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AC, lights, stereo, power steering, ABS, Airbag, OBD, trip/idiot/diags, and dashboard/running/interior lights.

What does the AC use?
 

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Don't have the figures. But I think you meant their kW (unit of power) rating instead of kW/h (not really a common unit except in dimensional analysis or coefficient of some models). And for the energy consumed, we simply multiply the total average wattage of all appliances used by the total time used to get kWH consumed.
 

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The way I figure the Volt uses 12.8 kW to go 64 miles, so figuring that we are cruising at 64 in Phoenix on a Summer night, and that the battery will actually last an hour, during that hour how many kW did the accessories burn?
 

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The way I figure the Volt uses 12.8 kW to go 64 miles, so figuring that we are cruising at 64 in Phoenix on a Summer night, and that the battery will actually last an hour, during that hour how many kW did the accessories burn?
Not meant to be nitpicking on you, and it is my fault for not being too clear in my first response, but I think this time you meant kWH (energy consumed )as opposed to power (kW units). 12.8 kWH gets you 64 miles, that is exactly correct rating of the Volt, which comes to 5 miles per kWH at "normal" driving profile.

For sure, the AC would consume the lion share of the energy of the accessories. I would estimate that the AC would consume about 0.5 kWH for the one hour and 15 minute trip. I don't have the official specs, so this is just my speculation on the estimated energy consumption. I am not even sure if the AC will be running pure electric or directly run by the genset.
 

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Average Accessory Power

I assume that there will be a separate 12/48V battery for accessories. You would need this for "limp home" capability for the case where the power train battery died and you needed to turn-over the ICE and power its electroncis. The figures below are all "best guesses." Correct them as better info becomes available.

Battery Only Mode (No ICE Operating Power) Accessory Power Drain (W)
Accessory, Power, Duty_Cycle, Avg_Power
A/C – Heating (Heat Pump) 700 0.8 (Seasonal) 560
Control Electronics 100 1 100
HVAC Air Blower 10 0.8 8
Display Lights 3 1 3
Headlights – Low Beam 55*2 0.2 22
Headlights - High 120*2 0.1 24
Tailgate LED Lights 5*4 1 20
Interior Lights 1*4 0.2 1.6
Power Steering 10 0.5 5
Brake Hydraulic Pump? 10 0.5 5
Battery Case Blower 20 1 20
Battery Case Electronics 50 1 50
Cooling Fan 20 1 20
Wipers 10 0.1 1
Stereo 20 0.5 10
DVD 10 0.2 2

Total BEV Average Power 850W
 

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I assume that there will be a separate 12/48V battery for accessories. You would need this for "limp home" capability for the case where the power train battery died and you needed to turn-over the ICE and power its electroncis. The figures below are all "best guesses." Correct them as better info becomes available.

Battery Only Mode (No ICE Operating Power) Accessory Power Drain (W)
Accessory, Power, Duty_Cycle, Avg_Power
A/C – Heating (Heat Pump) 700 0.8 (Seasonal) 560
Control Electronics 100 1 100
HVAC Air Blower 10 0.8 8
Display Lights 3 1 3
Headlights – Low Beam 55*2 0.2 22
Headlights - High 120*2 0.1 24
Tailgate LED Lights 5*4 1 20
Interior Lights 1*4 0.2 1.6
Power Steering 10 0.5 5
Brake Hydraulic Pump? 10 0.5 5
Battery Case Blower 20 1 20
Battery Case Electronics 50 1 50
Cooling Fan 20 1 20
Wipers 10 0.1 1
Stereo 20 0.5 10
DVD 10 0.2 2

Total BEV Average Power 850W
Please keep in mind you can run 80 MPH on flat ground or 60 MPH up a 7.92% grade in "limp home" mode.

They will probably have an accessory battery even though the only time you will really need it is when you are sitting in the car watching the big game while the wife is in the store shopping. The only way I would let my wife drive a $40,000. car is if the body was armored. Hey KITT, where are you?
 

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Limp Home Performance Simulation

Please keep in mind you can run 80 MPH on flat ground or 60 MPH up a 7.92% grade in "limp home" mode.
If you use a generator output of 53 kW, define road grade as a function of arc tangent, and define max speed as the speed at end of 60 seconds, then my Volt simulation gives a maximum speed, without and with a 7.92% road grade, as 80 and 55 mph, respectively. I used 60 seconds because unless you have a very smooth and straight road on a windless day, I don't think you can realistically keep the road surface, grade, straight direction, and banking and wind conditions constant for any longer period of time at high speed.

The Volt motor has a peak power capability of 209 hp (latest web info), but in the "limp home" mode this is limited by the generator to 71 hp. Attached are the simulated performance curves at 7.92% road grade "limp home."
 

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what are your assumptions?

If you use a generator output of 53 kW, define road grade as a function of arc tangent, and define max speed as the speed at end of 60 seconds, then my Volt simulation gives a maximum speed, without and with a 7.92% road grade, as 80 and 55 mph, respectively. I used 60 seconds because unless you have a very smooth and straight road on a windless day, I don't think you can realistically keep the road surface, grade, straight direction, and banking and wind conditions constant for any longer period of time at high speed.

The Volt motor has a peak power capability of 209 hp (latest web info), but in the "limp home" mode this is limited by the generator to 71 hp. Attached are the simulated performance curves at 7.92% road grade "limp home."
Nice curves!

What values did you use for C_d*A and rolling resistance? Can you provide the simulation code? How again have we defined "limp home" mode?
 

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what are your assumptions?

If you use a generator output of 53 kW, define road grade as a function of arc tangent, and define max speed as the speed at end of 60 seconds, then my Volt simulation gives a maximum speed, without and with a 7.92% road grade, as 80 and 55 mph, respectively. I used 60 seconds because unless you have a very smooth and straight road on a windless day, I don't think you can realistically keep the road surface, grade, straight direction, and banking and wind conditions constant for any longer period of time at high speed.

The Volt motor has a peak power capability of 209 hp (latest web info), but in the "limp home" mode this is limited by the generator to 71 hp. Attached are the simulated performance curves at 7.92% road grade "limp home."
Nice curves!

What values did you use for C_d*A and rolling resistance? Can you provide the simulation code?
 

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Prius vs. Volt accessory power budget and limitations

The Prius, being a parallel hybrid, has a fat accessory power budget. The Volt has a battery with an available energy of 8 kWHr. 2-5 kW just for accessories would reduce the Volt single charge range to a small fraction of this. One of the big challenges for Volt designers has been to develop highly efficient accessories, such as a heat pump. After having said all the above, remember that all I claim for my numbers is that they are "best guesses." Also note that my numbers are for average power, not peak power.
 

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For sure, the AC would consume the lion share of the energy of the accessories. I would estimate that the AC would consume about 0.5 kWH for the one hour and 15 minute trip. I don't have the official specs, so this is just my speculation on the estimated energy consumption. I am not even sure if the AC will be running pure electric or directly run by the genset.
Toyota has announced using solar cells embedded in the roof to soak up power while the car is parked to run the A/C while the car is driven.

edit: oops - Karik beat me to it.
 

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What 100 % Power means as a wattage measured with kWh meter

I was able to turn on the comfort heat, fan at 6, no auto features and full seat heaters and determine that when the vehicle is plugged into 240, no power usage registers on the kWh meter. But, when disconnected from charger, the kWh advances at 0.1 kWh per minutes for a total usage of 6 kW. This means that in 10 minutes, you will use 1 kWh, roughly equivalent to 4 miles of range. The car heats the same way when plugged in and running or unplugged and running BUT when remotely started and plugged in, the rate of heating is only about 1/3, suggesting some type of ECO mode is enforced during the remote start process.
 
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