Cringe. The idea had been for Ed Loh to deplete the Chevrolet Bolt EV’s battery on his return from Tehachapi, 130 miles away. Then I’d arrive in the equally dead Tesla Model S to document their refills at our garage’s chargers (where we’d added EKM meters precisely to measure things like this.) Our plan was perfect.
Except. Our route to El Segundo is seashore-tilted, and I’d been worrying that the 3,900-foot decent would make burning-off kW-hrs tougher than Ed reckoned. I climbed into the Bolt’s dark interior and pressed the start button. The display brightly blinked on—glaring, because it’s 10 p.m.. And there, in menacing digits, was my worst nightmare—80 miles remaining. I said it was 10 p.m., right? Eighty miles of range needed to be worn off before plugging it in. Hesitantly, I tapped MapQuest. The local freeways were still in a yellow knot tied by our now eternal rush-hour traffic. Expletive deleted.
A more mature take on this is to regard those yellow lines as symbolic, highlighting, if you will, just how much EV batteries have improved. In 1996, I road tested a GM EV1, and during it, we did an informal range test. The car went 55 miles, and at one point, I misgauged things and wound up with both hands on its stern, pushing it down a street. Now my problem was the opposite—too much range. What to do? I clicked on the seat warmers, cranked up the heater to full hot/max blower, and rolled the windows down to exhaust the heat and foul up the Bolt’s aerodynamics. Even turned up the sound system (can’t hurt—err, rather, hopefully it would hurt). Welcome to upside-down land.
A second reconnoiter of MapQuest showed a short, green 2-mile stretch of the 105 freeway, just north of the office. For the next 45 minutes, I ricocheted back and forth between its ends, alternating between mashing the accelerator and braking harder than the car’s regen capacity could ingest its kinetic energy.
Read the Chevrolet Bolt vs. Tesla Model S 60 comparison HERE.
Earlier, the Bolt’s technician/minder had told me that when the battery’s state-of-charge gauge illuminates yellow, it’s time to find a charger. Yellow appeared—earlier than I expected (evidence of some GM conservatism; conversely, the Model S displays remaining miles down to its very last one). I dashed another lap then headed for the office, 2.6 miles away, and glided toward its nipple of electrical nourishment. Before plugging in, though, I tortured its hunger pangs by leaving the heater blasting to develop a good appetite. After about 20 minutes—poof—the Bolt went silent. On its screen, a message desperately pleaded: “Out of Energy. Charge Vehicle Now!” Done.
The next morning, the Bolt had absorbed 68 kW-hrs of energy, the Tesla, 64.7. Is the Bolt’s charging that much less efficient? (For those of you without electrical engineering degrees, absorbing more energy is a bad thing, an indicator of inefficiency, similar to spilling gasoline at the pump, but instead it’s wasted electrons.) However, this was not the case. The Bolt’s battery is evidently larger than claimed, its usable size likely larger than its stated, 60 kW-hrs capacity (which I had run extraordinarily low; GM says a typical charge is 66.6).
To test both cars range, we decided to treat them just like we do gasoline cars and simply hand their keys to our real-world mileage-measuring partners, Emissions Analytics. True, they wouldn’t be attaching $150,000 gas analyzer to tailpipes (or be monitoring their uncommunicative OBDII ports, either). But they’d otherwise follow our tried-and-true nose-to-tail city and highway route—veteran of 400 previous tests—while documenting energy use from the display screens, repeating individual road segments to check repeatability, and then baking these disparate results in EA’s proprietary correction-analysis oven.
What we found: Our Bolt’s combined city/highway energy use of 28.6 kW-hrs/100 miles shadows the EPA’s rounded-down measurement of 28, although our observation suggests it’s actually better on the highway than the city (we got 31/26; EPA got the opposite, 26/31). Meanwhile, the 866-pound-heavier Model S returned a combined 33.3 kW-hrs/100 miles (EPA says 34). What does that mean? The Bolt threads between the original small-battery BMW i3 (the EPA’s current mpg-e champ) and the more recent enhanced-battery version of the i3 while tying the Bolt’s sibling, the 82-mile-range Spark. Except all three of those comparable vehicles can’t reach more than 100 miles on a battery charge before expiring.
Using our Bolt’s wall measurement and RMPG-efficiency, we computed a range that’s exactly 238 miles—spot on with EPA’s claim (while the Tesla crunches out at 194, short of the EPA’s 210 miles). Moreover, when we retested the Chevy in its more efficient Low mode (which the EPA hasn’t tested, or at least revealed), thanks to stronger regenerative braking, the Bolt’s energy use drops to 27.8 kW-hrs/100 miles, pointing to a range of 245 miles.
To put this in historical perspective, the Chevrolet Bolt EV achieves quadruple the range of the seminal GM EV1 while accommodating five people, not two, and being quicker to dash to 60 mph by about 1.7 seconds. All for $30,000, after incentives.
Ultimately, our guess is that most drivers are going to gravitate to moving that shift lever to Low. Not only is there the additional energy-savings cake-frosting, but the convenience of driving with just one pedal is also simply addictive.
What does one-foot driving look like? Here are five curves comparing the deceleration of the Tesla and Bolt in different modes, as I simply lifted my right foot off the accelerator (compared to the Bolt’s gliding in neutral). See how easily the Chevy could draw to a complete non-brake pedal stop? (In a few cases, I ran out of room.)
Tesla’s contention that the only successful vision can belong to an end-to-end EV maker that’s all-in—from single-purpose manufacturing to user-friendly proprietary showrooms to a bespoke fast-charging network. GM may have built a great EV with the Bolt, but only Tesla truly understands the magnitude of the mission.
The post The Chevrolet Bolt and Tesla Model S 60: Range, Charging — and Travel appeared first on Motor Trend.
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