cars news 10: 2017 Chevrolet Bolt EV Long-Term Update 7: Stories From the Road Trip

I really didn’t want to get out of the car. The storm I’d been dicing with all day upped the ante from light rain to raining sideways, but there was no escaping getting wet: I’d made it to the DC fast charger and the car needed to be plugged in. Bracing myself against the wind and rain, I plugged in as quickly as possible, swiped my RFID card over the charger’s reader, and jumped back in the car. Then the whole neighborhood lost power.

I’d been simultaneously planning and putting off this trip since the day I got the Bolt. The one thing EVs struggle with—even big-battery, long-range EVs—is road trips. On the road, you’re at the mercy of the public charging infrastructure, and its quality varies wildly depending on where you’re going and even what roads you choose. Our Bolt is fitted with the optional DC fast charging hardware ($750) which Chevy advertises as being able to charge the battery “up to 90 miles in just half an hour,” but how practical is that on a real road trip? Having done this same road trip a few years ago in our long-term Tesla Model S, I knew the short answer was: not as practical as it seems.

Tesla, owning its own proprietary chargers, has strategically placed them along major freeways at a distance their cars can easily attain. The rest of us must depend on the whims of business owners who’ve decided to install fast chargers on their property. They may be nowhere near the freeway, and there are rarely more than one or two in the same place, but they’re what we’ve got to work with.

Until gas station owners start installing chargers, a long-distance road trip in an EV won’t be something you can do on a whim. Whereas I can start driving in any direction and find a gas station on the side of the freeway when I need to fill up, an EV road trip must be mapped out in advance. I prefer the app/website PlugShare, which crowd-sources charger locations, types, numbers, pricing, maintenance status, in-use status, and even charging speed. That last point is an important one, because charging speed dictates charging time and not all DC fast chargers are created equal. Older models charge at half the rate of newer machines, doubling your downtime. That’s an especially big deal when you need to stop more than once to charge on the same day of driving.

My plan was simple: with the wife out of town for work, I’d take two days and drive up to Gilroy, south of Silicon Valley, to visit friends for the night and come back. I originally planned to take the flatter, straighter I-5, but then I hit my first problem. There aren’t any DC fast charging stations with the Bolt’s SAE CCS-type plug on I-5 between Los Angeles and the Gilroy turn-off. Instead, I’d have to take longer, hillier Highway 101. Small matter. I researched my charging options on the route, calculated the mileage and charging times, and plugged the car into my home charger overnight so I’d start with a full battery. My estimated range at the outset: 211 in ideal conditions, 179 predicted based on recent driving.

After waiting out the morning rush hour, I pointed the Bolt northwest and aimed to hit San Luis Obispo, my first charging stop 190 miles away, by lunchtime. On the way, I had several decisions to make. First: speed. In a gasoline-powered car, I’d set the cruise control at 80 mph and forget about it. Speed affects EV efficiency much more than it does gasoline efficiency, however, so to be safe, I parked myself in the right lane with the cruise set at 70 mph. Going even slower would of course be even more efficient, but would also make my trip longer and I wanted to make it as similar to a gasoline-powered trip as possible. The average consumer isn’t going to accept having to drive 55 mph on road trips. I did do one thing the average consumer likely won’t: I wore a jacket and turned off the heat. Electric heaters suck up a lot of electricity and would seriously hurt my range.

The next decision was the route. At Santa Barbara, Highway 154 cuts over the Santa Ynez Mountains and cuts 10 miles off the trip. Climbing mountains uses more energy, of course, but I reasoned it was a fair trade. The speed limit is lower and I could recoup some of my spent energy on the downhill side. Plus, there’s a big hill to climb when Highway 101 crosses the mountains farther up the coast. I took the shortcut. An hour later, I breezed past my back-up charger in Pismo Beach for my primary objective 15 minutes up the road in San Luis Obispo. I covered 192 miles and had a predicted range of 36 miles left. All was going to plan.

The charger was on the edge of town and well off the freeway, but it was also in a shopping center where I could get lunch. After 45 minutes of charging, I discovered this charger had an unannounced 30-minute limit and had switched off with the battery at 70 percent. Restarting the charger of course incurred another one-time fee on top of the cost of electricity, but 30 minutes later than planned I was back on the road with an 80-percent state of charge.

This is where things started to go wrong. In my calculations, I had foolishly forgotten I’d only be fast-charging to 80 percent rather than 100. Why? Because batteries charge slower the fuller they are, and that last 20 percent can take as long as the first 80 percent. I didn’t want to spend another hour at the charger for 20 percent. My hope was to make it to Gilroy without stopping again, and per the car’s prediction, I should’ve had a 20-mile buffer. Within an hour, though, my buffer was gone and it was obvious I wouldn’t make it. I had to hit my back-up charger in Salinas. No big deal, though, as it was right off the freeway and I just needed a little extra juice to make it to Gilroy.

Then the power went out, and I had a tough choice to make. There was another charger in Salinas, on the opposite side of town and several miles the wrong direction at rush hour. The car was predicting 26 miles of range, and the Gilroy fast charger was 26 miles away. I stalled awhile, hoping the power would come back on. Reasoning I could divert to a Level 2 charger several miles out of the way in San Juan Bautista if things were looking bleak, I decided to go for it.

The rain had mostly stopped, so I killed the wipers along with the fan, headlights, and infotainment system. I took a back road out of town with a low speed limit and maximized my regenerative braking whenever I had a chance. Rejoining the highway, I parked it in the right lane at 55 mph and hoped for the best. Every mile that ticked off the range was excruciating, but they were disappearing at the same rate as the miles I was covering. Just outside of Gilroy, the range went blank and a message appeared warning me of reduced driving power as the car tried to squeeze every last electron. I made it to the charger equally elated and stressed out. Getting to Gilroy had taken me nine hours, a drive I’ve done in as little as five and a half in a gas-powered vehicle.

Already late for dinner, I didn’t spend long at the fast charger, opting to return in the morning before leaving town. I also decided against asking my friend to let me plug in my portable 120-volt charger since it only adds four miles of range per hour of charging and didn’t seem worth it. In retrospect, I should’ve just done it.

The fast charger had added 50 miles on the meter, so I figured I’d put it to good use and skipped the Gilroy charger the next morning and headed back to Salinas. This way, I’d be nearly 30 miles closer to home before I’d need to plug-in again. I put the car on the fast charger and went around the corner for a leisurely lunch, only to come back and find this charger, too, had a 30-minute limit. When it turned itself off, another Bolt owner who’d been waiting unplugged my car and started charging his. I had to wait another 20 minutes for him to finish before I could plug my car back in and finish charging.

Finally back on the road after a two-hour stop, I hoped to stretch it to Buellton 190 miles south. Knowing it wouldn’t likely happen without a full battery, I picked a back-up charger in Santa Maria, less than 160 miles away. It wasn’t long before my buffer was again gone. I simply wasn’t getting the efficiency I needed and my range was dropping like a rock. I made it as far as San Luis Obispo, to the same inconveniently located charger I’d stopped at the day before. I’d only gone 129 miles on an 80-percent charge. Theoretically, I should’ve been able to go 190 miles. At least this time I knew about the 30-minute limit on the charger.

An hour later, I was back on the road. However, having stopped 30 miles sooner than I’d planned and seeing terrible efficiency despite changing nothing from the day before, it was immediately clear I wouldn’t make it home without stopping again. Resigned to my fate, I called my brother in Santa Barbara and made plans for a late dinner while the car charged again. Unlike the last two chargers, it was at least close to the freeway. The last 95 miles home were both the most pleasant and the most exasperating. I could use the heater with abandon as I had more than enough range, but the returning feeling in my toes was tempered by the fact my return trip took 11 hours.

In total, I drove 836 miles in 20 hours. For those keeping score, that’s as much as nine hours longer than I’ve done the same trip in a gas-powered vehicle. I’d hoped to charge three times total, once each way and once in Gilroy. I charged five times, and stopped a sixth only to be denied by a power outage.

What happened? A number of things, all conspiring against me. For starters, EVs are at their least efficient at highway speeds. Doing nothing but cruising at 70 mph for hours with little to no regenerative braking put a big dent in my range. Having to take a route with more hills and turns further taxed the battery. Only fast charging to 80 percent obviously limited my maximum range. Running the wipers and headlights (along with the stereo) in the storm ate up a bit of electricity, and having to divert well off the freeway to reach chargers didn’t help. Ambient temperature outside ranged from a high of 60 degrees down to a low of 45 degrees, which while not freezing could diminish battery performance somewhat. It’s also possible I was driving into a headwind at times due to the storm. Add all those factors together and your maximum driving range on any leg of a road trip could be significantly less than the vehicle’s advertised range, just the same way towing, for example, hurts fuel economy and driving range.

Before you throw in the variables, though, there’s one inescapable truth: charging, even DC fast charging or Tesla Supercharging, takes significantly longer than filling up with gasoline, so any drive beyond your car’s range will take longer than it would with gasoline. The best you can do is plan your trip so you’ll be stopping for a meal at the same time you’ll need to charge. On top of that, it’s a compounding issue. Each charging stop adds far more time to your trip than a fuel stop. When you’ve already been on the road for hours, that matters. A lot. Add in traffic, weather, heat/AC usage, occupied or out of service chargers, unscheduled stops, and your trip could end up taking much longer than you planned.

EV technology has finally reached a point at which “range anxiety” alone is no longer a serious concern, but we’re not at the point where EVs and gasoline-powered cars are completely interchangeable. Until the gap closes, plan ahead and be prepared.

2017 Chevrolet Bolt EV Charging, Update 7
Odometer	16,451 miles
Avg distance between charges	95.5 miles
Avg pre-charging state of charge	46%
Avg range pre-charge (ideal/predicted)	112/93 miles
Avg energy per charge	28.1 kW-hr
Avg predicted charge time	6 hr, 2 min
Avg post-charging state of charge	89%
Avg range post-charge (ideal/predicted)	231/177 miles
Cost of public charging to date ($7.72/chg avg)	$362.97
Cost of office charging to date ($1.98/chg avg)	$132.83
Cost of home charging to date ($4.85/chg avg)	$131.04
Total charging cost to date	$626.84

2017 Chevrolet Bolt EV Long-Term Update 7: Stories From the Road Trip

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