Switching to solar power can help you save money on your electric bills and reduce your carbon footprint, but figuring out the right number of solar panels for your home can be tricky. Several factors come into play when calculating the right amount of solar panels for your needs. Keep reading to learn how to figure out the right number of panels for your home’s solar power system.

Assess Your Energy Consumption

The first step in calculating how many solar panels you need is to evaluate your energy usage. Check your electricity bill for your average monthly usage, which is usually measured in kilowatt-hours (kWh). To get a more accurate picture, it’s best to look at your usage over the past year to account for seasonal fluctuations, rather than just the last month or two. Most households in the U.S. consume around 900 to 1,000 kWh per month. Multiply your monthly consumption by 12 to estimate your annual energy needs.

Consider Solar Panel Output

Solar panels are rated based on the amount of electricity they can generate in ideal conditions, and is typically measured in watts. Standard solar panels today range from 300 to 400 watts per panel. This rating refers to the panel’s output in peak sunlight. To convert the panel's wattage to kilowatt-hours, multiply its wattage by the average number of sunlight hours your location receives per day, then divide by 1,000. For example, a 350-watt panel in an area with 5 peak sunlight hours per day would generate about 1.75 kWh per day.

Estimate the Number of Panels Required

Now that you know your total energy consumption and each panel's output, you’re ready to calculate the number of panels needed. Divide your total annual energy consumption by the estimated annual production of 1 solar panel. For example, if you use 12,000 kWh annually and a single solar panel generates 600 kWh annually, you would need 20 panels (12,000 ÷ 600 = 20).

Consider Your Available Roof Space

Roof space and the way the sunlight hits your roof can also play a key role in determining how many solar panels you can install. Each panel takes up roughly 17 to 21 square feet. You'll need to ensure your roof has sufficient space and is positioned to capture adequate sunlight.

It’s important to keep in mind that different types of panels have different efficiency levels. So, you’ll need to recalculate the number of panels you need on your roof for each panel type you’re considering. If you would like personalized support and help calculating the right number of panels to connect to your Fronius hybrid inverter, speak to a solar expert.