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Discussion Starter #1
We've been very happy with our Volt, but now that gas is getting cheaper and electric range is going down for the winter, I decided to review the numbers it's a bit depressing. No wonder they're having trouble selling these cars in this area.

I'm getting around 40kwh/100 miles reported by Onstar. At $0.23 per kwh, that's 9.2 cents per mile.

Gas is averaging 2.61 per gallon, at 40 mpg that's 6.5 cents per mile.

I love the convenience and reducing our dependence on oil, but the numbers don't lie. And most of our electricity comes from hydrocarbons anyway (natural gas primarily). So, what's the point? Thinking I may just stop using our at-home charger unless the situation changes. Anybody else have similar thoughts?

For what it's worth, I'd still buy one again (might still, in fact, they're basically giving them away). The electric torque is amazing, and it's good insurance for the next geopolitical crisis.
 

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We've been very happy with our Volt, but now that gas is getting cheaper and electric range is going down for the winter, I decided to review the numbers it's a bit depressing. No wonder they're having trouble selling these cars in this area.

I'm getting around 40kwh/100 miles reported by Onstar. At $0.23 per kwh, that's 9.2 cents per mile.

Gas is averaging 2.61 per gallon, at 40 mpg that's 6.5 cents per mile.

I love the convenience and reducing our dependence on oil, but the numbers don't lie. And most of our electricity comes from hydrocarbons anyway (natural gas primarily). So, what's the point? Thinking I may just stop using our at-home charger unless the situation changes. Anybody else have similar thoughts?

For what it's worth, I'd still buy one again (might still, in fact, they're basically giving them away). The electric torque is amazing, and it's good insurance for the next geopolitical crisis.
The Volt will only achieve 40 MPG+ using gas once the engine has had a chance to fully warm up. You would need to drive at highway speeds for at least ~8 - 10 miles to get the engine coolant warm. 12 - 15 miles would be even better.

For short trips just use the battery. If you precondition while plugged in you can be warm as you start driving instead of waiting for the gas engine to warm up.
 

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Running on gas will increase your maintenance costs (more frequent oil changes), plus you lose the value of your time spent to get them done. It also causes less driving satisfaction with the added engine noise and exhaust fumes. And even though your grid electricity may be powered by hydrocarbon, it is still a lot cleaner and lower carbon overall to use that instead of burning gasoline. Many owners continue to charge in your situation for those reasons. But the choice is yours.
 

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2 questions:
1. When did Mass electric rates hit $.23/kWh?! I thought $.16 was rough here in NH. Have you looked into alternate suppliers?

2. Are you really averaging 40mpg in the colder weather? I know my mpg drops quite a bit during the winter.
 

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Discussion Starter #5
2 questions:
1. When did Mass electric rates hit $.23/kWh?! I thought $.16 was rough here in NH. Have you looked into alternate suppliers?

2. Are you really averaging 40mpg in the colder weather? I know my mpg drops quite a bit during the winter.
1) In my area (Boston) rates have hovered around $.23 for quite some time. Most of the charge is in fact the delivery - roughly $.12 per kwh. We can choose our supplier but not the delivery. Tough to get much below $.11 for supply. NH has the same supplier (Eversource) but cheaper rates. Go figure. Just looked it up and current NH Residential rates $.182 per kwh plus $12.69 customer charge.

2) Not quite, but close. Too be fair, most of our local driving is on electric and so most of the gas miles are "highway miles". I'm sure that would change if we switched to gas only. We put a LOT of miles on the car, as my fiance uses it for work trips. Example from our latest (December) report... 793 electric miles driven at 44kw/100 miles. 896 gas miles driven. "71 mpg total". Doing the math I figure that's 23.8 gallons used over 896 gas miles, or 37.6 MPG.

So even using those numbers that's 10.1 cents per mile under electric and 6.9 cents per mile under gas.

Put it another way, using electric is costing me about the same as driving a vehicle which gets 25 mpg using gasoline.
 

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1) In my area (Boston) rates have hovered around $.23 for quite some time. Most of the charge is in fact the delivery - roughly $.12 per kwh. We can choose our supplier but not the delivery. Tough to get much below $.11 for supply. NH has the same supplier (Eversource) but cheaper rates. Go figure. Just looked it up and current NH Residential rates $.182 per kwh plus $12.69 customer charge.

2) Not quite, but close. Too be fair, most of our local driving is on electric and so most of the gas miles are "highway miles". I'm sure that would change if we switched to gas only. We put a LOT of miles on the car, as my fiance uses it for work trips. Example from our latest (December) report... 793 electric miles driven at 44kw/100 miles. 896 gas miles driven. "71 mpg total". Doing the math I figure that's 23.8 gallons used over 896 gas miles, or 37.6 MPG.

So even using those numbers that's 10.1 cents per mile under electric and 6.9 cents per mile under gas.

Put it another way, using electric is costing me about the same as driving a vehicle which gets 25 mpg using gasoline.
That may be so, but it's costing the environment less. Personally, that's the #1 reason we bought our Volt.

I would be disappointed to be in your situation, but would still continue to maximize electric use over gas.

No doubt low gas prices are making EV's a harder sell.

Sent from my SM-G930V using Tapatalk
 

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Use mountain mode. Higher state of charge will give you better performance and the battery will last longer.
 

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Use mountain mode. Higher state of charge will give you better performance and the battery will last longer.
Where did you find information that using Mountain Mode will give better performance and increase the life of the battery.

Mountain mode uses more gas than running on the battery and then running on gas.
 

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Where did you find information that using Mountain Mode will give better performance and increase the life of the battery.

Mountain mode uses more gas than running on the battery and then running on gas.
The Volt is just a little bit lazy with a fully depleted battery as the cell voltages are lower so the acceleration is better at mountain mode state of charge and this can be proven.

Lithium Ion batteries last longer if they are not fully depleted or fully charged. The Volt already buffers the extreme charge conditions but a little more on the low end will help even more.

The fuel consumption is irrelevant on this point.
 

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The Volt is just a little bit lazy with a fully depleted battery as the cell voltages are lower so the acceleration is better at mountain mode state of charge and this can be proven.

Lithium Ion batteries last longer if they are not fully depleted or fully charged. The Volt already buffers the extreme charge conditions but a little more on the low end will help even more.

The fuel consumption is irrelevant on this point.
Since the Volt's battery pack is never fully discharged, how much of an increase in the life of the battery can be had by adding to the low end of the buffer? 1-2% 5% 10%? Where is the data?

Fuel consumption is relevant as this is related to the title of the thread.
 

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Those electric rates are scary! My home is in a suburb, but power is supplied by a semi-rural co-op. Cost per KW ranges between 11.5 and 12.5 cents, plus we get a summer discount for placing our AC on a peak load cycling program and a dividend (small) each year as members of the co-op. Even with the winter range reduction, the Volt cost per mile is very low.

But - my daughter has a 2017 Prius that gets fantastic mileage. She just bought gas at Costco for $1.99, so with those prices her Prius is probably equaling or even beating my Volt on a per-mile basis. No wonder the US is buying pickups and SUVs - but the pendulum will eventually swing back again, the Mideast will go (more) crazy and we will see gas back in the $3.00+ range.
 

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Discussion Starter #13
Where did you find information that using Mountain Mode will give better performance and increase the life of the battery.
I've seen a variety of sources that state that optimum storage conditions for a lithium battery is 40% SOC and 60F. So it makes intuitive sense that mountain mode (or hold mode) is better for the battery long term than simply letting the battery deplete to the lowest level the car allows, assuming that one wants to run around as a "regular" hybrid.

Incidentally my neighbor has a plug in BMW X5 which AFAIK has never been plugged in. Must have just bought that option for the tax credit. Massachusetts is doing away with their $2500 state rebate for plug-in hybrids starting January 1st, combined with local dealership offering $10,000 off the price, which is why I'm considering jumping an another Volt in the next few days. Would feel almost dishonest to get the credits and rebate and then not even plug in.
 

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I think we are discussing two different cases. The first is whether to drive the Volt with a depleted battery (showing 0 bars) using charge sustaining mode or to use Mountain mode to build up some amount of charge while driving.

The second case is the best SOC for the life of the battery. GM already addresses this by stating that if you will not be driving the Volt for longer than 4 weeks (30 days) that the Volt should be stored, unplugged, with 3 bars (30%) state of charge
 

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Discussion Starter #15
I think we are discussing two different cases. The first is whether to drive the Volt with a depleted battery (showing 0 bars) using charge sustaining mode or to use Mountain mode to build up some amount of charge while driving.

The second case is the best SOC for the life of the battery. GM already addresses this by stating that if you will not be driving the Volt for longer than 4 weeks (30 days) that the Volt should be stored, unplugged, with 3 bars (30%) state of charge
What I am discussing is if you want to *never* plug in the car, because electricity is too expensive. In that case the postulate is that using "mountain mode" full time will maintain the SOC at around 40% which is best for battery longevity (and also performance).
 

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What I am discussing is if you want to *never* plug in the car, because electricity is too expensive. In that case the postulate is that using "mountain mode" full time will maintain the SOC at around 40% which is best for battery longevity (and also performance).
Ok; to be clear the 40% SOC for Mountain Mode (MM) only applies to a Gen 1 Volt. For the Gen 2 Volt MM only maintains a SOC of 2 bars (15 - 20%). So perhaps for the best overall driving and fuel economy where you won't ever (or rarely ever) plug in to recharge, for the 2013 and later Volts that support Hold Mode, it is better to switch to Hold Mode once the battery SOC reaches 40 - 60%. The rare time it would make sense to plug in is at a free public charging station.
 

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Discussion Starter #17 (Edited)
FWIW, I made this graph using the OnStar data for the last year. I used the "December" report for November, etc, because the report is for the preceding months usage.

It shows the "MPGe" I calculate for Boston Electric rates and assuming various gas prices. My conclusion is that gas has to go up quite a bit to justify using electricity in the winter, but during the summer months it still makes sense, but just barely.

EDIT: seems to have shrunk my attachment, making it hard to read. The red line is 2.61 per gallon, yellow 3.00 per gallon, green 4.00 per gallon.

pubchart.jpg
 

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A lot of states have an hourly or variable pricing program available through their electric utility. Usually rates at non peek hours like 12:00 AM to 5:00 AM can be anywhere between 3 to 0 cents per kilowatt hour. Smart meters are installed for this pricing program to be available. Down side is keeping air conditioning usage to a minimum during peak hours during the summer.

Been on ComEd's hourly pricing program in Chicago and save 33% vs standard pricing. My Volt charges on average at 1.8 cents per kilowatt hour vs flat residential rate of 7.3 cents per Kilowatt hour. There are occasions where you are credited for usage after 12:00 AM during the colder months of January and February.
 

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My solar generates more than my car uses and a couple of charge stations I use occasionally are free. I think I'm still a bit ahead of the game with current gas prices, less frequent engine maintenance, and less time taking trips to the gas station. It could also be argued I'm helping to mitigate climate change, etc. vs. the car the volt replaced.
 
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