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I pretty much always have my stereo and daytime running lights on and the AC off. Sometimes when I'm at a stop light it shows .5kWh usage and other times it shows 0. Any ideas as to why?
 

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all the accessories run off the 12 V battery bus, some you can turn off but some are always on (e.g. the various computers and control modules that make the car work). The system will draw current From the HV traction battery to maintain the 12V bus at the correct level, buffered to some extent by the 12V battery.

incidentally, it's displaying .5 kW, a rate of energy use-- .5kWh is a quantity of energy
 

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I pretty much always have my stereo and daytime running lights on and the AC off. Sometimes when I'm at a stop light it shows .5kWh usage and other times it shows 0. Any ideas as to why?
Volt uses energy even when stopped with everything shut off just for being "on". Those computers and onboard systems don't run on just happiness. ;)
 

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My ELR can go up to 5kW when stopped and the A/C on in 107F weather. Don't care. I want to be colder than 107.
 

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Volt uses energy even when stopped with everything shut off just for being "on". Those computers and onboard systems don't run on just happiness. ;)
You lie you heathen... of COURSE the Volt runs on rainbow sprinkles and happiness! (lol)
 

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Most of the time, that power consumption display only changes in 1 kw increments, except when it is less than 1 kw. When the display says 0.5 kw, you may be using somewhere between 250 and 750 watts and the display rounds it to 500 watts (0.5 kw).

That really isn't a lot of power. A laptop could use 50 watts, a fan circulating air in the cabin could use 20 watts, your music could be consuming 5 watts, etc...
 

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I always like to point out that the average hair dryer is 1 to 1.5 kW of draw just to give people a physical and understandable comparison.
 

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Most of the time, that power consumption display only changes in 1 kw increments, except when it is less than 1 kw. When the display says 0.5 kw, you may be using somewhere between 250 and 750 watts and the display rounds it to 500 watts (0.5 kw).

That really isn't a lot of power. A laptop could use 50 watts, a fan circulating air in the cabin could use 20 watts, your music could be consuming 5 watts, etc...
I've measured the idle power usage in my '12 via an OBDII adapter and the Mygreenvolt app.....idle usage is about 400 watts with everything off. I suspect Gen 2 is very similar.
 

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I think the average human burns at a rate of about 80 to 100 watts resting. A trained cyclist can produce 400 watts continuously.

As stated, 500 to 1000 watts is reasonable idle (parasitic) draw for the car. It is higher than your average computer, but there are all sorts of systems, antilock brakes, airbags, traction control, vacuum pump for brake assist, steering assist motor, two high brightness LCD displays, radio (these can be high power), seat heaters, AC, Heater, lighting, etc. The electrical heater can draw over 7000 watts, and the AC maybe 2000 watts (haven't measured it). Those are the two biggest consumers.
 

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Good to know, thanks. I don't use AC as much as heat, but would explain why my battery is low after my wife drives (she often sits in the car for an extended period with the AC blasting) ;)
 

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My 1981 Comutacar EV uses 30-60 watts "idling" and it doesn't have a deepcycle 12v, only a DCDC.

I think chevy could do better if they wanted.
 

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rmay, I don't mean to be negative, but your comment comparing a Comuta-Car to a Volt just made me laugh out loud. For those of you who don't know, a Comuta-Car was a little 2 seat NEV that had a 6 hp motor at best. It was less than 8' long and weighed in right at 1300 pounds. It had the rudimentary of computers, if it had them at all. Sensors, power steering and it couldn't quite get to 40 mph.
Vs. a Volt.
GM could always do better, but the Volt is a pretty impressive bit of kit.

https://en.wikipedia.org/wiki/Citicar


My 1981 Comutacar EV uses 30-60 watts "idling" and it doesn't have a deepcycle 12v, only a DCDC.

I think chevy could do better if they wanted.
 

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My 1981 Comutacar EV uses 30-60 watts "idling" and it doesn't have a deepcycle 12v, only a DCDC.

I think chevy could do better if they wanted.
Does the Comutacar have:

GPS Navigation
Bose Stereo
heated seats
6-8 airbags
OnStar
TMS
Bluetooth
multiple computers to keep it all running smoothly?

Sounds like your Comutacar EV could do better if they wanted.

I just looked at the Wiki link and now I am LOL.
 

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The system isn't precise enough to tell you the exact amount.
0.5 means more than zero, up to 1kW.
Idle is anywhere from 200-500W depending on accessories and systems that are on. You can see a more precise amount with OBD, but even that is limited to ~128W increments, IIRC.
 

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When I head home after work when it's 118 degrees outside, my parked power usage reads 2-3 kWh. My AC is blasting away trying to keep me alive. :D
 
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