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Mountain Mode not needed (Gen 2)

6065 Views 25 Replies 11 Participants Last post by  wordptom
It's leaf peeping season in Colorado, so this morning I filled my tank and headed for the mountains. I live at 5,700 ft above sea level and ran out of battery after a little over 47 miles and a net climb of 2,800 ft. I stayed in Normal mode the entire loop, driving over Kenosha Pass at 10,000 ft, Independence Pass at 12,095 ft, Vail Pass at 10,662 ft, and through the eastbound bore of the Eisenhower tunnel at 11,158 ft. I drove the posted speed limit the entire way and kept my Volt in Normal mode the entire time. Kenosha, Vail, and Eisenhower approaches are posted 65 MPH. Kenosha isn't that steep so my car was only pulling about 20 KW on the climb. Climbing Vail and Eisenhower my car was running about 40-45 KW power output and the ICE was happily screaming along. I was even able to accelerate up both passes to about 80 MPH using the Normal mode "low" buffer in the battery. The descent from Independence Pass to Aspen actually resulted in three bars of power being regenerated. When I got to down to Georgetown I got off I-70 for a bathroom break and had one bar of battery from the descent. My car correctly identified it as "gas" power and allocated it to the gas fuel economy number even after I restarted the engine even though the Classic Enhanced display showed battery power only upon restart.

Here's the Energy Usage display when I got home.
Electronics Multimedia Technology Electronic device Gps navigation device

The leaves were stunning with a variety of greens, yellows, and reds throughout the drive.

One other note: I was passed on I-70 by a CDOT (Colorado Department of Transportation) painted Chevy Bolt. Interesting...
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Did you drive in D or L for the ascents and descents?
The big issue with this theory is the posted speed limits on roads like this tend to be 35 MPH or lower. I've seen some in Colorado where the switchbacks are so frequent and sharp the posted (white sign) speed limit is 15 MPH. On the other hand, the Volt is definitely not the car I'd want to enter in the Pikes Peak Hill Climb simply because you do have a lot of slow hard turns followed by hard acceleration. The Naturally Aspirated ICE in the Volt simply wouldn't have enough power to maintain the battery SOC and the battery is probably too small for this type of driving. On these two climbs there was enough battery SOC to accelerate from 50 to 70 MPH going up Vail Pass after passing a car that had just passed a semi and the from 50 to 80 MPH going up to the Eisenhower Tunnel after to get out of a three lane jam of slow cars. In both cases I resumed the cruise control and let my car slow back down - the Colorado State Police actually monitor the three lane climb to the Eisenhower Tunnel for aggressive driving and I actually did see someone pulled over about two thirds of the way up to the Tunnels.

I had a similar thought driving across the high desert valley between the east end of Glenwood Canyon (6,000 ft) and Avon (7,400 ft) at the posted 75 MPH. In fact, based on prior experience in Kansas at 75 MPH where Mountain Mode was 100% depleted I wasn't sure the car would maintain the "empty" SOC in preparation for the actual Vail Pass climb that starts only a few miles east of Avon (Avon is west of Vail). Battery's SOC for "empty" was apparently maintained and I had sufficient battery power on both approaches to accelerate between 20 and 30 MPH. The battery portion of the power meter reached 100KW on both those accelerations.

Based on the power differences I've seen when I'm alone in my Volt vs. when my wife and I are travelling together with a fully load cargo area/back seat I suspect the ICE is still powerful enough by itself to not require Mountain Mode. Remember, the Volt's ICE is Naturally Aspirated (NA) and I took the car up the steep approaches to the two highest points on the US interstate system at 65 MPH and it didn't miss a beat. The ICE screamed but didn't miss a beat and wasn't maxed out on the power meter

Unless there is sufficient battery SOC to provide additional power the Gen 2 Volt is capable of generating up to 48kW output via motor generator A (MGA) when the ICE is running.
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