Chevy Bolt EV Forum banner

1 - 18 of 18 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter #1
Can we predict how expensive it would be to the battery to run the AC on low for 6 hours? Will there be any risk to doing this?
 

·
Registered
Joined
·
428 Posts
Why would you want to do this?

I don't think that we can figure this out at the moment. Not enough info by far.
 

·
Registered
Joined
·
428 Posts
Perhaps because it is an electric car, the battery will be better able to handle idling for a long while.
 

·
Registered
Joined
·
263 Posts
But if you intend to drive after idling for a long time, you may not have enough electricity to get to where you need or to the closest recharge station. I don't think charging stations are all that common.
 

·
Registered
Joined
·
639 Posts
Tesla is Tesla, they'll always be in the news and stand out when it comes to things like this. Tesla has its own reasons and motivations for doing this but fact is there's space for a lot of other companies to get in and there have been many. Just think of all the different gas stations out there.
 

·
Registered
Joined
·
1,031 Posts
I doubt there's going to be any risk in doing this once your in a good location in terms of charging and how far you need to go but I really can't see anyone doing this.. More of a general question because I'm inquisitive but, are you planning on being in the situation where you need the car to be sitting with the AC on for 6 hours...?
 

·
Registered
Joined
·
22 Posts
Can we predict how expensive it would be to the battery to run the AC on low for 6 hours? Will there be any risk to doing this?
Based on what our Spark EV reports (either 0 or 1 kW power drain when sitting still with AC on), the AC compressor and cabin air fan uses less than 1kW. So, 6 hours of AC with the car doing nothing else would be less than 6 kWh, or <10% of the battery. Of course, it's going to depend upon the set temperature and how hot it is outside, whether the car is in the sun or not, etc... exactly how much energy it ends up taking.

Heat is a bit more expensive: temperature differentials can be large and with resistive heat you are about 1/3 as efficient as the AC heat pump. It remains to be seen how well the Bolt scavenges heat from the battery and motor cooling systems, as has been reported, but that won't help if the car is just sitting still.
 

·
Registered
Joined
·
118 Posts
Charging Stations

Because Tesla is a brand with privatized stations that exclude the majority of EV users (unbranded), all other charging stations are for the regular folks and are very generic.

I have heard far more about Tesla charging stations than any other brands.
 

·
Registered
Joined
·
172 Posts
EVs don't "idle" in the usual sense. The drive system isn't active if you sit there just running the HVAC. The only real obstacle to doing this is you would undoubtedly have to remember to have the car in "Ready" mode (or just call it idling, if you like) to keep the accessory battery fully charged. Maybe GM will fix this by making sure the car charges the accessory system fully in "Acc" mode, but so far the Prius and Leaf don't do that at all well - Acc mode shouldn't be used for more than a minute or two, if at all.
 

·
Registered
Joined
·
22 Posts
EVs don't "idle" in the usual sense. The drive system isn't active if you sit there just running the HVAC. The only real obstacle to doing this is you would undoubtedly have to remember to have the car in "Ready" mode (or just call it idling, if you like) to keep the accessory battery fully charged. Maybe GM will fix this by making sure the car charges the accessory system fully in "Acc" mode, but so far the Prius and Leaf don't do that at all well - Acc mode shouldn't be used for more than a minute or two, if at all.
Not that you're wrong, but the OP didn't say anything about "idling" or the mode he wanted to have the car in, so I'm not sure how this is relevant. Clearly you can have the car sitting there, powered up and with the AC on as long as you want, as is the case for our Spark. Even though the car is "powered up" it's really not using any power for anything but the AC: lights, dash, etc. use <<1 kW.
 

·
Registered
Joined
·
172 Posts
The OP presumably named the thread, right? Anyway, my point is that whether or not you can do this may depend on what mode the car is in. Hopefully GM has corrected the problems with Accessory mode that Toyota and Nissan have created.
 

·
Super Moderator
Joined
·
787 Posts
The OP presumably named the thread, right? Anyway, my point is that whether or not you can do this may depend on what mode the car is in. Hopefully GM has corrected the problems with Accessory mode that Toyota and Nissan have created.
This isn't a problem that is specific to EVs or hybrids. Any car left in Accessory mode with things like the AC system on, or even just the radio, or headlights, runs the risk of running down the 12V battery. In the case of the Prius, when you are in Accessory mode, the high-voltage battery is disconnected from the system, much like having the engine off in a normal car.

I do agree that you shouldn't leave the vehicle in Accessory mode for too long, but it certainly can handle 5 or 10 minutes of it without harm to the 12V battery, but don't leave the AC system on while in this mode.
 

·
Registered
Joined
·
22 Posts
The OP presumably named the thread, right? Anyway, my point is that whether or not you can do this may depend on what mode the car is in. Hopefully GM has corrected the problems with Accessory mode that Toyota and Nissan have created.
The OP did more than name the thread, he wrote a post, and neither says anything about an accessory mode, which simply doesn't exist on these cars. There is no "accessory mode" in our Spark EV, and according to the manual, the Bolt is exactly the same:

https://my.chevrolet.com/content/dam/gmownercenter/gmna/dynamic/manuals/2017/Chevrolet/BOLT EV/Owner's Manual.pdf

Page 203, which reads exactly as it does for our Spark, says the only situation in which there is accessory power in the Spark is for the first ten minutes after powering the car off AND before you open a door. During that time the audio system works, the windows can be operated, and the power outlets (e.g. USB) still deliver power. That's it.

So, if you want to run the AC, the car will be on, and in that case the 12V lead acid battery is irrelevant.
 

·
Registered
Joined
·
172 Posts
Not that you're wrong, but the OP didn't say anything about "idling" or the mode he wanted to have the car in, so I'm not sure how this is relevant.
I was responding to the "idling" part, not knowing that they have apparently eliminated Accessory mode for GM EVs. As you can see (?), the word "idle" is right in the thread title. Let's not turn this forum into Usenet, eh? I'm glad that running the A/C with the car sitting still will be easy and foolproof.
 

·
Super Moderator
Joined
·
787 Posts
You can also put the car in "Service" mode (page 202 in the manual), which makes the displays and the audio system functional, but the car can't be driven. Sounds a lot like Accessory mode in a traditional car. Says not to leave it in this mode for very long or the car may not not start. In order to put the car in this mode as you have to have your foot OFF of the brake pedal and press the Power button for 5 seconds, so it's pretty hard to accidentally do it.
 

·
Registered
Joined
·
22 Posts
I was responding to the "idling" part, not knowing that they have apparently eliminated Accessory mode for GM EVs. As you can see (?), the word "idle" is right in the thread title. Let's not turn this forum into Usenet, eh? I'm glad that running the A/C with the car sitting still will be easy and foolproof.
OK, glad I could help you understand how these cars work. I believe the information the OP asked for is back in post #9 . :)
 
1 - 18 of 18 Posts
Top