Solar 101: How Many Solar Panels Can I Fit On My Roof?

Solar 101: How Many Solar Panels Can I Fit On My Roof?


If humans were to harness all of the solar energy that hits the Earth for an hour, it would be enough to fulfill the world’s energy needs for an entire year. We can’t capture or store that amount yet, but we’re slowly getting there — homeowners are helping. By installing solar panels on their roofs, they’re aiding the transition and saving money on their energy bills, capturing more of the sun’s rays, and creating a brighter future. You may wonder, “How many solar panels can I fit on my roof?” After all, maximizing power generation is critical if we ever want to harness all of the sun’s energy.

Calculating the number of solar panels you can fit is relatively simple, though other factors can affect how a solar system works on your roof.

How Many Solar Panels Can I Fit on My Roof?

Solar panels are usually 3 feet by 5 feet, or 15 square feet total. With that panel size, you’ll want to divide the available square footage of your roof by 15, which will tell you the number of solar panels you could fit on your roof. For example, if you have 300 square feet of available space, you could install roughly 20 solar panels (300/15 = 20).

Of course, you’ll need to measure the amount of space that’s available for an accurate reading of how much space you have. It’s critical to wear proper safety equipment if you plan to go on top of your roof — any misstep, inclement weather conditions, or other factors could lead to a catastrophic fall without the proper care. Using an online tool is the simplest way to check how many solar panels your roof can fit. For example, Google Project Sunroof will estimate the space available for solar panels using 3D rendering techniques and other valuable information about solar installation near you.

You should work with certified solar installers for the most accurate estimates. They’ll have specialists that can create personalized solar systems based on satellite imagery. That’s less work for you while ensuring you have a reliable system design. If you’re looking for a free solar system design, Purelight Power offers them to homeowners with qualified roofs. Take our 30-second survey to see if you’re eligible.

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How Much Solar Energy Can My Roof Generate?

A single panel in a solar system will produce about 2 kWh per day (40 kWh a day in our 20-panel example), but there are a lot of variables. The panel’s size, efficiency, and orientation are all factors in how much energy a solar installation on a roof can generate, not to mention the overall size of the system you’re installing. Notably, the critical factor isn’t necessarily how much solar energy your roof can support generating but whether or not it can successfully produce enough energy to meet your needs consistently. If you’re using 900 kWh monthly, you want a system that can offset most of that.

Solar panel technology has become more efficient and affordable over the last decade, so the baseline for energy production has steadily increased. Solar panels aren’t the only factor in energy production, though. For example, If your roof is in the shade of a tree, it will hinder your energy generation capabilities. Keep those kinds of factors in mind as you go through the system design process.

Can I Get More Solar Power From My Roof?

If you’ve found that your system is regularly under-producing, a solar installation on a roof can be modified to generate more power. However, these modifications can be expensive and labor-intensive, and the process will vary depending on your situation. You’ll likely need additional permits and have to work around your remaining roof space. Because of the logistical issues that go hand-in-hand with modifying a solar installation, it’s best to ensure that the process is completed correctly the first time you install solar on a roof.

The ideal option is to find a local solar company to perform your initial installation, as you’ll have better odds of fulfilling your needs from the onset. Be sure to work with a reputable company, as sloppy craftsmanship can significantly impact your system’s performance. A high-caliber professional will back their work with warranties and guarantees, so you’ll have peace of mind that your solar system is high quality.

Where Can I Find a Solar Installer for My Roof?

Depending on where you live, you may have dozens of options for a solar company near you. Each one has pros and cons, so it’s essential to research their values and skill. You may be locked into a solar company once they’ve installed panels on your house, as many companies won’t touch another’s previous work due to the possibility of encountering poor wiring or craftsmanship. Therefore, it’s critical to read reviews, receive multiple quotes, and chat with others who have had solar panels installed.

Start by checking out a company’s reputation online. You’ll learn a lot about what they’re good (and bad) at based on customer reviews on their business profiles. You can also check their social media accounts to see their values. From there, you can ask friends and neighbors with solar panels about their experience. Call a few companies, ask their solar installers questions, and get quotes. Make sure the company values transparency and communication — you should never feel like a second priority.

At Purelight Power, we take the time to ensure your questions are answered and that you have complete faith in the installation process. We understand how important your home is to you, and we respect that connection. We offer a 25-year performance guarantee and a 10-year workmanship guarantee so you can have confidence in your solar system. If you want to know how many solar panels you can fit on your roof, take our 30-second survey and we’ll show you.

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