That's good news on the gas mpg! I love driving EV (I love sport mode by the way) but I know there will be multiple 100+ mile trips coming up so good to know the gas mpg is pretty good. Does anyone have any tips on cold weather driving and the Volt? Preconditioning, cabin temp, etc...While I like to get as much as I can out of the battery, I'm not crazy and like warmth. I should probably not think so hard about it and just drive...
If you can precondition your Volt while plugged into a Level 2 EVSE you can warm the battery and the cabin by the time the 10 minute preconditioning cycle is completed, another 5 or 10 minutes charging after the preconditioning cycle completes will top off the battery. You can extend the 1st precondition cycle for an additional 10 minutes or run a second 10 minute cycle but after that you have to manually start the Volt. You will have to experiment but start by setting the climate control between 82F and Maximum, setting the climate control to recirculate the cabin air; following preconditioning your Volt will be warm when you enter the cabin.
If your Volt has electric seats these will help keep you warm and use very little battery power while in use. If your Volt has the optional heated steering wheel you will find it very effective at warming the part of your hands that touch the steering wheel. The electric seats can be set to automatically come on and will start to warm the front seats while the preconditioning cycle is running and anytime the Volt is powered on. In my experience the Volt's cabin will remain reasonably warm after preconditioning for perhaps 15 minutes. After that you have to decide whether to use the electric heat or engage Hold mode to start the has engine. Anytime it is below 15F the Volt will automatically cycle the gas engine to generate some heat for the cabin.
Understand how the Volt's Engine Assist Heat functions. The default setting will have Engine Assist Heat start to cycle the gas engine on and off to warm the cabin when the outside temperature is below 35F. You can defer the Engine Assist Heat (this can be done within the settings) so that the Volt will only start the gas engine when the temperature is below 15F. Engine Assist Heat is designed to heat the passenger cabin, not the battery. The battery temperature is maintained by drawing power directly from the battery.
If you park outside while charging you may want to set Engine Assist Heat Plugged In to be On or else if you park in a garage you should set Engine Assist Heat Plugged In to be Off so that the gas engine will not start inside a garage while preconditioning in cold temperatures. Anytime the Volt is plugged in the Volt's battery management system will heat or cool the high voltage battery to maintain the battery temperature within an acceptable range (40F - 64F) in cold weather. In my experience, in hot weather the Volt will automatically cool the battery when the battery temperature reaches ~95F, perhaps lower while charging.
For trips of up to 30 - 35 miles you should be able to complete the trip on battery even when the temperature drops below 32F. You can of course decide to use Hold mode at any time. This will save the battery remaining charge and will burn gas to propel the Volt. Hold mode will also generate heat for the cabin.
Cold weather driving in MN means much colder temperatures than here in MD. The coldest overnight (garage) temperature and daytime temperature I experienced in my Volt last winter was ~20F. The Engine Assist Heat kicked in one time when I was picking up my Volt from the dealer's service department. The dealer had reprogrammed the Volt, this reset the Engine Assist Heat to the default setting of 35F and the gas engine started as soon as I started the Volt.
I usually exceed the Volt's 42 MPG combined city/highway fuel economy but in cold weather I've seen fuel economy when using gas drop into the low 30s.