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Greetings, Volters! I'm on the verge of buying a 2017 Volt - hopefully this coming Monday :D

I was thinking about the MPG rating of the gas engine, which I believe is 42 mpg. As an owner of Prius and Civic hybrids, I became adept at stretching the mileage ratings of those vehicles by 10% or more.

So, I was wondering if I could do the same with the Volt, but I don't think it's possible. Since the gas engine is basically an electricity generator, isn't it true that my driving skills wouldn't have an impact on the MPG? In other words, no matter how fast or slow I drive the gas engine will still spin at the same rate and use the same amount of gas while it's generating more electricity?

Or, does it slow down (or even stop) once the battery reaches a certain level of charge, and then if I drive judiciously and maximize the use of the battery it would delay a restart of the gas motor - thus improving the MPG?
 

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The same techniques which get good MPG in a Prius or any other car will do the same in the Volt. The one extra trick is that, since the efficiency when running on battery in city driving is relatively better, you can maximize range and efficiency by using the battery more in slower traffic. But in practice most people use the gas generator infrequently enough that it maximizing MPG when running the generator isn't that important in the overall scheme of things.
 

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The higher the charge of the battery, the less your engine will need to run, just like in the Prius and other HSD vehicles. The only difference is that the Volt can run the engine at its optimum RPM for the power needed regardless of speed. If you accelerate fast, your battery will drain faster and it'll need to run the engine at a higher power to accommodate for the quick drop in charge, but if you accelerate slower and use aggressive regenerative braking, the engine will be used less during acceleration and can turn off sooner during coasting.

I have noticed that the Volt's engine is much more hesitant to turn off while moving than Toyota's HSD engines. HSD-powered vehicles will stop the engine almost as soon as you coast while under ~40 MPH, whereas the Volt likes to keep it running until you've been coasting for a good 10 seconds, but you can still definitely use your driving techniques from the Prius in the Volt. I managed to get my range-extending-only MPG up to around 46 by driving like I did in my old Highlander Hybrid.
 

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Greetings, Volters! I'm on the verge of buying a 2017 Volt - hopefully this coming Monday :D

I was thinking about the MPG rating of the gas engine, which I believe is 42 mpg. As an owner of Prius and Civic hybrids, I became adept at stretching the mileage ratings of those vehicles by 10% or more.

So, I was wondering if I could do the same with the Volt, but I don't think it's possible. Since the gas engine is basically an electricity generator, isn't it true that my driving skills wouldn't have an impact on the MPG? In other words, no matter how fast or slow I drive the gas engine will still spin at the same rate and use the same amount of gas while it's generating more electricity?

Or, does it slow down (or even stop) once the battery reaches a certain level of charge, and then if I drive judiciously and maximize the use of the battery it would delay a restart of the gas motor - thus improving the MPG?
I have a 2012 Volt. It isn't uncommon at all to get 42 MPG in it on long trips. I would think I could probably get 46-50 in a new Volt, not counting the electric only range. Driving technique is important in all cars. Technique, Terrain, and Temperature all play a role even with the Volt. The Volt has a sweet spot between 40 and 60 mph. The faster you go the less MPG just like any normal car. The Volt really shines on rural roads and you can get extremely impressive MPG (way beyond what the EPA estimates). The Volt is much more consistent on the highway, but I generally get spot on 40MPG on the highway traveling at 70mph and I usually average 42MPG or above on rural roads. We go on many long trips as a family so I can probably give a little better estimate than most. My numbers here are totally ignoring the initial electric range.
 

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I'm currently averaging 49 MPGcs and recently it has been well into the 50s at interstate speeds (78 to 80 MPH on average). This number is not really representative as I've been gaming the system to reset the hold point to avoid regenerating extra battery power at highway speeds (forced regen was a huge efficiency killer in my other hybrids). The number is not representative of pure CS mileage because I'm trading some grid electricity to inflate up my CS, but it appears to be more efficient than just using Normal to deplete the battery and Hold otherwise, even when Normal is strategically used in lower speed areas.

I have a routine 120 mile trip that I can use as a reference, but I don't have enough of a sample size to say for sure.

To answer the OP's question, I don't think the Volt's CS milage is set in stone and some technique can improve it.
 

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Your driving style will affect mpg when using the gas engine, even though it is only generating electricity. Drive in hold mode and watch the mileage display on one of the trip odometers, You will see the mileage go down while going up a hill, and it goes up as you let off on the accelerator pedal while coasting or going downhill.

The thing is though, with a Volt the gas engine will be OFF a lot of the time. Most days mine never starts because my daily driving does not exceed the battery range. I usually carry about 2-3 gallons of gas in the tank and sometimes the same gas is in the tank for 3-4 months because it is never used (except for a brief engine maintenance period every month or so). It is nice to see the 100+ miles of reserve range there if I need it though. And of course for a longer trip I just fill up the tank and go.
 

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Driving Vlot like a grandpa or like Jeff Gordon makes a huge difference in MPG. In my first 2 years of volt ownership I drove like a grandpa trying to eek out every mile. Then a switch flipped in my head and I reverted to driving like speed racer, my MPG dropped, but this car is so much fun to take on any and all pony cars from stop lights. I now ignore all the telemetry on the dash and just drive. It's much more enjoyable than the MPG and EV range game.
 

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I have a 2012 Volt. It isn't uncommon at all to get 42 MPG in it on long trips. I would think I could probably get 46-50 in a new Volt, not counting the electric only range.
My commute (which is only once every week or two; I work from home most days) is about 100 miles total, so I end up driving on gas close to half the way. My MPG figures for those commutes are in the high 40s (gas-only, of course), according to the car's computer. There is a major caveat, which is that I might be switching in and out of "hold" mode in a way that shifts energy use to the battery, vs. getting energy from gas. For instance, in order to reduce noise, I tend to accelerate up to highway speed on battery and then switch to "hold" mode to use the gas engine. To the extent that this is a factor in my getting such good MPG figures on gas, though, it's even more impressive in some ways, since in the early fall I was getting in excess of 60 miles of electric range on a charge in these commutes -- well in excess of the 53 miles of range that Chevy claims for the car. (The range has dropped now that the weather's gotten colder.) In other words, I was exceeding both the gas and electric fuel-economy numbers in the early fall. Now, in mid-November, I'm getting closer to the EPA estimates for electric range, but my gas MPG figures are still in the upper 40s.
 

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It won't do as good as a Prius on the interstate but you can beat or equal it on normal roads. We used to average about 40-44 MPG doing roughly 80 in our 2010 Prius and the Volt will pull around 38 or so, depending on hills. I have seen the Volt pull 60+ on side roads so you could probably cruise around town and equal a Prius pretty easily.

I'd like to get ours down to FL, we always got great mileage in the Prius down there.
 

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It won't do as good as a Prius on the interstate but you can beat or equal it on normal roads. We used to average about 40-44 MPG doing roughly 80 in our 2010 Prius and the Volt will pull around 38 or so, depending on hills. I have seen the Volt pull 60+ on side roads so you could probably cruise around town and equal a Prius pretty easily.

I'd like to get ours down to FL, we always got great mileage in the Prius down there.
I don't understand why people like to compare Prius blended gas/electric MPG to the volt gas only MPG. My volt shows 75 MPG lifetime on the dash, no prius can touch this. Many volt owners have 250+ on their dash. The only way to get better is to never hit the Dino juice (like Ari_C, leafs, Tesla's, and i3s without Rex)
 

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I don't understand why people like to compare Prius blended gas/electric MPG to the volt gas only MPG. My volt shows 75 MPG lifetime on the dash, no prius can touch this. Many volt owners have 250+ on their dash. The only way to get better is to never hit the Dino juice (like Ari_C, leafs, Tesla's, and i3s without Rex)
I believe for the average commuter it is a completely false comparison; however, for a person that has LONG daily drives it is definitely worth considering to understand all the angles. Also, the price of electricity plays a role here especially as gasoline has drifted much lower over the last couple years. Since gas is much lower at the moment, it is about even money, or even more costly for some people to drive the Volt in electric mode. Personally, I have solar so that never goes into my calculations. Having said all that, I simply couldn't imagine going back to an ICE after owning the Volt. ;)
 

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Greetings, Volters! I'm on the verge of buying a 2017 Volt - hopefully this coming Monday :D

I was thinking about the MPG rating of the gas engine, which I believe is 42 mpg. As an owner of Prius and Civic hybrids, I became adept at stretching the mileage ratings of those vehicles by 10% or more.

So, I was wondering if I could do the same with the Volt, but I don't think it's possible. Since the gas engine is basically an electricity generator, isn't it true that my driving skills wouldn't have an impact on the MPG? In other words, no matter how fast or slow I drive the gas engine will still spin at the same rate and use the same amount of gas while it's generating more electricity?

Or, does it slow down (or even stop) once the battery reaches a certain level of charge, and then if I drive judiciously and maximize the use of the battery it would delay a restart of the gas motor - thus improving the MPG?
Drive the Volt like you stole it and are running from the PD. This is the most fun. Don't worry about economy. Just plug it in when you can. The ICE is not as powerful as the electric motor, so it gets better performance with it off. You cannot force a Volt to suck at efficiency. It will always be better than cars with the same acceleration no matter how you drive it.

If you want to hypermile, all the same techniques apply:

Worn tires = good, LRR, highest pressure setting.
Reduce weight.
Reduce speed.
Use no brakes.
Accelerate slow, slow early.
Draft semi-truck on freeway.

That 53? miles advertised EV range can be slaughtered by hypermiling. The first week we got the 2016, I was in the mid-60's IIRC.
 

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The fundamental rules apply. Driving fast or hard requires more energy. In a Volt that energy is delivered to the wheels by electricity. (mostly) If you need more electricity the ICE will run longer and harder to provide it and burn more gas. If the car decides it is more efficient to have the ICE clutched to the wheels it will do so. Either way, in the end it's no different in principle than any other car.
 

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I drove from San Diego to Los Angeles area and back earlier this month. I had to use the gas engine for the first time. I went into hold mode when the traffic flow allowed me not to stop and go. I used battery during stop and go. 160 miles of gasoline driving and I average 52 MPG. Cruise control at 65 most of those miles.
I get 63 to 67electric miles each and every day on my 80 mile RT commute. I don't hypermile or piss people off behind me, but I do driver conservative speeds and try to coast into slowing traffic and keep space cushion (again, being mindful of not seeing the driver behind me turning red)
 

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I don't understand why people like to compare Prius blended gas/electric MPG to the volt gas only MPG. My volt shows 75 MPG lifetime on the dash, no prius can touch this. Many volt owners have 250+ on their dash. The only way to get better is to never hit the Dino juice (like Ari_C, leafs, Tesla's, and i3s without Rex)
A (non-plug-in) Prius uses one energy source: gasoline. Yes, there's an electric motor and battery, but the battery is charged from power generated by burning gasoline. (Regenerative braking in a Prius takes forward momentum and turns it into electricity stored in the battery, but that forward momentum was ultimately created by burning gasoline -- unless of course you're going downhill, but unless you live in M.C. Escher-land, a downhill run will be balanced by an uphill run.)

A Volt (or any other plug-in hybrid), by contrast, has two power sources: electricity (from the electric grid) and gasoline. The "MPG" figures that show total miles driven (whether powered by gas or electricity) divided by the gasoline used are therefore lies, because they ignore the power input from the electricity. That electricity has its own cost, so ignoring it and saying "I get 100 MPG in my Volt" is extremely deceptive.

IMHO, the best way to handle this issue is to split the Volt's energy efficiency measures in two: One for gas-only MPG and one for electric-only MPGe (or some other measure). Trying to combine the two figures creates too many variables, like how much driving you're doing on each energy source, the efficiency of the two motors, etc. Of course, keeping them separate also has its issues, but at least the in-dash computer keeps separate tallies, and each figure is likely to be closer to meaningful when comparing to another car. When you're comparing the Volt to a gas-only car like a Prius, you can then compare the MPG figures; and when comparing to an electric-only car you can compare the MPGe figures. In either cases, you can do a mental (or pen-and-paper, or spreadsheet) calculation of how much you're likely to drive on each fuel source and how much you pay for electricity to work out your likely total costs. Because electricity rates vary so much across the country (much more than gasoline costs), splitting things up this way is also more helpful in a national forum like this one.
 

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Like any vehicle, driving style affects the MPG.
My gen1 is rated at 38 MPG or something like that. But I average 45 on trips to the cottage in the summer.

But it could be 20MPG and it wouldn't really matter - it's not used 95% of the time, for me.
 

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We have both a 2010 Prius and a 2016 Volt. The Volt when running just on gas has been averaging over 45 mpg. Last trip, yesterday, the Volt from a cold start for 11 miles just on gas was 47.5 mpg. The Prius gets about 2-5 mpg or so more than the Volt on average. Most of our trips up to 200 miles or even more it is still less in fuel with all electric cost as well than using our Prius for the same trip. The Prius seem to take more of a hit during winter than the Volt when running on gas. My last fill up with the Prius, late fall / winter temps, was 48 mpg for comparison. That was calculated mpg's the Prius computer generated mpg is always over reading by 3 - 4.5 mpg than reality....
 

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With 6k miles on my '17 Premier, I only use the ICE (in Hold mode) on the expressway and only when I'm going for a distance that allows it to warm up thoroughly, not for short time durations. At 60-65 MPH, I consistently get 52-53 MPG. I engage Hold mode while accelerating on the on-ramp at about 45 MPH and disengage the Hold mode while coasting on the off-ramp. There may be other techniques, but that one puts me in the low 50s MPG every time.
 

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I just drove an 80 mile trip, I averaged 51 mpg. Like most everyone, I used electric to get on the freeway, switched to Hold mode while at speed, switching back to electric when traffic slows to a crawl, then back to Hold again when we get at speed again. Electric when off the freeway. I thought 51mpg was pretty good. Cruise control @ 67mph
 
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