The duration a solar battery can power a house depends directly on the usable storage capacity of the battery bank and the household's immediate electrical load. A standard 13.5kWh battery typically sustains essential nighttime loads—such as refrigerators, lighting, internet routers, and medical devices—for roughly 12 to 24 hours, whereas running heavy high-draw appliances like central air conditioning or electric ovens will deplete the same storage capacity within a few hours.