First, let me state unequivocally that we love our Chevy Bolt. As I've mentioned in previous posts in my EV Category, the Bolt has become our primary vehicle. Unlike many EV owners and most Internal Combustion Engine (ICE) car owners, we have no concerns about taking our EV on longer trips. Last summer, we drove from California to Oregon and back for the eclipse (over 1200 miles), and we regularly do trips of 350 or more miles in a day. But I'm getting a bit ahead of myself.
We chose the Bolt because for us, it was the most practical EV available. In addition to not wanting to pay nearly 6 figures for a Tesla, we needed a car that could carry bikes, surfboards, kayaks, stand-up paddle boards, and more. I also needed to be able to park it in remote places without fear of someone vandalizing an expensive car. The Bolt has served us well.
In fact, we are continually amazed by what we can do in the Bolt and its impressive range in a variety of road conditions. On our trip to Oregon for the eclipse, driving at 75-80 miles per hour for most of it, we averaged nearly 3.9 miles per kilowatt hour (kWh). That's 238 miles of range at highway speeds even with the AC set to 70 degrees and hundred-degree temperatures in the Sacramento Valley.
Those longer trips I mentioned? At least twice a month, we make a trip to our place in the Sierra Nevada, mostly at 70+ mph, and amazingly, we average at least 4 mi/kWh. This is with two adults, a full-sized spare tire, jack, etc., and sports toys. And again, we run the AC through the heat of the Central Valley. We see similar results on our trips to the North Bay (100 miles each way). So what am I complaining about?
Well, there is one other trip that we do at least once a month. We drive from Santa Cruz, California to San Luis Obispo, California. It's about 175 miles each way and we do it in a day, charging a bit over an hour at an EVgo station in San Luis during our meeting there. There is a sizable hill (1500 feet) just outside of San Luis, but the net altitude difference between Santa Cruz and San Luis is less than 300 feet (Santa Cruz is at sea level).
Even in winter, it's a stretch to get near 4 mi/kWh. We come close, but I attribute the lower range to the road surface which is largely concrete and isn't in the best of shape. Still, we have no concerns whatsoever making this round trip with just a charge in San Luis.
Our real problem strikes in the late spring and summer. Getting down to San Luis isn't a problem but the return is sometime touch and go, even though it's mostly downhill. So what's the problem?
In the late spring and summer, the ocean is cool and the land is warm. Often it can be in the low 60s in Santa Cruz, and well over 100 just a few miles inland. This temperature difference creates wind. Worse for us, the Salinas Valley, through which we have to travel for this trip, has mountains on each side, creating a wind tunnel/venturi effect. We're often facing 40+ mph headwinds on our return.
A lot has been written about how speed affects the range of EVs, and gas mileage for ICE cars: the aerodynamic resistance increases by the square of the velocity. And while the Bolt has a somewhat respectable coefficient of drag (Cd) at about .31, when we try to drive 65 mph against a 40 mph headwind, our efficiency drops to 2 - 2.5 mi/kWh. With a 60 kWh battery, that means our range drops to between 120 and 150 miles.
So, while we were confident that with our Bolt purchase (actually a lease), range anxiety was a thing of the past, for this trip, it's back.
Our return this past Wednesday was rough. We lucked out after climbing the 1500' Cuesta Grade where we first encountered the wind and saw our efficiency drop to 2.5 mi/kWh (even slightly downhill). Ahead of us was an mCoach and it was driving 65 mph. I pulled in behind, and our mi/kWh went up to 4.5! We followed it for about 40 miles, but the driver got annoyed (sorry about that!) and forced me to pass him by pulling in front of a truck and slowing down, leaving me no room to pull in behind. I passed and slowed to 60 mph, but we were still down to 2 mi/kWh against a crazy headwind.
At King City, the half-way point, we decided to stop to charge at the Chargepoint there to provide a comfortable buffer. But as often seems to happen with Chargepoint level 3 stations, it was down. I called and they opened a ticket.
We nervously pulled back onto 101 for the worst of the wind. Dust storms surrounded us from King City to Salinas. Again, we lucked out. I pulled in behind a large semi, and followed at a sedate 55-60 mph. Ultimately, we made it home in the orange with very little left on the battery, and less than 20 miles on the GOM.
So, after a year and a half driving the Bolt, I can honestly say that our only real disappointment is its performance against a headwind. To some degree, I find it hard to believe that it has a Cd of less than .31; a headwind severely impacts range.
And while I'd certainly like to see a Nav system on the Bolt since we often drive where there is no cell service, if GM is listening, it would be very nice to see an improvement in Cd. Not only would it help out in situations like ours, I'm sure it would significantly increase the already remarkable range of the Chevy Bolt.
Since the Bolt is already strong on tech and has surround cameras in the Premier model, maybe GM could remove the side-view mirrors like Audi is doing in the European version of their eTron Quattro which ships in the fall.