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A question about the use of the low gear setting. I just took a 110 mile trip, mostly highway -- 60-70 mph with air conditioner on. First 50 miles was on electricity. Second 60 was on gas.

I use Low for all my driving around town, and I use the regen paddle as much as possible. So I did the same thing on the highway, including when I was running on gas.

Total MPGe for the trip was about 50, which seems low to me. I didn't check the energy info screen at the point that the battery ran out, but freeway MPGe for me on electricity is typically something like 100 or 110. If I got 110 MPGe for half of that trip, I must have been getting more like 30 or 35 on gas, which seems low to me.

Was a I making a mistake to keep it in low gear? Anything else I should have done? And what kind of mileage are you all getting on gas alone?

Thanks to anybody who has any thoughts about this --

Steve
 

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Shouldn't make any difference although what you lose in momentum when off the gas you do not make up for in regen so in that sense D would be better. Did you use CC? Traffic heavy necessitating slowing down and speeding up. Hilly/mountainous?
 

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AC on for the whole trip. Moderate traffic so not much speed variation. Mostly flat terrain.

I think another way to make your point is that on the freeway, when you let your foot off the gas, you'd get more efficiency by allowing the car to coast?

S
 

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For a Gen 2 Volt 50 miles of EV range @ 65-70 MPH average seems right. To get 60 miles or more of EV range try keeping your speed to a maximum of 55-60 MPH. MPG on gas at any speed up to 70 MPH should meet or exceed the EPA rating of 42 MPG average. Driving in L or D would not make much difference. Were you using Cruise or Adaptive Cruise?

The biggest factors affecting MPG/MPGe are your speed, terrain, driving conditions (was it raining?), climate control (AC can typically use ~6-8% of your battery) load you were carrying, type of tires and tire pressure, cleanliness of the exterior of the vehicle.
 

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D would have been a little more efficient because it allows for longer coasts (you can let off the throttle earlier, thus saving the power needed to maintain speed). On level ground at the speeds you were driving you should have seen 40-45 MPG on gas, but that assumes you aren't throwing away power by staying on the gas too long. L forces you to stay on the gas longer. I would have expected 55 to 60 miles on electric as well, which you appear to have received.

Best fuel efficiency in the Gen 2 Volt requires the same techniques as best fuel efficiency in a modern pure ICE car. By this I mean moderate accelerations, let off the throttle early, and don't follow too closely which forces you to use your brakes more. Yes, the Volt's brakes aren't used much but you will always consume more energy to slow down and then accelerate again. I know a lot of Volt owners stay in L all the time but D will allow you to coast more and therefore not use as much energy maintaining a constant speed.

For the air conditioner I've discovered I can use Eco by dropping the temperature a couple of degrees from where I want it. This requires less energy to the blower, which consumes significantly more energy than the extra load on the A/C compressor by dropping the temperature. Also, use Auto on the temperature as the car will then use the recirc ducting to start with cooler air when it's chilling the air, again using less energy.
 

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A question about the use of the low gear setting. I just took a 110 mile trip, mostly highway -- 60-70 mph with air conditioner on. First 50 miles was on electricity. Second 60 was on gas.

I use Low for all my driving around town, and I use the regen paddle as much as possible. So I did the same thing on the highway, including when I was running on gas.

Total MPGe for the trip was about 50, which seems low to me. I didn't check the energy info screen at the point that the battery ran out, but freeway MPGe for me on electricity is typically something like 100 or 110. If I got 110 MPGe for half of that trip, I must have been getting more like 30 or 35 on gas, which seems low to me.

Was a I making a mistake to keep it in low gear? Anything else I should have done? And what kind of mileage are you all getting on gas alone?

Thanks to anybody who has any thoughts about this --

Steve
L is probably just a tad less efficient than D on the highway, but I like it to keep my speed rocksteady. If you drove 50 miles on electric, that would imply a MPGe of about 100. To average 50 makes no sense at all, as your gas MPGe must have been ridiculously low. Are you sure you weren't driving into a huge headwind? Towing a tank? Dragging a brake pad?

The only thing that makes sense to me is that perhaps you didn't drive 50 miles on electric, but something less like 40 miles. That would be closer to 80MPGe. Then doing the remainder on gas at about 33mpg, would give you something closer to 50MPGe.
 

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Where is the FUN in D MODE :)

I would say that most times I take my foot off the the (GAS) or stop holding it down I want to slow down or stop.

NOW we need a safety study on reaction time of people and L vers D.
 

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There's a reason they call it "L" ... for "Low". L works best for conditions that require the maintenance of a lower speed, like going down steep hills. Otherwise the car is much more efficient driving in D. You could probably get close to the same efficiency on the highway using L, but you'd have to be extra vigilant about your surroundings, and be able to hold your foot very steady.
 

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Most of the time when I am driving on the highway I use the ACC. I prefer to drive in D on the highway but sometimes I forget and drive using L. I've never noticed any difference in EV or gas range when using D or L but my highway trips are always under 40 miles.
 

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When I got my first Volt, there was still a bit of "ICE gear" mentality -- that somehow driving at high speeds in a "LOW" gear would be "bad" for the engine. But it's just not a cause for concern with an electric motor. It is purely personal preference.

Personally, I like that LOW offers more control over the driving experience at all speeds, including highway. Where I live, it's not unusual to suddenly "slow down" on the highway thanks to mammoth traffic.

But as others have said, LOW will definitely hold your speed more tight while D will let you drift downhill. Likely slightly more efficient, but when you get the hang of LOW you'll be able to learn how to "coast" in L similar to D with a feather touch to the pedal.
 

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A question about the use of the low gear setting. I just took a 110 mile trip, mostly highway -- 60-70 mph with air conditioner on. First 50 miles was on electricity. Second 60 was on gas.

I use Low for all my driving around town, and I use the regen paddle as much as possible. So I did the same thing on the highway, including when I was running on gas.

Total MPGe for the trip was about 50, which seems low to me. I didn't check the energy info screen at the point that the battery ran out, but freeway MPGe for me on electricity is typically something like 100 or 110. If I got 110 MPGe for half of that trip, I must have been getting more like 30 or 35 on gas, which seems low to me.

Was a I making a mistake to keep it in low gear? Anything else I should have done? And what kind of mileage are you all getting on gas alone?

Thanks to anybody who has any thoughts about this --

Steve
I had the same question for other volt drivers in some other posts. MY2018 has about 40 MPGcs, and I can't seem to get it close to 50 (like some other folks in this forum). But I looked at voltstats and how other 2018 models are getting; they are also reporting mpgcs of around 38-40 (except the top two). At least it's good to know my car is just like many other cars out there in that department (based on that small sample). You can sort it by mpgcs here and see it yourself.
https://www.voltstats.net/Stats/GroupDetails/341
 

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I had the same question for other volt drivers in some other posts. MY2018 has about 40 MPGcs, and I can't seem to get it close to 50 (like some other folks in this forum). But I looked at voltstats and how other 2018 models are getting; they are also reporting mpgcs of around 38-40 (except the top two). At least it's good to know my car is just like many other cars out there in that department (based on that small sample). You can sort it by mpgcs here and see it yourself.
https://www.voltstats.net/Stats/GroupDetails/341
Are you guys running on gas on highway only with constant speed? I get 48-52 mpg consistently running ICE only at 68-70mph, 50-80F. Never seen mpg below 40. I am at 11k miles. Short running of ICE (due engine warm-up losses) and lower speeds lower mpg. Lowest I saw was probably 42 with couples miles of ICE.
 

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I get 48-52 mpg consistently running ICE only at 68-70mph, 50-80F. Never seen mpg below 40.
What's your "terrain score?" In my area, there are lots of little hills (overpasses, etc.) and that definitely takes its toll on my MPG. I'm always at -2.5 without fail.

Flat roads, even at higher speeds, I get better MPG. Also, the Gen 2 is definitely much more sensitive to temperature and terrain. I saw a big jump when it warmed up.
 

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I had the same question for other volt drivers in some other posts. MY2018 has about 40 MPGcs, and I can't seem to get it close to 50 (like some other folks in this forum). But I looked at voltstats and how other 2018 models are getting; they are also reporting mpgcs of around 38-40 (except the top two). At least it's good to know my car is just like many other cars out there in that department (based on that small sample). You can sort it by mpgcs here and see it yourself.
https://www.voltstats.net/Stats/GroupDetails/341
The real trick to maintaining good MPGcs numbers is never use the ICE unless you're going 300 miles. That's basically impossible, but the goal is this: warming up the engine wastes about a soda-can of gasoline every time it happens. Avoid doing that. If you've got a trip where your choice is "hold mode on highway twice" or "run out of charge on the way back", then run out of charge on the way back. Even the stop/start cycling of city driving is more efficient than heating the engine from cold twice.

After managing engine heating cycles, slowing down gets you better efficiency. 70 is better than 80. 60 is better than 70. For Gen 1, the sweet spot for ICE-on travel is about 50-55 MPH. (ICE-off peak efficiency is about 23-24 MPH.) That keeps the ICE running almost all the time, but at its lowest production rate. Below that and it cycles off enough that you lose some economy with the heating again and the engine may start revving up a little bit to make that heating happen faster. Even if you go through a little town with a stop sign every ten miles, the gains from travelling at 60 instead of 75+ will FAR exceed the loss from the stop.


I'm sure I'll get a bunch of people arguing with me over this, but all I can say is "I can keep VoltStats monthly MPGcs at 44+ for half the year in Wisconsin, and push close to 50 for three months of those, in a Gen 1". And that's by month, not just a one-off trip, downhill and down wind.

And on the subject of VoltStats, look mostly at the months. The little summary box seems to average MPG figures by months, not miles/gallons overall. Which makes a cold month with a gallon of ERDTT burning weight just as much as the month that you burned 10 gallons efficiently, and brings the "total average" down further than it should be.
 

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L holds speed better in cruise control on downhill runs. If the road is mostly flat where excessive speed downhill wasn't an issue, D would be slightly more efficient.
 

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The real trick to maintaining good MPGcs numbers is never use the ICE unless you're going 300 miles. That's basically impossible, but the goal is this: warming up the engine wastes about a soda-can of gasoline every time it happens. Avoid doing that. If you've got a trip where your choice is "hold mode on highway twice" or "run out of charge on the way back", then run out of charge on the way back. Even the stop/start cycling of city driving is more efficient than heating the engine from cold twice.

After managing engine heating cycles, slowing down gets you better efficiency. 70 is better than 80. 60 is better than 70. For Gen 1, the sweet spot for ICE-on travel is about 50-55 MPH. (ICE-off peak efficiency is about 23-24 MPH.) That keeps the ICE running almost all the time, but at its lowest production rate. Below that and it cycles off enough that you lose some economy with the heating again and the engine may start revving up a little bit to make that heating happen faster. Even if you go through a little town with a stop sign every ten miles, the gains from travelling at 60 instead of 75+ will FAR exceed the loss from the stop.


I'm sure I'll get a bunch of people arguing with me over this, but all I can say is "I can keep VoltStats monthly MPGcs at 44+ for half the year in Wisconsin, and push close to 50 for three months of those, in a Gen 1". And that's by month, not just a one-off trip, downhill and down wind.

And on the subject of VoltStats, look mostly at the months. The little summary box seems to average MPG figures by months, not miles/gallons overall. Which makes a cold month with a gallon of ERDTT burning weight just as much as the month that you burned 10 gallons efficiently, and brings the "total average" down further than it should be.
Ok, I am clear on your 2nd point to go with slower speed.

Back to the first point though. Say I have 500+ miles trip. I want to reserve battery for the city driving. So when I get onto highway, I switch to hold mode. Drive till I reach the local roads. Then I switch to normal mode. Do the same thing on the way back. When I reach home, I have about 5-10 EV miles left.

For this scenario, are you saying switching back/forth between hold and normal mode wastes more energy than purely setting it Hold mode once (for each trip)? I am a bit confused about "warming up the engine wastes energy" because where I am right now is summer and there is no "intentional" warming up happening as far as I know. And I've been driving the car for about 3 months now (from June till now). And the temp has been quite high (75+ F).
 

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What's your "terrain score?" In my area, there are lots of little hills (overpasses, etc.) and that definitely takes its toll on my MPG. I'm always at -2.5 without fail.

Flat roads, even at higher speeds, I get better MPG. Also, the Gen 2 is definitely much more sensitive to temperature and terrain. I saw a big jump when it warmed up.
My driving area (SoCal) is definitely not hilly. My terrain score should be around +3/5.

hellsop makes a good point about double warming up the engine when it is avoidable. Heating up the engine twice unnecessarily will waste more energy (lower mpg). Something that I try to avoid. A soda-can of gasoline wasted to warm-up the engine is a little excessive though. Maybe 1/5 of that.
 

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Ok, I am clear on your 2nd point to go with slower speed.

Back to the first point though. Say I have 500+ miles trip. I want to reserve battery for the city driving. So when I get onto highway, I switch to hold mode. Drive till I reach the local roads. Then I switch to normal mode. Do the same thing on the way back. When I reach home, I have about 5-10 EV miles left.

For this scenario, are you saying switching back/forth between hold and normal mode wastes more energy than purely setting it Hold mode once (for each trip)? I am a bit confused about "warming up the engine wastes energy" because where I am right now is summer and there is no "intentional" warming up happening as far as I know. And I've been driving the car for about 3 months now (from June till now). And the temp has been quite high (75+ F).
In this scenario I would use Normal all the way home. Having anything left in your battery when you get home is wasting gas. Electric is close to three times as efficient.
 

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It does cost a few cents more to keep ~3-5 miles of EV range left in the battery when you arrive at your destination or back home. I prefer to let the ICE cool off (see what I did there) for the last part of my drive time before parking my Volt in my garage, especially in summer. My garage can reach near 100F during the day, I see no benefit to parking a car with a hot engine (~190F) inside the garage.
 

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It does cost a few cents more to keep ~3-5 miles of EV range left in the battery when you arrive at your destination or back home. I prefer to let the ICE cool off (see what I did there) for the last part of my drive time before parking my Volt in my garage, especially in summer. My garage can reach near 100F during the day, I see no benefit to parking a car with a hot engine (~190F) inside the garage.
There may be some small benefit of doing this, but it takes several hours for a hot engine to cool down.
 
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