EXCLUSIVE: Can a 2019 Tesla Model S Make it from SF to LA on One Charge?

Tesla’s flagship Model S sedan blindsided the industry as the upstart winner of the 2013 MotorTrend Car of the Year award—largely due to its previously unheard-of long-distance driving range from its battery pack. Until then, electric vehicles were fortunate to reach triple-digit miles on a single charge. Tesla obliterated that “range anxiety” myth, then added Superchargers to refute the “it’ll take all night to recharge” shortcoming.

But the competition is catching up in EV performance and technology, and seven years is an eternity without a complete redesign. Model S sales are starting to slump.

The Tesla-sphere has been in full speculation mode about what’s coming next: a new Model 3–like interior? Likely. But the cryptic invitation we received from Tesla PR only says this show-and-tell is about an improvement in range, plus a chance to demonstrate it by attempting to drive it from Tesla’s Fremont factory, in the Bay area, to the Hawthorne Supercharger station in front of Tesla’s design studio in L.A. I google it: 365 miles. Without recharging.

Whew. Sometimes, range anxiety is having your electric car able to drive too far. Bear in mind, there aren’t a lot of gasoline-fueled luxury cars that make the San Francisco to Los Angeles run on one tank. Now Tesla is claiming its updated EV flagship can do it.

After bypassing Elon Musk’s Autonomous Technology event for Wall Street types happening at the same time, we head into a small meeting room with a white board on one side and three guys already seated at a table. One of them, Lars Moravy (vehicle engineering, chassis), I know from a comparison of the Model 3 Performance with Track Mode at Willow Springs; the other two are Vineet Mehta (systems modeling and cell technology) and David Zhang (Model S/X program lead). It’s a busy day, and they want to get straight to the point of how the Tesla can now make this unprecedented commute.

“It’s getting the Model 3’s larger 2170-size cells?” I ask. “No, the battery is unchanged” they reply. “Same battery?” I tilt my head. “Same battery,” they repeat. “It’s not bigger?” “It’s the same battery” they say again. “But its range is going from what to what?” I ask. “The Long Range goes from 335 miles to range to 370. In general, 10 to 12 percent more.”

In fact, the drivetrain is fundamentally unchanged except for one bullet-point difference: its existing front drive unit is replaced by a repackaged version of the Model 3’s more efficient rear one. But that’s one of those easy explanations that obscures the actual answer. They tick through a few of the announced battery sizes and ranges for European EVs headed our way, and their ratios are universally terrible. The reason why, the trio emphasizes, is because they’re not treating their cars as synergistic wholes.

The Model 3’s motor is a permanent-magnet type, which is more efficient than the induction one it replaces. Back when Angus McKenzie and I visited Fremont in 2011—then an abandoned shell of a factory—Musk walked us past some motors they were hand-assembling, and I remember asking, “Why are these induction motors? Aren’t they less efficient?” “The difference isn’t much” he replied “And we avoid expensive magnets.”

Tesla’s skill at cost-analyzing an EV as a total system is colossally more sophisticated. The efficiency of every part is weighed against the cost of battery cells, and now, that analysis tilts in favor of the permanent-magnet motor being used on the front axle. I ask, “Doesn’t the permanent-magnet motor create drag when its power is not needed? An induction motor can be switched off, right?” True, but in light load conditions, the Model S is a front-wheel-drive car; the rear motor engages for extra power. So the front unit is never really idle. It’s either making power, regenerating it under braking, or idle at a stop.

A big diagram is projected on a screen. It’s the flow of energy entering the Model S and then how it’s gradually divided and consumed. It looks like a river and its tributaries, but in reverse. We see kW-hr going in, branches listed as aero losses, tire drag, etc., heading out. The Model S’ brain trust points to these branches and explains how conventional car companies ask their suppliers for their best, most efficient parts at the lowest prices, and then assemble them. Tesla intricately comprehends the whole car as a system of energy trade-offs. They lead me downstairs, into the battery lab, to see some examples.

Amid the “don’t touch” cables, shaker tables, monitors of blinking lights, and even a glass container of bubbling clear liquid (what’s that?) I’m shown tires. Tires? Pairs of current and new Model S tires, for both the Performance and Long Range versions, side by side. Lars points out the new tread patterns, changes in the multiple rubber compounds employed across the tread making them more efficient, and their lightness. He hands me the current and new wheels’ bearings. Turn them: The new one is noticeably easier to twirl. The costs of making tiny improvements to such seemingly unrelated details are constantly weighed against one another other and their impact on battery size and driving range.

Hmm, so if its battery is unchanged, is the Model S getting the new “V3” 250-kW Supercharging rates? There’s an awkward pause. “Not at this time” is the careful answer, but the car can handle a 200-kW Supercharging rate. That leaves the cheaper Model 3 (which was designed for V3) with a charging advantage. The allying counter-argument is that the current Superchargers are set to rise from 120 kW to 145 or 150, reducing the Model S battery’s charge time from 37 minutes to 26. And with 370 miles of range, you’re reducing how often you’ll stop anyway, and not stopping is quicker than the fastest charging, right?

Before heading to Fremont to start our trek south, we walk outside and belt into the latest Model S Performance version (Model 3 front motor, the existing large rear motor) for a hot lap around Palo Alto.

As the development engineer charges through corners, he reels through technical descriptions of every road irregularity and how the car is making them disappear. He notices everything—at one point exclaiming, “Flying squirrel! Did you see that?” This is a part of the Model S’ update wasn’t on my radar at all.

Its two key components are the air suspension’s four-corner adjustable damping and also the governing software that sounds suspiciously like Track mode. “That’s because it’s the same team that developed it.” Although the ride has been altered—stiffer rear springs and softer fronts so the car undulates more as a whole reducing pitching—the software is fast-retuning the suspension in response to an array of sensors. Whereas other systems use “look-up tables” to guesstimate setting adjustments, this, like Track mode, is running a real-time physics model and comparing the results to its predictions.

Before, ride height was determined purely by speed, lowering the chassis as velocities rose. Now it’s predicted by the road’s speed limit data, imbedded in the maps. The driver wiggles the steering wheel from its straight-ahead position. On-center feel is improved by quickly stiffening the appropriate corners of the car, raising the load on those tires. That’s when the wider width of the tread’s center rib comes into play. We’re really hauling, the car seemingly repaving the road as we arrive, when I mention, “It’s amazing that any sedan can do this, let alone a 7-year-old one.” Lars corrects me. “That’s because this isn’t the same car. It’s been constantly changing. For instance, these are the car’s third different lower front A-arms.”

At Fremont, the place is bustling like Main Street at Disneyland. People are milling in the showroom; tours are assembling and heading into the factory. We set up a quick video shot in the parking lot with the Long Range sedan we’ll be taking, and a security guy asks what we’re doing. He’s shooed away with a curt, “Elon says it’s OK.”  Remember that if you ever visit Fremont.

We’re told to set the climate control at 72, fan speed at 2, drive at the speed limit, and on the freeway to keep between 65 and 70 mph. We unplug the charging cable, I buckle into the front seat, and our video producer hops in back. The Tesla’s screen says the car has 370 miles of range.

Surprisingly, the nav system plots our route down the 101, over the steep Highway 152 pass, and dumps us onto Interstate 5, with its famous obstacle, the Grapevine, which is basically a mountain where it sometimes snows at its summit in the winter. “Is this really the best way?” I ask, thinking that following Highway 101 all the way along the coast, with its relatively gentler grades, would be less of a range challenge. “Just follow the map,” we’re told. (A quick side note: Technically, we are not driving from San Francisco to Los Angeles. We’re leaving Fremont, which is at the same latitude as Redwood City, about 26 miles south of San Francisco. But it’s still technically the Bay Area, which is what really matters in this test.)

At first, I’m being careful. Every drop in the battery level briefly scares me. Not only are we not recharging, I’ve decided to try it non-stop, too—zero pit stops into roadside rest areas—to avoid any possible losses. Tesla said that sort of bladder-busting measure is unnecessary, but hey, let’s see how far we can make it? Video copywriter Noah Dates in the back seat reluctantly agrees, as do the guys in the photo/video chase vehicle (though I’m sure they’re lying).

Most hypermilers do their best work alone to maximize range. With Noah in back, I already am suffering a 180-pound weight penalty, which in a test like this could prove crucial. Tesla says not to worry. To me, it’s also a more realistic test of a couple making a run between California’s two largest cities. Also, Tesla PR has been monitoring the weather. There will be a headwind as we head south. They express concern that it could affect the test. They want us to go for it, but add they can come fetch us if things get tight.

On the climb up the 152, I’m following chugging trucks in the right lane, but once we’re on the 5, I’m noodling between the super-fast left lane and the slowish semis to the right, being conservative and only passing when I can with normal acceleration. But driving between 65 and 70 mph on the I-5 is pretty much impossible. I’m driving pretty much like every other normal road warrior on this stretch.

All along the way, I’ve been using Navigation with Autopilot and wondering how things are going at that Autonomous event up in Palo Alto. This system not only provides radar-based adaptive cruise control but also suggests lane changes to pass when the side cameras say the coast is clear (just tap the turn signal). It’s pretty great—when a pickup merged from the right, it saw it and slowed; only once did I wonder about an approaching car and overrule its lane change with a tug back at the steer wheel.

And then we came upon a semi truck. We automatically changed lanes to pass the big rig, and as we got alongside, I realized it was actually a Tesla Semi doing testing at the same time. We radioed the photo car to find us (they were stopped somewhere, “getting something to drink”). In all my hand gesticulating, I’d loosened my grip on the steering long enough for the Autopilot to scold me and shut down. Geez, this is ironic. But I deserved it. My bad. Unfortunately, the only way to get on its good side again is to do a stop-and-go penalty, and we’re not stopping—right, Noah? He nods. From here on out, I have the pilot the car myself. What is this world coming to?

At the 270-mile point, we’re sitting pretty with a predicted 8 percent of battery left by the time we get to Hawthorne. But this is also the ramp up into the Grapevine and the 4,144-foot summit of the Tejon Pass. I remember being at the introduction of the prototype of the GM EV1—a car called the Impact—and a reporter asking GM President Roger Smith if it could make it over the Grapevine on a single charge. He and the engineers were silent. Now here I am starting the grade at 30 percent of the Model S’ battery remaining. This is simply amazing.

As we pass Magic Mountain, Noah and I consider stopping for some rides but agree that Tesla wouldn’t find that funny. So we glide down into L.A. traffic and eventually grind through to reach SpaceX headquarters, on the corner of Crenshaw Boulevard and Jack Northrop Drive.

As we pull into the Supercharger stall, our elapsed time from the Bay Area stood at 6 hours, 11 minutes, 359 miles. With 83 kWh used, we had 11 percent of the battery remaining—which equates to 41 more miles at the rate I was going. Right at 400 miles if you add it up. Had I continued down the I-405, I could have driven on to my abode in Costa Mesa. Frankly, I’m a little embarrassed that I was being too conservative; I could have easily driven faster and still made it. But I’ll debate about testing those limits later. First things first—­ah, yeah, the bathroom is down the hall on the right.

The post EXCLUSIVE: Can a 2019 Tesla Model S Make it from SF to LA on One Charge? appeared first on Motortrend.



from Motortrend http://bit.ly/2GxCAx7

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