“and are careful about our use of electricity...”
There’s “careful” and there’s “careful.” A solar system should provide all the juice you need for a night’s camping and fully recharge the batteries the next day. Did you do an energy survey? Once completed, are your battery amp hours at least double that? Preferably 2.5 to 3. Do you have at least solar panels providing 1 watt per battery amp hour? Is your controller and your wiring adequate? Using battery lanterns and no stereo or TV stinks!
Tell us in detail what batteries you have.