When considering a switch to solar energy, one of the most common questions homeowners ask is: “How many panels will I need?” The answer depends on a range of factors, from how solar panels work to your household’s specific energy usage.
In this post, we’ll break down the basics of solar panel operation and guide you through the steps to estimate how many panels you might need for your system.
How Solar Panels Work
Solar panels convert sunlight into electricity using photovoltaic cells. When sunlight hits these cells, it excites electrons, creating a flow of direct current electricity. This DC power is then converted into alternating current (AC), the type of electricity used in most homes, by an inverter. The electricity generated can be used immediately, stored in a battery for later use, or sent back to the grid if your system is connected to one.
The power output of a solar panel is measured in watts (W), and residential panels typically range between 350 and 450 watts per panel. The amount of electricity a panel produces depends on factors like its efficiency, placement angle, direction it faces, and the amount of sunlight (measured in peak sun hours) it receives per day.
Estimating Your Energy Needs
To determine how many panels you’ll need, the first step is to understand your energy consumption. Check your electric bills to find your average monthly electricity usage, measured in kilowatt-hours (kWh). In the U.S., the average household uses about 900–1,000 kWh per month, but this varies widely depending on the size of the home, climate, and lifestyle.
For instance, if you use an EV or a plug-in hybrid car, you might need more solar panels to handle the higher load. (Even if you never have to stop at a gas station!)
Once you know your monthly or annual usage, you can calculate the total power your solar system needs to generate. For example, if your home uses 12,000 kWh per year (or 1,000 kWh per month), you’ll need a system that can produce about 33 kWh per day. You can figure this out by dividing your monthly kWh consumption by the number of days in the month!
You can take this even further by finding the peak sun hours of your location and estimating how much energy each panel will provide on a day to day basis. We can help you with that end of the equation.
Determining the Number of Panels
Next, once you’ve got an idea of how much energy is required on a daily basis, and how much energy each panel provides, you can quickly determine how many panels you’ll need.
Unfortunately, different panels, locations, and homes will generate different amounts of energy, so you’ll want to work closely with our team to get accurate results. Factors like roof space, shading, panel orientation, panel efficiency, and your utility’s net metering policies all influence how much solar you’ll need and how effective it will be.
Our team of Home Performance Experts has served the I-5 corridor from Blaine to Marysville, Oak Harbor to Concrete, and the San Juan Islands since 1972 with a mission of Improving Lives™. We look forward to serving you too! Contact Barron Solar Energy Services today for solar panel setup.