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Discussion Starter #1
Other than the estimated EV range is there anyway to determine the remaining KWh left in the traction battery? I ask because if you don't have the chance to fully charge all the time but have partial charges you really have no idea.
 

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If you know your typical range, example in our area and my driving style, I get 64 miles for the 14.1 kWH, that's about 4.5 miles/kWh

Now divide the Guess-o-meter EV Range on the instrument panel by this number and you should get kWH remaining.
 

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Other than the estimated EV range is there anyway to determine the remaining KWh left in the traction battery? I ask because if you don't have the chance to fully charge all the time but have partial charges you really have no idea.
On the Classic Enhanced Driver Information Center display there are 10 green segments displayed on the left side of the display in an arc where each segment represent 10% of the battery state of charge. Each segment is approx. 5 miles of EV range (approx. 1.4kwh) if you assume 3.75 miles of EV range per kwh. If you regularly achieve 4.5 miles per kwh then each segment represents 6.3 miles of EV range
 

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This is a pet peeve of mine and easily correctable by GM. I see the Bolt readout has that value right on the display.


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Dashdaq
Or cell phone app with Bluetooth dongle
 

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Discussion Starter #6
Dashdaq
Or cell phone app with Bluetooth dongle
Is there a Torque configuration file for this? I have a Bluetooth dongle that works and Torque light. I'd be more than willing to spend the $5 for the full Torque if there's a Volt (gen 2) specific plug in.
 

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You could divide the Electric Miles by the kWh Used on the Energy Usage screen on the center display to calculate your ev mileage (mi/kWh) since last full charge. Then divide the estimated ev range on the DIC by the calculated ev mileage to get the estimated remaining kWh.

Range miles/ (mi/kWh) = available kWh

Not sure why knowing the estimated amount of kWh remaining is more informative than knowing the estimated ev range on the DIC. If you think the ev range estimate is too low or too high because the computer has been adjusting the on-the-fly estimated mileage to calculate the estimated range (e.g., you’ve just been driving uphill or downhill for a while) or is including a/c power use and you just turned it off, then raise/lower your ev range estimate when you do your calculation.
 

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Discussion Starter #9

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Does knowing how much gas you have left in the tank tell you whether or not you will make it to your destination? No. If you hit traffic and have to idle for an hour, you are more likely to run out of gas regardless of your mpg. If you are climbing in the rockies you will also run out of gas quicker than you might have anticipated. There is no difference with this car other than you are dealing with a different form of energy. Everything else still applies.

I've run about as close to empty as you can get in a car, and the consequences could have been dire. Having a gauge that told me we had .056 gallons of gas left would have been useless. In that case praying was much more valuable ;-)

With the Volt it might be a little bit of a game to see if you can make it somewhere on electricity alone, but it's not a gamblers game. You are betting with a huge safety net there all the time -- the ICE.
 

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If your OnStar is active, you can use the Vehicle Status in the MyChevrolet or OnStar apps on your phone.
 

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Discussion Starter #12 (Edited)
Does knowing how much gas you have left in the tank tell you whether or not you will make it to your destination? No. If you hit traffic and have to idle for an hour, you are more likely to run out of gas regardless of your mpg.
The big difference is the denominator - Miles/Gallons vs. Miles/KWh. That small KWh number in the second equation throws a lot more variability in the equation. The larger Gallons number gives you a better estimate of range. With the smaller KWh number even a tiny difference in the value can have a far greater impact on your range. Now if you're routinely in "low fuel" then neither range estimate is worth the energy needed to display it, which is why I traditionally don't allow my tank to go below a quarter in the summer and half in the winter. I know I have to reevaluate this rule of thumb in the Volt, which is part of the reason I'm asking some of these seemingly stupid questions.

If you are climbing in the rockies you will also run out of gas quicker than you might have anticipated.
Actually not true in modern ICE cars. My Cruze ECO MT got about 10-15% better fuel economy in the Rockies than on the plains with the last day trip last summer covering nearly 500 miles at 49+ MPG in mixed driving ranging from 1st gear mountain passes to 6th gear mountain passes. Modern cars implement Deceleration Fuel Cutoff that when managed properly can actually add something like 50% to your MPG in the mountains. Consider it terrain generated pulse & glide.

I've run about as close to empty as you can get in a car, and the consequences could have been dire. Having a gauge that told me we had .056 gallons of gas left would have been useless. In that case praying was much more valuable ;-)
I've done this on a handful of occasions with one situation where I believe my fuel tank was actually empty and I was driving on the 10 or so foot long fuel line from the tank to the engine. It's very nerve racking to run that low.

With the Volt it might be a little bit of a game to see if you can make it somewhere on electricity alone, but it's not a gamblers game. You are betting with a huge safety net there all the time -- the ICE.
Agreed. The Volt is still new to me and I'm trying to get as much information as I can to figure out how to take advantage of the car's features to get the most efficiency out of it. Over the years I've gotten pretty good at figuring out how much gas is left in the tank - now I'm working on figuring out how many usable electrons are left in the battery.

Also, I live in Denver and drive the west side of the city a lot. There isn't such as thing as flat ground so the closer I can estimate EV range vs. my routes the better my efficiency. I've already figured out that in a terrain generated P&G environment I need to "pulse" as an EV and "glide" as an ICE when I don't have sufficient EV to do both.
 

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I always try to keep about 200 miles of range in my Volt, electric and gasoline. While this may be considered excessive, I frequently travel to remote mountain trailheads and never want to be trapped overnight, even though I do carry three tents, two sleeping bags, two stoves, water filter, and a food supply at all times in my Volt. Probably, I am an extreme Volt user. With experience, you will know that your range on electric is conservatively about 3 miles per KwH, with a 13 KwH battery pack in the Volt Generation One.
 

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Actually not true in modern ICE cars. My Cruze ECO MT got about 10-15% better fuel economy in the Rockies than on the plains with the last day trip last summer covering nearly 500 miles at 49+ MPG in mixed driving ranging from 1st gear mountain passes to 6th gear mountain passes. Modern cars implement Deceleration Fuel Cutoff that when managed properly can actually add something like 50% to your MPG in the mountains. Consider it terrain generated pulse & glide.
You'll have a hard time convincing me of this because the physics simply doesn't support this conclusion. You can't recover everything you lose going up unless something (other than gravity) is pushing you down.

I've done this on a handful of occasions with one situation where I believe my fuel tank was actually empty and I was driving on the 10 or so foot long fuel line from the tank to the engine. It's very nerve racking to run that low.
I actually did this not far out of Denver, but far enough to be in the middle of nowhere ;-)
A little astrophysics knowledge probably saved our buts.
 

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Discussion Starter #16
You'll have a hard time convincing me of this because the physics simply doesn't support this conclusion. You can't recover everything you lose going up unless something (other than gravity) is pushing you down.
My trip report for that day is at http://www.cruzetalk.com/forum/27-fuel-economy/177089-she-likes-mountains.html.

Also take a look at http://www.metrompg.com/posts/pulse-and-glide.htm for more information on P&G driving. Driving in the mountains at a steady speed (road permitting) uses the terrain to emulate pulse & glide. To a physicist driving uphill is the same as accelerating - driving uphill adds potential energy and accelerating adds kinetic energy. Driving downhill is the glide, converting the potential energy into actual momentum. Given that my lifetime in the Cruze was 42.5 MPG and this one trip recorded 49.5 MPG. After adjusting for the 5% DIC optimism in that car this represents a 10% improvement over the lifetime average for the car.

When I made this trip I had about 80K on the odometer so I had learned to manage the engine in DFCO. This thread is actually part of my effort to jump start this same learning in the Volt. I've driven ICE cars and vans for 30+ years and know I have some serious adjustments to make to get the most efficiency out of the Volt without being a rolling road hazard.
 

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I always try to keep about 200 miles of range in my Volt, electric and gasoline. While this may be considered excessive, I frequently travel to remote mountain trailheads and never want to be trapped overnight, even though I do carry three tents, two sleeping bags, two stoves, water filter, and a food supply at all times in my Volt.
Better to be prepared...but 3 tents?! Wouldn't two suffice and more food/water be better?
 

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You'll have a hard time convincing me of this because the physics simply doesn't support this conclusion. You can't recover everything you lose going up unless something (other than gravity) is pushing you down.


I actually did this not far out of Denver, but far enough to be in the middle of nowhere ;-)
A little astrophysics knowledge probably saved our buts.
Due to the cars BSFC the above is not only probable but likely.

If ICE cars didn't have poor BSFC in the city most would get 80+mpg
As we all know that doesn't happen because the ice is oversized and inefficient at city speeds.

In the mountains you are more likely to operate at peak torque and efficiency allowing you to potentially beat flat land travel.
 

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Due to the cars BSFC the above is not only probable but likely.

If ICE cars didn't have poor BSFC in the city most would get 80+mpg
As we all know that doesn't happen because the ice is oversized and inefficient at city speeds.

In the mountains you are more likely to operate at peak torque and efficiency allowing you to potentially beat flat land travel.
Still not buying it. The OP reference talked a lot about empirical mpg calculations, but nothing about the actual physics. Just because you can coast down a mountain for 0 energy does not mean you more than double you mileage for the up portion compared to if it were flat. You could just as easily operate your engine at peak torque on a flat straight away.

I will fall on my sword if someone can provide a "proof" otherwise.
 

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Discussion Starter #20
Better to be prepared...but 3 tents?! Wouldn't two suffice and more food/water be better?
It's Colorado. I'm guessing one tent is a heavy duty four season tent, one is a lightweight 3 season tent, and the third is a large "family" style tent. I don't know Copprsnowboarder but I think three tents is on the low side - I have eight tents. I also have two backpacks - one for weekend trips and one for week or longer expeditions.
 
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