Not to deflect, but I did a very similar trip today as yesterday, and that engine running due to low temp got me far better net mileage than I got today in 28 deg weather - big factor (my record yesterday was 31 mpg on gasoline part of the report, today, 17 miles and .7 gallons - 24 mpg). There appears to be the opposite of a sweet spot at temps just above where the engine will kick on automatically.
And this time, since the sun was out, I preconditioned the car. Still nasty numbers. ~~70 total mpg over the trip.

It seems driving slow/hypermiling is NOT what you want if the heater is on. You want to get there fast before the heater uses up all the battery by itself.

 

Not to deflect, but I did a very similar trip today as yesterday, and that engine running due to low temp got me far better net mileage than I got today in 28 deg weather - big factor (my record yesterday was 31 mpg on gasoline part of the report, today, 17 miles and .7 gallons - 24 mpg). There appears to be the opposite of a sweet spot at temps just above where the engine will kick on automatically.
And this time, since the sun was out, I preconditioned the car. Still nasty numbers. ~~70 total mpg over the trip
It seems driving slow/hypermiling is NOT what you want if the heater is on. You want to get there fast before the heater uses up all the battery by itself.

I see big differences between battery temperature and ambient....the battery is very well insulated. You can also see vigorous use pull the battery temperature up 5 degrees in 3 or 4 miles from self heating. Net, if your car is not sheltered, was charged the night before, hypermiling which does not heat the battery is not going to help much. I am talking about the 32 to ~60 degree battery range.
There isn 't much battery self-heating in the null range (no tms) from the cabin heater draw.

 

You guys are using the heater? I think I did the drive on Tuesday with 18-20*F range with fan only

My feeling is this cold snap will only last a week or two. No big whoop.

 

The alternative of not running the ICE would be ridiculously low EV range.* A prius gets low mpg's in very cold climates (upper 30's/low 40's) so you're still doing better at 65.





*I'm very interested to see what a Leaf with the upcoming cold wx package will do in Canada.

 

I'm very interested to see what a Leaf with the upcoming cold wx package will do in Canada.

What's that, a hot water bottle?

 

I'm getting an "awful" 65 MPG in Chicago too. So what? My lifetime is 140+MPG. Even at 65 during these winter months, that beats the heck out of other cars. When you can look at 65 MPG as disappointing, you know you are driving a whole new kind of car. The Volt has reset your MPG expectations to a whole new level, be happy. Winter will pass.

People on TV in Ford commercials are bouncing-off-the-walls happy to get 33-47. And we all kow those are at best under ideal conditions, at worst inflated by 10 MPG.

 

I'm getting an "awful" 65 MPG in Chicago too.

Same here, simply awful at 65 mpg!!!!!!!!!!!!!!!!!!! ;-)

 

Not running the heater when it's cold? I don't understand that. We paid a lot of money for a car with electric and gas engines. I'm not going to spend this kind of money and then be uncomfortable, just to try to maximize one engine over the other. Maybe I just dont get it.

My commute is such that I can just make it round trip on warm days (46 miles). If I have to burn gas for a couple of months, it's no big deal.

 

For me, I'm a polar bear. I grew up just north of Buffalo NY, did a lot of snow skiing and learned how to "command the wind" as a kid. Put on a nice jacket and if needed, gloves and I'm all set. I don't find driving in 20-25*F weather in the Volt cold at all. When my family wants it warmer, I'm uncomfortable. The material in the Volt seats appears to reflect heat a lot better than my old Mazda. One click on the seat heater may be all that I need below 30*F.

 

I live in DC area and am also quite upset about the engine running. With no option to allow to use electricity to heat the battery.

In my case I get free electricity at work and free at the gym so don’t use home electricity that much to charge the car. So this option would be useful for some.

However I did find some tricks after reading.

_ Do not use Fan only or ECO settings. This will cause the engine to run actually taking heat from the battery to heat car inside. In summer perfect not when very very cold. So you want to use the electric heater and then force the heat back into the battery.
- If you turn the climate off completely FAN OFF seems to retain the heat and drive briskly to heat the battery up.
- Comfort MODE fan set to 1 or 2 will lower electric range but I don’t care as I have free chargers at work gym etc. This will lower electric range but not use the gas engine except when pulling out.

So when really cold comfort mode is really ECO mode. I noticed something really annoying if you turn the cars climate control to off it will not remote start to the next day!

 

I live in DC area and am also quite upset about the engine running. With no option to allow to use electricity to heat the battery.
[...]
_ Do not use Fan only or ECO settings. This will cause the engine to run actually taking heat from the battery to heat car inside. In summer perfect not when very very cold. So you want to use the electric heater and then force the heat back into the battery.
- If you turn the climate off completely FAN OFF seems to retain the heat and drive briskly to heat the battery up.
- Comfort MODE fan set to 1 or 2 will lower electric range but I don’t care as I have free chargers at work gym etc. This will lower electric range but not use the gas engine except when pulling out.

I believe GM was acknowledging two issues:
1) They need to keep the battery above a certain temp. This requires heat. You will chew up all your electric range running the heat to keep the battery at temp so you can use your electric range...

2) the 6kw heater may be insufficient for cabin and battery heat when the temp gets that cold. Remember that "they made it for the masses" not the hypermiler.

I would think a better solution for this would be to tie the ERDTLT trigger to battery temp, not outdoor temp. In other words, have the generator kick on when the batter reaches x degrees, regardless of outside temp.

I guess this is the one Volt myth that just won't die.

Repeat after me:

"ERDTLT has nothing to do with battery temps. It's for heating the cabin."
"ERDTLT has nothing to do with battery temps. It's for heating the cabin."
"ERDTLT has nothing to do with battery temps. It's for heating the cabin."
"ERDTLT has nothing to do with battery temps. It's for heating the cabin."
"ERDTLT has nothing to do with battery temps. It's for heating the cabin."

 

I'm happy to be warm and drive it like a normal car. I typically use COMFORT and a FAN of lowest or 2nd to lowest setting. I have 3 of the vents pointed toward me. I use the setting of vent and feet typically but sometimes just vent.

Using COMFORT and lower fan speeds really keeps the ICE from coming on that often in the teens. When it was at 0 a couple days back it came on more.

Again I'm thrilled with great "MPG Used" still and to drive it like a normal car.

These low temps 10s are not that common and don't last long so overall I'm still getting excellent mileage.

 

I am enjoying the good heat and not worrying about it. The last time I fueled up was Feb. 2012 and I have about 3 gallons in the tank that will have to be burned off soon anyway for FMM. So send in the Comfort.

 

Just to clarify... Cold way up north is not exactly correct. East would be better. I'm sure my neighbors directly south of me in Seattle & Portland can tell you, the west coast rarely sees much more than frosty mornings. Certainly not cold enough for the ice to come on. We, however, are are plagued with a different form of battery drain this time of year.. wipers & defog.

 

Not being affected by really cold weather, I can see people being a bit frustrated, but you need to look at the big picture, the whole year and your average MPG. I basically look at how much gas I use per month/Year over an ICE car. I know that for every sub 30 Miles per Charge, I'll have equal amount of days over 40, and in my specific case - much more days over 40.

Cold affects every type of car's mileage, so does extreme heat.

I've driven about 1,000 miles on gas and used 28 gallons, but over all around 4,400 miles. Still only 28 gallons of gas.

This I believe is the reason we buy a Volt? Not really outrageous MPG, but overall how little gas we use comapred to any other car on the road without range anxiety.

 

All of you have great points! (and supportive btw )

Having used 7 gallons (dealer filled) of gasoline in over 9 months I probably don't have a good enough reason to complain huh?

Maybe the Volt just spoiled me I don't know.

 

What is the main purpose of ERDTLT and why is it mandatory? In other words, why didn't GM make it so the user could turn it off completely? Is it because the electric range would literally go down to <10 miles in a very cold situations without the generator?

 

I believe GM was acknowledging two issues:
1) They need to keep the battery above a certain temp. This requires heat. You will chew up all your electric range running the heat to keep the battery at temp so you can use your electric range...

2) the 6kw heater may be insufficient for cabin and battery heat when the temp gets that cold. Remember that "they made it for the masses" not the hypermiler.

 

I too have the COLD BLUES. My biggest complaint isn't that the ICE runs to heat the battery, it is that the 2013's can select very cold (-10C) before the ice comes on and my 2012 comes on at -4C. When I have talked to the Volt reps they are positive that a software update won't work because it requires a hardware change! Really! Both cars have a theromastat, both cars run a if/then loop for the program. Just change the temp in the setting to solve at least part of our problem. At less than -10C I want my ICE on for heat. Above that I can cope.

So where exactly is the thermometer that reports the temp. I would love to trick it too thinking it is say 6 degrees C warmer. While I am on a rant, where is my damn Hold button! Needs hardware my butt. There is even a space for it below Mountain Mode on my display already!

Rant over.

 

Now that it is icey cold out, my ICE is running about 1/2 the time and it is keeping me nice and warm, fan only!

I like getting the maximum use out of the energy, from the gas I have to burn.

Yes, it hurts the numbers, but remember, they are just numbers.

 

My 20.5 mile commute this morning in 11 degree temp resulted in I believe 4 ERDTLT runs for a total of 2.9 miles on ICE with the climate off. I ran 2 pre-conditions before pulling out of my garage which was about 45 degrees.
I went less then 0.5 miles an theERDTLT ran (Really! was that necessary). I am positive I will not make it home on all EV, since the temp will be below 18 (usually make it) and I am parked on a street near the office and will not precondition for the commute home. The outside temp will be above 15 so at least no ERDTLT.

 

Correct me if I'm wrong, but ERDTLT is only a function of the outside air temp correct? Preconditioning doesn't effect it.

I do agree for the customers who treat the Volt as a BEV, we should consider making ERDTLT completely at the users option. EMM, that's another story. We have to protect the engine from future warranty issues.

Personally, I think we underestimated the number of customers who really wanted a BEV and bought the Volt because it's the best one out there. Even if you have to lug around an engine that you would rather NEVER ran.

 

Correct me if I'm wrong, but ERDTLT is only a function of the outside air temp correct? Preconditioning doesn't effect it.

Well, in a way it can - and did for me today for the first time.

Yesterday I preconditioned twice, then came out - and ERDTT hit immediately when I started the car (and a second time as I pulled in to the grocery store.)

Today, for some reason (don't think much was different,) when I came out the engine was silent, even though we were slightly below the threshold OAT.

When I turned on my DashDAQ, I figured out why - coolant was at 135F; the engine had run during the precondition (which hasn't happened to me before - Delaware didn't have much winter last year, and for some reason today was different from yesterday...)

With the marginal temperature, Comfort was enough to keep the engine off for the whole drive home (only 10 miles) - so preconditioning prevented me from experiencing ERDTT at all (though it happened without me before I got to the car.)

 

I think decision to buy the Volt over say the Leaf was because we thought we could use a lot less gas overall. If I thought I'd NEVER use gas, I'da bought a Leaf... if it looked more like a Volt.

 

Try to not let the winter weather get you down. The next two weeks are the coldest of the year; after that the temperatures get steadily warmer.

 

Use COMFORT mode to maximize electric range on trips that won't use your full battery anyway. It's counter-intuitive, but using Comfort mode reduced ERDTLT time as it helps keep the fluids warm. It's surprising how much less the engine cycles at a given temperature when Comfort mode is used compared to Eco or Fan only.

And it has a nice side effect of actually keeping you die-hard EV drivers WARM!

 

I feel like I've said that until I'm blue in the face and it is not from being cold!!

I'm happy to be warm and drive it like a normal car. I typically use COMFORT and a FAN of lowest or 2nd to lowest setting. I have 3 of the vents pointed toward me. I use the setting of vent and feet typically but sometimes just vent.

Using COMFORT and lower fan speeds really keeps the ICE from coming on that often in the teens. When it was at 0 a couple days back it came on more.

Again I'm thrilled with great "MPG Used" still and to drive it like a normal car.

These low temps 10s are not that common and don't last long so overall I'm still getting excellent mileage.

 

It would appear that the ERDTLT is triggered by outside air temp (<-4C in my 2012) and coolant temp. I have noticed that the ICE cycles on once the coolant temp drops to 48C and shuts off at 63C. Then repeats, repeats and repeats. Using comfort mode increases the time between cycles thereby saving gas.

 

Thank goodness for an inefficient ICE when the temperature is hovering around 0 F.

I for one am quite happy to have an inefficient, heat producing ICE this past week when it has been hovering around 0 F. It is one thing to drive around with Fan only and electric seat heaters when the temps are near freezing, but when the temperatures are life-threatening, it is nice to warm up the car with the energy stored from the dinosaur age. Even with these cold temps, I have still been hitting around 80 MPG for my 37 mile trips and only using 0.25-0.4 gallons of gas.

To the critics, show me another car with mileage numbers to match the Volt at these temps. In my Ford Escape Hybrids, I lose about 1 MPG for every 10 degree drop in temperature.

 

Page 5-44 of the 2013 Owner's Manual under "Vehicle Messages - BATTERY TOO COLD, PLUG IN TO WARM. This message displays during extremely cold temperatures when the vehicle will not start until the high voltage battery is warm enough. Plug the vehicle in and make sure the power button is off to allow the charging system to warm the high voltage battery, then the vehicle can be started."

What does "extremely cold" mean? Right now it is cold (extremely cold?) where I drive my Volt. It sits in a warmish garage on a level II charger late at night but during the day it could be in a parking lot for many hours where it is cold and charging is not an option. At what cold temperature do you start wondering if you will get the "BATTERY TOO COLD" message?

 

From a previous post:

"Here's a relevant excerpt from an April 2011 GM Techlinks publication. (Also keep in mind that the latest battery cells in 2013 Volts have an even lower temperature threshold than the -14F/-25C described below):

http://www.sandyblogs.com/techlink/April 2011 Techlink F.pdf

"If the "Battery Too Cold, Plug In to Warm" message is displayed on the Driver Information Center of the 2011 Volt, the vehicle will not start until the high voltage battery is warmed up. This condition usually occurs on vehicles that have been parked for a prolonged period of time in extremely cold temperatures (approximately -14°F or -25°C).

When the vehicle is subjected to cold temperatures for an extended length of time, the electrolyte in the high voltage battery cells starts to freeze. Once this occurs, current cannot pass through the battery for any reason, such as starting the gasoline engine or powering the battery internal heater. It is a physical limitation much the same as diesel fuel gelling at very cold temperatures and making the vehicle impossible to start.

If this condition occurs, advise the customer of the physical limitations of the high voltage battery and that this is a normal condition. Plug in the vehicle to allow the charging system to warm the high voltage battery, and then the vehicle can be started.
Without a charger to provide power from somewhere besides the high voltage battery, the contactors cannot be closed and the vehicle cannot be started. The Volt does not have a conventional 12V starter and needs the high voltage battery to supply voltage to the electric motor to start the gasoline engine.""

 

Using ECO mode averaged 85 MPG.
Using Comfort mode 168 MPG.
Northern Illinois Temps around 15 deg.

 

Great data! I was recently in -5F and Eco mode and was surprised how often the ICE was running.

Question: what are the numbers for Comfort vs Eco mode in hot weather? Is ther any reason really to not use Comfort year-round?

 

Also to mention, ERDTT may be different for 2013 vs 2012,2011. During my ERDTT, the ICE coming on powers the traction motor so my EV range does not decrease while it is on (although it does absorb regen).