You do not need to invest $100's to $1,000's of dollars in your current setup for a few nights. I live in Alaska and get by with a single group 24 battery over a weekend (lows in the upper 40's-50's) of camping unless you need to keep the camper very warm. I keep mine at 66-68 and the battery holds up just fine. Some day I'll have two batteries, but for now it's not really needed for basic lighting and enough heat to knock the chill off. I use my generator when I want to use an electric coffee maker or the microwave, but it's not needed for a weekend of camping.