On a cold (mid 40s) rainy night, my 500e went from 70% charged to 1% on a 34 mile round trip to take the grandkids home. Headlights and wipers on the whole way, heat on, but not the seat warmers. And the radio was on. Had to switch on the front defroster frequently, but not the rear. Maybe I need to look into LED headlamps? I'm beginning to think there's a level 2 charger in my future. If I had one, I'd almost never have to leave the house with less than a 100% charge.