I have only had this happen once and I had the Fan Blower a little over half way and the stereo on about 6. Additionally at the time I didn't realize that the Sun Screen was making the auto lights come on and I got that message ~20 minutes in.
Since then I try to remember to make sure the lights are off and do not use the blower for as long. I have yet to get that message again.
I usually am running on battery for ~50 minutes a day during the work week.