Response to the news the Chevy Volt lost half it's range in cold weather driving

[erichmond]

I am a new roadster owner (two weeks). I live in Portland, OR which is pretty temperate. I was wondering if some of the owners in cold climates could comment on how the cold affects range on the roadster? If at all. Thanks.

[Lancelac]

In my experience, my Roadster gets about 90% of the range in the winter (below freezing), when compared to the same driving habits the rest of the year. For me, that is using the heat approx 50% of the time. It's also important to know that even though I drive in the cold every day in the winter, I do not park the car outdoors for more than an hour or so, which may improve my range since the car does not have the work as hard to warm the battery as it would if I did park outdoors all the time.

[Mitrovic]

My car is never parked outdoors, but I drive it everyday and the temperatures have been mostly around 0 degress Celsius. So far no significant drop in range I was able to detect...

[ChadS]

Here's a chart I made showing the effect of HVAC on range:

How far can you REALLY go in an electric vehicle? | Plug In America

[zack]

That's just so many kinds of cool. Thanks!

[benji4]

Here's a chart I made showing the effect of HVAC on range:

How far can you REALLY go in an electric vehicle? | Plug In America

What is the actual draw of the accessories? If we can compute the Wh/mi drain from the accessories, we can then get the actual decrease in range caused by them. For example, if you drive at 250 Wh/mi at 50 mph, and the accessories are using 10 Wh/mi, then you'd only see a 4% decrease in range (I think...). It would be interesting to see this calculation for each accessory: lights, stereo, heater, etc. I had all the accessories on last night (other than wipers) during a 40 mi drive mixed highway/city, but only lost about 38 mi of idea range, but I constantaly kept my eye on energy consumption and probably never got over 50mph or so, accelerated very slowly, no friction breaking, etc. I cheat a bit by turning off the heater about 1/2 the time though! I've kind of become obsessed with trying to squeeze range out of the car lately... I guess I need to get back to enjoying the car more!

[stopcrazypp]

Wh/mi will vary depending on speed. Remember, impact of accessories vary by TIME not DISTANCE. This is a critical point to keep in mind and explains why at lower speeds and with accessories on, you see dramatic drop in range (it is because at low speed you are driving for 8.5 hours on the battery, while at high speed you are driving less than 2 hours).

If you want to measure impact of accessories accurately, it's better to measure average power draw in terms of watts or kW.

[zack]

I don't have mine yet (arrives tomorrow... shivers!) but if you want to know what each accessory draws, can't you sit idle and monitor the KW meter while you turn on each one to see it change? Or is the meter so coarse that it doesn't show a change for smaller accessories?

[stopcrazypp]

Assuming the meter isn't too coarse, this may work pretty well for measuring always on accessories like the radio or headlights. However, for heating and cooling, measuring at a standstill might yield different results than moving. Also, usually when you start off the heat or AC will be blasting at the fullest level (worse case scenario), when what you really want to measure is the average.

[benji4]

One thing I did notice for sure is with heat, lights, etc., on, the Wh/mi reading does click up of --- but very, very slowly. It seems to me just from looking at how it moves though, that driving the car actually uses up much, much more energy than what the accessories are using. Obviously, the faster you drive, the less the impact of the accessories in exact proportion to your speed. It just feels from watching the meters like the accessories are not eating up that much power. That's logical when you think about the power that is needed to propell a 2,500 lb. automobilie.