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Articles on Electric Vehicles

June 21, 2018
Paul Gipe

Bakersfield to Ridgecrest Revisited in a Chevy Bolt


We've been exercising the legs of our Chevy Bolt EV (electric vehicle) to gain a better understanding of its behavior on long trips. This is all part of our preparation for a drive at the edge of the Bolt's range.

For my wife's birthday, I offered Nancy an all-expenses paid trip to Ridgecrest, California, including dinner at a French restaurant. Such a deal, I know. How could she refuse?

As I noted on 2015 trip in a Nissan Leaf "the trip to Ridgecrest [is] challenging because of the distance—more than 100 miles--the climb over Walker Pass, and the area’s remoteness." (See EV Trip Report: Bakersfield to Ridgecrest via Mountain Mesa.)

For EVs, the area remains remote. There are no charging stations on this route with the exception of one Tesla Supercharger. The Bolt can't use the Tesla station. There is one RV park at Mountain Mesa mid-way between Bakersfield and Ridgecrest. There's also an RV park in Ridgecrest. Both have NEMA 14-50 outlets listed on PlugShare.

We've taken the Bolt on several trips out of the San Joaquin Valley, but not the route to Ridgecrest through the Kern River Canyon and the South Fork Valley over Walker Pass.

The summit of Walker Pass (5,300 feet) is nearly 1,000 feet higher than the Tejon Pass (4,200 feet) and 1,500 feet more than the Tehachapi Pass (3,800 feet). Each 1,000 feet of elevation gain requires from 1.5 to 1.75 kWh of energy from the traction battery.

On this route, there's 2,200 feet of elevation gain from Bakersfield to Mountain Mesa, and the climb to Walker Pass from Mountain Mesa requires another 2,800 feet of elevation gain. The route then drops 3,000 feet to Ridgecrest. 

The Bolt's 60-kWh traction battery makes this route to Ridgecrest doable in one leg. And it's conceivable that you can do the entire trip on one charge as the return from Ridgecrest is largely downhill.

We chose not to chance it and took the opportunity to visit Alan Kirk and his wife Molly to pick up a few kWh as a cushion for the drive back. Kirk drives a Nissan Leaf and has his place listed on PlugShare. We charged at Kirk's home on our 2015 trip, but haven't been back since.

Though we didn't stop and charge at Mountain Mesa, we monitored our consumption as we passed by for comparison to our 2015 trip in the Leaf.

For this trip we used three estimators to calculate how much electricity we would consume on each leg: EV Trip Planner, GreenRace, and Chevy's Energy Assist app. We also knew how many kWh we used in 2015.

Here are our observations.

First, when planning such trips, it's wise to account for how many kWh you're going to use in the city you're visiting. We used 5.5 kWh just driving around Ridgecrest. While that wouldn't have exhausted the Bolt's range for the return trip, it would have left us with only 8 kWh remaining. More than enough, yes, but close enough that you would want to closely monitor your trips around town.

Second, the consumption of the Bolt on this trip was comparable to that of the Leaf. The two trips in two different vehicles differed by only 6%. Again, not a surprise--the two vehicles are quite similar. But you don't know that until you've done the route once or twice.

On the trip to Ridgecrest we used 5% of consumption for A/C. The outside temperature was in the mid to high 90s. The car used 1% for battery conditioning (cooling). The complete trip required 6% for A/C and 1% for battery conditioning.

We also found that overall Chevy's Energy Assist was the most accurate estimator. However, EV Trip Planner's Leaf α and GreenRace's 30 kW Leaf estimates were more accurate on some legs of the route. These subtleties become critical when planning a trip at the edge of the Bolt's range and suggests that drivers know the limitations of each estimator.


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