How much of a drain on battery life will heating the car up be when it’s well below freezing outside in the morning?

Does the passenger compartment have greater thermal insulation than a normal car to reduce this energy loss?

Presumably if the car is plunged in overnight, then the cars heating system could automatically warm the car up at a user programmable pre-set time in the morning using electricity supplied directly from the plugged in cable and not the car’s batteries. Thus (besides increasing range) making the car nice and toasty (with defrosted windows) when you start off on your journey to work on a cold dark winter morning. A definite selling point for those of us climatically disadvantaged.

There is not significant difference whether you think the AER will be 32 miles or 45 miles, provided the 8 KWh is used up in about the same period of time.

If your point is that my estimate was a rough order of magnitude estimate, that is true. These (ROM) estimates are expected to be in the ball park, not design calculations.

If the drive cycle lasts about one hour, then 1.25 KWh will go into the AC, leaving 6.75 to drive the wheels. Without the AC, 8 KWh is available to drive the wheels. Thus about a 15% reduction in the AER.

I remember the thread you mention, but you have to remember that the Volt will most likely perform better, if not much better, than what Bob drove. That was the guts of the Volt, true, but not in a Volt body and also without the all important software to manage the battery.

GM has staked FAR too much on the 40 mile AER for them to not make it. I’m fully confident that the Volt will give me a full 40 mile AER for ten years or more…..of course, when you turn the AC on it will diminish the range somewhat, but hey, my G6 is rated for 23 city/30 highway. With the AC on high it’s actually more like 21 city / 32 highway (I know, the car actually gets about 34-35 mpg highway without the AC on). My point being, you will rarely, if ever, get the mileage posted for a car, unless you try to. Its much more of an estimate than an exact figure, always has been and always will be.

You could have it warmed up off of your home power in the morning while plugged in, then it will not take as much energy to maintain a warm temperature in cooler weather. The same with cooling – the largest load on a vehicles AC system in hot weather is cooling the interior. Once it’s cool, maintaining a cooler temperature is not as energy intensive.

One thing I’ll be glad about is that if I were able to get a Volt in a couple years, both at home and at work, I can park in a garage, so the car will not be exposed to the hot Texas sun all day while I’m at work.

I believe we can replace gasoline very soon, and with cars like the Volt. Remember that the Volt also runs on E85. Although corn ethanol sucks (never understood why they did that), other sources of ethanol are perfectly viable. See here for details:
http://www.coskata.com/EthanolFeedstockPotential.asp

Bottom line:
EREVs + Ethanol can completely replace gasoline, and both are within our reach.

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Dave, when you review this site, you need to read with much more skepticism. The site owner merely claims that third party analysis indicates that his cost target of $1 per gallon is the best cost target in the industry. It does not offer ethanol for sale at $1 per gallon, or at any price. It offers no evidence whatsoever that that cost target will ever be achieved.

While the laws of physics and chemistry, as we understand them today, do not rule out low cost mass produced cellulosic ethanol, no clear path to that goal has been identified.

The beauty of range extended electric vehicles is that they involve little or no speculative technology. There is plenty of evidence to show they will work, and this thread simply quibbles about “suppose you are in Arizona on the hottest day of the year, do you get 35 miles or 40 miles AER”?

Tesla has a good post on their blog about energy consumption, speed, and range: http://www.teslamotors.com/blog4/. The Volt won’t be the same but should be similar. I would expect the auxiliary loads to be a little less and the overall efficiency to be a little better for the Volt but the Roadster weighs a little less. The CdA should be pretty similar as well. As you can see from the graph on the Tesla link, energy use will be about 140Wh/mile for 20mph travel or 57 miles/8KWh without AC. Getting back to my assertion that real world commuter driving in moderate to heavy traffic will yield 45-38 miles AER at 55-75mph. Tesla uses 230-330Wh/mile for 55-75mph speeds. This is based on traveling through “still” air and translates to 35-24miles/8KWh. Notice the aerodynamic for this speed range is 100-170Wh/mile. If the disturbed air in traffic reduces aerodynamic load by 50% (admittedly just a swag), then the total load range becomes 180-245Wh/mile which gives 44-33miles/8KWh. I try to find a study about aerodynamic affects of traffic but regardless commuting in traffic at 65mph is going have significantly more AER than calculations for still air driving predict, including EPA highway cycle.

Lets say the average speed for the cycle was 20 MPH and took two hours and the average draw was 1 KW for the AC so the AC would burn 2 KWH leaving 6 for an AER of 30 miles. Or, if we could get 3.5 miles per KWh at 60 MPH, then you would burn through the 8 KWh in 40 minutes, so the AC would draw 1.25 kw on average (cooldown being a significant fraction of operating time) and you total range would be about 25 miles.

So you are faced with a trade-off, where going to slow results in high AC loss, and going to fast results in high drag loss. The sweet spot I believe will yield about 28 miles of AER with the AC on.

And that is about 15% less than the 32 AER I expect using 8 KWh in real world driving.

You mean about 15% reduction for about 1KW AC load if averaging about 40mph, correct?

And yes again for your source indicating 1 KW for the steady state draw. Note (post # 150) indicates the draw will vary from .9 KWh to 1.6 KWh based on the Prius electric AC unit, so if we use 1.25 KWh for the average draw because of the initial cooldown, the AER will be decreased by about 15%.