My only experience w/battery xma lites was a 10 lite set for a door wreath that would be on 5-6 hr a night . A set of batteries lasted at least 2mo. I use elcectric xmas lites in my coop and its enough lite for the chickens to go in at nite and wakes them up at six in the morn. There are batteries at Lowes that u can plug into , u just need to ask someone.