indicated range. Based on my results for the drive down, that theoretically would have just given me enough to turn around and head back up to Fairbanks. As a reminder, the Model S P100D is EPA-rated for 315 miles of range. 220 miles is a significant drop by any measure, but it can't just be blamed on a cold battery.

Softer, more aggressively treaded snow tires reduce efficiency, and the simple fact that the car was sliding around on the road drops its range, too. These are factors that impact cars with internal combustion engines as well, dropping fuel economy by 12 percent on average, according to the EPA.

In the Tesla, it was close to a 30 percent drop in ultimate range, and while it's impossible to know how much of that came down to the tires and conditions versus how much was purely due to temperature and battery chemistry, I do want to put the car's effective range in perspective. While I hate to be cruel to Jaguar's very compelling EV, the real-world, 220-mile range I observed on the Model S P100D on a 10-degree Alaska day falls just short of the 234 miles of EPA-rated range for the in ideal conditions.

Tesla Alaska Testing Facility

Acres and acres of corduroy, ripe for sliding.

Nick Miotke/Roadshow

The facility

You don't have to look far to find the middle of nowhere when visiting Alaska. That said, Tesla's Alaska proving grounds is definitely getting there, a sprawling facility mostly contained within a giant, asphalt oval. On that oval, and within its infield, Tesla engineers have at their disposal groomed snow and ice surfaces, a series of snowy handling courses, iced hills with numerous gradients, plus a skidpad that's big and slick enough to host a round of the NHL playoffs -- though the crowd would struggle to get past security.

Tesla isn't the only manufacturer to test here -- the military tests tanks, APCs and the like on these same grounds -- but Tesla has requested and performed extensive modifications to the location, such as creating a new handling course with enough elevation changes and tricky turns to challenge a WRC car, never mind a 5,500-pound SUV.

I got to drive it all and was left with the overwhelming impression that Tesla's test engineers are a pretty lucky crew, with access to the ultimate low-grip playground all day, every day, the only penalty being its frigid and remote location.

And while handling and safety of course are a major part of the equation, Tesla tunes the HVAC behavior of its cars here as well, honing their ability to perform efficiently in extreme conditions.

Tesla Alaska Testing Facility

A steep hill with half the car on ice is a real test of the Model X's all-wheel drive.

Nick Miotke/Roadshow

Keeping it safe

The Model S and X, while very different machines, share a common trait when it comes to low-grip testing: safety is paramount. Both can be fun to drive, but their stability systems keep the drivers on a pretty short leash. Step out of line, do something the car doesn't like, and it'll drastically cut power and do everything necessary to keep you safe.

The best place to test this was on the massive snow field, just off the back straight of the oval. That means you can easily drive into snow at triple-digit speeds if you're feeling randy. With a laptop and a few clicks, one of Tesla's engineers shut off all the car's stability systems and invited me to do an emergency lane change at 65 mph, the sort of thing you may have to do in Alaska when encountering a wayward moose who's on the hunt for some trimmed greens.

With everything off, I cut onto the freshly groomed field of snow at 65 mph and jerked the wheel left and right and then was instantly thrown into one heck of a tank slapper. The car swerved back and forth as I frantically sawed at the wheel to keep up. I tried this maneuver a number of times and maybe caught it twice, but that's with a decade of high-speed ice driving experience at my disposal. While I mean no offense to your average Model S owner, your average Model S owner would have spun every time.

Re-enabling the car's stability and traction controls took a quick reboot and then I went and tried it again. Same speed, same field of snow, and try as I might I couldn't get the car to spin. I yanked the wheel left and right with all the finesse of a thoroughly endorphin'd Crossfitter and yet the car always kept itself inline, moving quickly enough to miss the imaginary moose, then calmly settling itself. 

The car does this through a combination of active braking and torque vectoring. When the car detects a skid, thanks to wheel speed and other sensors, it instantly begins to mitigate those slides by automatically braking individual wheels to pull the nose inline. The car can also modulate the amount of torque at the front and rear axles to maximize grip that way, resulting in a car that, even on 2 inches of loose powder, would not go around.

It's a similar approach to helping on steep, icy hills. None of Tesla's cars have proper locking or limited-slip differentials, instead relying on open differentials. Open diffs, which distribute power to the left and right wheels at an axle, are simple in execution and efficient in operation. However, when grip is limited, all those advantages go out the window. When one wheel or the other loses grip, an open differential allows that side to just spin wildly, sending no power at all to the wheel that actually has traction. 

In other words, on the ice, open differentials are pretty much the worst. 

Tesla Alaska Testing Facility
Enlarge Image
Tesla Alaska Testing Facility

Tesla's cold-weather testing facility is like a low-grip playground.

Nick Miotke/Roadshow


Tesla mitigates this by using what's often called an e-differential, relying on the car's brakes to slow down the spinning wheel, sending power across the axle. To demonstrate this, Tesla's engineers took me to the hillclimb portion of the proving grounds. Each of the hills, with gradients ranging from 10 percent all the way up to 60, has a strip of groomed ice in the center.

Tackling the 30 percent hill with a , positioning the left tires on the ice, resulted in a slow and occasionally unnerving but ultimately clean ascent. With the e-differentials disabled (again, not something you can do at home), the thing started the climb, spun its tires, and then promptly (and rapidly) skidded backwards down the hill.

Having a blast

I want to be totally clear that, while impressive, the above testing and results are in no way novel to Tesla. Plenty of other manufacturers like Audi and BMW and use similar stability control systems and e-differentials to give their cars superhuman abilities on snow and ice. I could have done the same imaginary bit of moose-slaloming in an A8 or an  and I would have had a similarly safe result.

However, while all manufacturers want their cars to be safe when the going gets slippy, few go the extra mile to make their cars fun. That is where the differentiates itself from its two stablemates. While Model 3 will do much the same tricks to keep you from spinning as Models S and X, its envelope of allowable slip is broader. 


That's true on even a base Model 3, but Performance with Track Mode takes it to another level. In Track Mode, the Model 3 will let you hang the tail way, way out, getting some properly lurid drifts going before it cuts the fun. Yes, it will cut the fun if you get things too far out of shape, killing the car's power and automatically deploying the brakes at the appropriate corner. But, the car gives you an awful lot of rope to hang yourself with before it kindly and reliably steps in to lift the noose from your neck. 

On the skidpad and on the tricky handling circuit I rarely felt like the car was preventing me from what I wanted to do, enabling tricky maneuvers like the Scandinavian flick, where you rely on weight transfer across the car to pivot around a tight turn. To do this you need to slide the car in not one but two directions, first away from the turn and then into it. Any hint of stability control would ruin the flow and kill the maneuver, yet lap after lap in the Model 3 it was no problem at all.

By building the Model 3's control software in-house, Tesla's engineers have even more ability to vector torque from front to rear both under acceleration and regenerative deceleration. This means the car can react more quickly and more precisely, again letting you push it that much further before cutting in.

Tesla Alaska Testing Facility

Few better ways to ride off into the sunset.

Nick Miotke/Roadshow

Exhilaration

While I've always respected what Tesla was trying to do with the Model 3, I haven't always been that car's biggest fan. But, after a day of sliding one around on the snow and ice, I was absolutely blown away. Having this much fun on the ice typically requires the pulling of fuses -- or at least a complex series of button presses to disable all the safety systems. The Model 3 is an absolute blast with everything left on.

Yes, I still wish Tesla would enable me to disable everything on my own, but the company is actually working on something that might be even better: an enhanced Track Mode that will let you manually adjust the torque split between the front and rear axles. That sounds like a dream to me for a fun day on the ice. The only thing missing will be a proper, mechanical handbrake.

And what about the more specific concerns raised about the Model 3's freezing door handles and stuck windows? Tesla quickly addressed the window issue with an update, but as ever I think a little perspective is important here. Back in 2002, my first new car also had door handles that stuck and windows that wouldn't go down in the cold. Additionally, it suffered whiplash-inducing clutch shudder on chilly mornings. It even leaked fuel when the temperatures were below freezing. That new car? It was a WRX, from a company that's been making some of the planet's best winter cars for decades.

Every new model has some teething problems. It's how the company reacts that's the important thing.

Tim Stevens Former editor at large for CNET Cars
Tim Stevens got his start writing professionally while still in school in the mid '90s, and since then has covered topics ranging from business process management to video game development to automotive technology.
Tim Stevens
Tim Stevens got his start writing professionally while still in school in the mid '90s, and since then has covered topics ranging from business process management to video game development to automotive technology.

Article updated on January 4, 2019 at 5:00 AM PST

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Tim Stevens Former editor at large for CNET Cars
Tim Stevens got his start writing professionally while still in school in the mid '90s, and since then has covered topics ranging from business process management to video game development to automotive technology.
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