Solar Panel FAQ

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Thinking of switching to solar? Those shiny black panels come with lots of questions: everything from how much space they take up to how they affect your roof. And that can complicate your decision to take control of your energy choices, especially if you’re constantly feeling around in the dark.

We knew that homeowners had plenty of concerns about choosing a new solar energy system. So we decided to gather up the most common queries we heard and provide our readers solutions, all in one place. Here are your solar panel questions answered.


How do solar panels work anyway?

Solar panels consist of collections of solar cells—usually around 36, to be precise. The molecular makeup of those cells knocks electrons loose from the light particles when they’re hit by the sun. Those electrons are then funneled into wires and converted into usable electricity for your home.

Do solar panels affect home property values?

Yes. Studies performed by the Lawrence Berkeley National Laboratory showed that solar has a positive impact on home resale prices. In fact, it even reduces the length of time that properties spend on the market. The National Bureau of Economic Research found the same positive correlation between renewable energy systems and home values. Their data showed that solar adds an average $20,194 to property values. That means that many homeowners will totally recoup the cost of their initial investment.

Will solar panels harm my roof?

Actually, quite the opposite. Solar panels shade asphalt roofs from damaging UV rays. Meanwhile, the hard surface protects rooftops from wear and tear from storms. They may even keep the rooms directly below the panels cooler. And that means you’ll use less energy on AC.

Should I replace my roof before installing solar panels?

It depends. If your roof is older—over ten years or more—you should definitely think about replacing before you start. Most roofs only last around ten years, whereas solar panels are usually warrantied for 25 years or more. And replacing your roof after the panels are installed can add unnecessary costs to the project, since the roofers will have to remove the panels first to put in the new shingles. Most experts recommend that at the very least, you have your roof inspected before purchasing a solar energy system.

Does the slope of my roof affect my system’s productivity?

Yes—a lot. In fact, some installers think that if your roof slope is too flat, it could reduce your energy performance by as much as 10 percent. Many factors, like your home’s orientation, your location, and shading from trees, can have an effect on your solar panel production. To get a good feel for your home’s potential, check out a solar calculator, like Modernize’s ModSun calculator first.

How much roof space do I need for my solar panels?

The size of your system depends both on your home’s energy consumption and how much money you’d like to spend. However, the most commonly installed size measures around 65 inches by 39 inches, and weighs about 40 pounds.


How long does the installation take?

The installation is the easy part—usually installers say you should estimate around three days for the project. However, the process of applying for rebates through your energy provider can significantly increase the overall installation time. Usually, you need to apply for these projects and be approved before any construction can begin. And depending on how efficiently your provider processes applications, getting the paperwork in order could take months. However, your installer should guide you through the process, and provide an accurate timeline for your installation.

Are there size restrictions for solar energy systems?

Maybe—and particularly if you want to participate in a program with your energy provider to purchase or credit your account for excess energy you generate. For this reason, always start with your local electricity company and get the full details before you even begin. Your local installer should also be able to provide assistance here.

What can I do to ensure my panels work efficiently?

Improve, improve, improve. Efficiency upgrades throughout your home, like better insulation, air sealing, and more effective HVAC systems, are recommended, especially if you’re suffering from high energy bills. It won’t do you much good to start generating your own electricity if your home is an energy hog. It may even be useful to have a professional perform a home energy audit before you purchase your panels, so you can make the necessary adjustments to get your efficiency up before you invest in a solar energy system.

How can I find out more?

If you’re starting to seriously think about going solar, the next step is to speak directly with a knowledgeable solar representative who can get you the best information for your individual situation. That will help you get your project started as quickly as possible—and get you saving hundreds on your electricity bills!

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