Potential Battery Saver??

Hey yall! I've never posted on here before, but I've been looking into alternative ways to keep my windshield defogged while driving in the cold. I've been able to drive my little SparkEV long(ish) distances with precisely timed charges and slower driving on highways as the winter has begun to set in in my area, but one problem that I have been facing has been keeping my front windshield window defogged. I've thought about maybe getting a small car defogger "space heater" basically that would plug into my 12V power port, but I am not sure if running that will effect my battery life and ability to drive 40ish mile stretches on my way to work. Do you think that would affect my battery just as much as using the heating in the actual car? Or since it's drawing power from the 12V will it not effect the overall High Voltage battery that powers the driving range?? I'm just kind of looking for outside perspective who might have more experience in driving the spark than me. This is my first winter wanting to drive my spark longer distances (new job further away as compared to previous years), and I am just worried about not being able to make it to my regular chargers that I stop at on my way in to work each day.

Let me know your thoughts!

Check out some of the discussion here
https://www.mychevysparkev.com/threads/chinese-diesel-heater-mod.9556/

really quick, the windows are fogging up because the relative humidity at the panes is 100%. Heat will warm parts of the window up and increase the dew point, but you're battling a forest fire with a garden hose.

Defogging uses the AC compressor to make a cold spot in the car, the blower fan blows humid air across it to condense water on it and dehumidify the air, and then the heater warms the air back up and blows dry air over the windows to evaporate the fog.

Do you think that would affect my battery just as much as using the heating in the actual car? Or since it's drawing power from the 12V will it not effect the overall High Voltage battery that powers the driving range??

Click to expand...

The 350V battery keeps the 12V fully charged during drives with something called the 14V auxiliary power unit. In other words if you take 100W from 12V power, you're sourcing 100W from the high-voltage batteries.

the 12V sockets are rated under 250W. Say you used 200W for an hour, and your winter efficiency is 2.6 mi/kWh. Then you'll have lost half a mile of range in the hour you used it. Not very much. But your space heater won't heat your windows enough to keep them above dew point so you can drive. You'll need at least 4 or 5 of them and position them all around strategically. It's a nightmare just thinking about it.

I would use the built in defogger. If you don't need the heat just turn it on and off as you need it. You could also try getting a 12V dehumidifier to dry out the car, but outside of preconditioning the car, I feel it would simply do a subpar job.