A 750 mile road trip in the Solterra EV

This trip took a lot more than I thought it would... I got started a little later than I had originally planned, leaving West LA around 11:20 a.m., with a 98% state of charge (SOC) and 197 miles estimated range [with 3,821 on the odometer].

The plan for the trip, worked up using PlugShare, was to drive 126 miles to Rancho Mirage Marketplace, DCFC to 80% there, drive another 130 miles to Love’s Travel Stop Quartzsite, another charge to 80%, another 111 miles to Palm Valley Crossing in Goodyear, and then I’d be about 10 miles from my destination.

Apple Maps was saying it was a 5 hour, 34 minute trip there (nonstop direct), and I figured, recharging to 80% twice en route would add a bit more than an hour to that trip time. After all, Subaru claims the 2024 Solterra’s “high-capacity lithium-ion battery charges from 10% to 80% as quickly as 35 minutes.” 🤣 ... 😡

By 1:20 p.m. I had made decent time, averaging 2.9 m/kWh with a fair amount of climbing (about 2500'), and using the cruise control to stay between 75-79 mph to keep up with traffic. I stopped at the Rancho Mirage Marketplace [3,944 (123 miles traveled)] for the EVgo charging station, which has a PlugShare of 10 and shares a parking lot with a nice Gelson’s market. It took a minute or so to find the chargers, and then one of them just didn’t work at all (an issue reported by other reviewers), but once I found a working station, it charged reasonably quickly. I ran into the market and grabbed some sushi for lunch. I parked at 30% SOC and an estimated 60 miles of range remaining. Charged to 80%, which took 36 minutes delivering 33.4516 kWh at $.68/kWh (!!) plus a “session fee” of $2.99 ($25.77 total), and gave me an estimated range of 156 miles.

There was an accident and construction on the 10, so I sat motionless for ... too long. Elevation changes, too, from ~400' above sea level up to 1,672', then back down to about 400', then back up to about 1,250', then down to about 900'. I got to the Love’s Travel Stop Quartzsite [4,073 (129)] about 6:15 p.m. local time (6 hours after starting the trip), with 0% SOC and “---” miles estimated range. The last hour or so of the trip I ran cruise at 59 mph and stuck to the right lane. Too close for comfort!

Cutting it close!

According to the ElectrifyAmerica charger, I was initially charging around 100 kW, and the report at the end says I started at 1% (the car was displaying 0% and had been for a couple of miles at that point). A few data points:

Charging Time  SOC  Charge Speed  Energy Delivered  Note
3 min           8%  100 kW         5.2960 kWh
12 min         31%  103 kW        19.9200 kWh
27 min         64%   65 kW        41.5280 kWh       40 min to 100%
43 min         84%   36 kW        54.9360 kWh       25 min to 100% 

(So the car seems to be reporting ~66 kWh to the EV charger as 100% capacity ... Though if you figure maybe 10% energy loss through the charging process? ... then you’re back up to the spec’d ~72 kWh battery.) 

The final report showed 43 minutes of charging time to go from 1% to 84%, transferring 54.9840 kWh. That was enough to get me to my destination in Glendale, Arizona (123 miles), and then another 11 miles to a charging station (Palm Valley Crossing), with some margin of error not not a huge one. While it was charging I ran into the Love’s and got a sandwich from Subway. It’s been a long time since I’ve popped into a travel stop...

The terrain was more favorable for this next leg, though it started with a relatively steep climb from ~900' MSL to about 1,700' MSL, back down to about 1000' elevation, climbing back up to about 1,300', then almost entirely downhill into the Phoenix area. I averaged about 2.5 m/kWh at 80 mph. Got where I was going [4,192 (119)] about 8:34 p.m., 8.5 hours after I started the 5.6 hour (supposedly) trip. I had 19 miles estimated range remaining, at 10% SOC.

Ten miles later (10:04 p.m.), at that Palm Valley Crossing stop [4,202 (10)], I had 10 miles estimated range and 5% SOC. My planning is getting better, but could still use some tweaking. At that EVgo station, the car was slurping power at 65 kW, jumping from 5% to 21% in about 13 minutes and estimated about 75 more minutes to get to a full charge. I was done stretching the charge, and decided to just go to 100% vs. stopping at 80%, as there were several open stations and no one waiting. Popped into a gas station convenience store to get some Mountain Dew and snacks.

At 11:40 p.m. local time, I was ready to get on the road again, with 100% SOC and 182 miles estimated range. (I somehow neglected to note the amount of energy transferred, but I’m guesstimating going from 5% SOC to 100% SOC took about 62.7 kWh, based on my other charging this trip.)

Homeward bound

I got to my next charging spot, Wiley’s Well Rest Area [4,350 (148)], just before 1 a.m. local time, about 14 hours after I started this trip. This was a bit of a gamble, as there’s only one charger, a 62.5 kW station, but it’s free (provided by CALTRANS), and since I was at 100% SOC starting this leg, I had some flexibility if I needed it. Fortunately, no one else was using it, and I hooked up with 19 miles remaining and 10% SOC. The car reported 1 hour 5 minutes to 80%, 1 hour 50 minutes to full charge. I decided to go for a full charge again, and recharged myself a bit while I waited. Outside temp was 55°F, and it was windy, but in the car with a light covering I was more than comfortable, and settled in for a nap.

Exactly one hour later, the car was at 140 miles estimated range and 80% SOC, with 30 minutes remaining until fully charged. 31 minutes later, it was up to 160 miles range and 92% SOC, and 26 minutes after that, it automatically stopped charging, as it was full, 56.9712 kWh transferred. Local time now 2:52 a.m., about 16 hours after I’d started. I left Wiley’s Well Rest Area with 177 miles estimated range, 100% SOC. My next stop would be a Walmart Supercenter with charging stations, about 151 miles away. GPS said it would be a 2 hour 17 minute trip).

13 minutes later [4,363 (13)] I was in Desert Center, down to 93% SOC and 164 miles estimated range. Sigh.

An hour after that [4,429 (66)] I was in Coachella, at 63% SOC with 111 miles range, having averaged 2.8 m/kWh at 70 mph.

At 5:22 a.m. local time I was in Colton [4,499 (70)]. I’d averaged 3.0 m/kW and arrived there with 35 miles of range and 20% SOC. Home was about 65 miles away, which was predicted to take another 1 hour 24 minutes.

It took me 19 minutes to charge to 50% SOC (20.7520 kWh delivered), at $.64/kWh ($13.24). I departed at 5:42 a.m. with 88 miles estimated range.

Got home just before 8 a.m., almost 21 hours after I left home.

Finally got to my charger at the office [4,568 (69)] with 25% SOC and 45 miles estimated range, having run the heat a couple of times on the final leg.

Charging costs were on the high side (except the free one) and kind of all over the place, so I’m not going to crunch those numbers. Also, there were enough abnormal conditions (dense urban rush hour at the end of the trip; that hour or so spent literally sitting in traffic mid-day) that I can’t really calculate how much time I spent “driving,” so I won’t. But my take-aways:

Total distance traveled: 747 miles. Energy consumed: Roughly 229 kWh (about 2.73 m/kWh if you don’t include the first 123 miles, which I don’t have kWh numbers for, since I started with a 98% SOC). Because the Level 3 DCFC chargers I used varied a bit in their capability (from the ~62 kW freebie to the high speed chargers that could deliver, at least for a while, ~100 kW to the Solterra), I don’t have a great set of numbers to calculate real-world charging performance. But based on my limited sample, I can say a good high speed charger will take somewhere between 5-7 minutes, roughly, for every 10% of charge added up to 80%. (I spent about 5.2 hours (!) attached to L3 chargers on this trip. The first leg, )

Some nail biting moments, and range fell short of what was estimated. Kinda like these guys (year old video, but the Solterra hasn’t changed much vis-a-vis range):

Anyway. I don’t road trip that often, but I’ll definitely have to keep these lessons in mind if I want to hit, say, Mammoth. Using the first leg as a guide, charging on beefy L3 chargers to ~80% SOC, with a fair amount of hill climbing and all higher freeway speeds, I went 381 miles starting with a full charge and spent 79 minutes (about 1 hour 20 minutes; average ~40 minutes per stop, assuming the chargers aren’t occupied and they work and ...) charging en route, so, I should plan to stop every ~125 miles and time budget 45 minutes per stop, if I pick good stations with a lot of availability. On trips with better charging station density, it definitely seems like it will make more sense to limit charging to 80%, too, as it was significantly slower charging that last 20% (which I knew would be the case).

Let’s see how those estimates match reality over the next 5,000 miles! I have a mini road trip planned for tomorrow...