How Many Solar Panels Does It Take To Run an Average Household? An average U. household uses about 10,500 kWh per year. Depending on your panel wattage and local sunlight hours, you'll likely need 20 to 30 panels. Most homes need 16-23 solar panels to ditch their electric bill. Here's how to figure out your magic number. Future-Proofing Saves Money: Adding panels later costs significantly more due. So, the number of panels you need to power a house varies based on three main factors: In this article, we'll show you how to manually calculate how many panels you'll need to power your home. It comes down to the amount of energy your household consumes, which in turn depends on things like the number of people living in your home, the number of appliances you have and how often.