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How Long Do Solar Panels Last at Peak Efficiency?
January 5, 2022 at 10:30 PM
Image of a worker installing solar panels on a roof answering the question how long do solar panels last.

One of the most common questions homeowners ask when they’re considering installing solar panels is, “How long do solar panels last?” It’s a serious consideration, given the expense of the panels and installation. If they lose significant charging efficiency after a few years, it may not be worth it to purchase and reinstall new panels, even for the environmental benefits.

Asking about the longevity of solar panels is an essential part of the due diligence when deciding to switch to solar. Whatever installation company you choose to work with should take the time to answer your questions, including how long do solar panels last. Here is the best information available about solar panel efficiency in California.

How fast do solar panels lose their efficiency?

The National Renewable Energy Laboratory (NREL) studied current PV panels and the degradation of efficiency over time. One of the central questions for the study was whether PV panels produce the same amount of electricity year after year.

The study found that median PV panel efficiency degrades 0.5 percent per year. While that may be hard to visualize, it essentially means that after 20 years, a panel will produce 90 percent the amount of electricity as it did during the first year.

Will my solar panels last longer, depending on where I live in California?

The NREL study found that in hot and dry climates, solar panel efficiency may drop faster than in cool and temperate climates. The efficiency may also decrease more for rooftop systems. Where you live in California could impact how long your solar panels last. Still, if you live in a hotter climate with more sun, you will generate more solar power with your rooftop system.

SolarSwitch customizes solar panel systems to every property to maximize their benefits and protect them against damage and excessive degradation.

What is the standard lifespan for solar panels?

Most manufacturers of multi crystalline-silicon PV provide 25-year warranties for their products. They estimate that after the 25-year point, the panels will produce approximately 80 percent of the electricity they did during the first year.

Solar panels don’t stop working after the warranty expires. You may find that you’re able to generate enough electricity to power your home for years, or even decades longer, depending on the climate where you live.

Image of palm trees in the sun answering the question how long do solar panels last.

Is it still worth it to install solar panels if they lose efficiency?

In a word, yes. It’s estimated that the energy savings solar arrays generate for residential properties will pay for themselves in around four years. That means at least two decades of free electric power before you’ll have to consider replacing your array.

SolarSwitch knows that installing solar on your roof is a big decision for a homeowner. That’s why we think of ourselves as a consultant first. We evaluate our clients’ properties and energy bills to customize a system that provides maximum benefits without high costs. We even repair and upgrade roofs to support the solar array.

SolarSwitch answers the question of how long do solar panels last and more during their initial consultation.

SolarSwitch is a custom solar panel company that works with homeowners to lower their energy costs and make their homes more energy-efficient and environmentally friendly. Our team works across California, helping residential property owners understand the complexities of solar power and how to maximize the benefits of solar energy for their homes. We know there are many options for solar panel installers available. That’s why we’re committed to going further for our clients, providing customized systems and exceptional customer service.

You’re not alone if you have questions about the benefits of solar power. We take time to explain the system and its operations and answer all your questions, including how long solar panels last.