How Long Do Solar Panels Last?

June 7, 2024
5 min read
a hand repairing solar panel mounting bracket

If you’re planning to invest in solar energy for your home or commercial business, the biggest question on your mind is likely how long your investment will last. After all, solar panel installation is a costly endeavor: You want to make sure the solar panels you choose will be strong and reliable for years to come.

You’ll be happy to learn that while the industry standard for a solar panel’s productive life span is between 25 and 30 years, panels don’t die after surpassing this time frame. Instead, their output decreases significantly below the manufacturer’s projected output levels.

This is why homeowners need to understand panel degradation rates and industry projections so they can get the most out of their solar panel investment.

What Is Solar Panel Degradation Rate & Why Does It Matter?

Put simply, the solar panel degradation rate is the rate at which solar panels decrease their output year over year. According to a 2012 study by the National Renewable Energy Laboratory (NREL), the average solar panel loses about 0.8% output annually.

However, degradation rates are specific to the types of solar panels you install. For instance, premium panel manufacturers like SunPower boast a degradation rate of just 0.3%.

It’s also important to note that 10 years have passed since this study was published, and a lot has changed in the solar power industry since then. Today, more efficient technologies have dominated the marketplace, with many newer panels offering just a 0.5% degradation rate or better.

What Does Degradation Rate Actually Mean For Solar Panels?

Let’s take the earlier example of a solar panel system with a 0.8% degradation rate: That means in two years, your solar panels will operate at 99.2% of their original output.

Using this same rate of decline, at the end of your solar panels’ 25-year useful life span, they will operate at just 82.5% of their original output levels. This rate can leave you with a significant difference in energy output at the end of the average 25-year life span, as illustrated in the table below:

Panel Degradation Rate Panel Output After 25 Years
0.8% 82.5%
0.5% 87.5%

How Long Do Solar Panels Usually Last?

Solar panels typically last 25–30 years. However, it’s important to note that they don’t stop producing electricity at this point. Rather, their energy production levels decline below the manufacturer’s projected levels.

Are There Ways To Make Solar Panels Last Longer?

Solar panels are incredibly durable and require little to no maintenance; however, that doesn’t mean giving them a little extra love won’t go a long way. The best way to keep your solar panels at peak efficiency is by having your installer provide a routine solar panel inspection to identify potential issues such as loose racking, exposed wires, and other system defects.

It’s also important to keep your panels free of any debris. Your solar panel installation specialist should ensure that no large trees could cast shade or drop branches onto your panels.

Avoiding physical damage to your solar panels is critical if you want them to last beyond the average life span. Consider investing in solar panel critter guards to keep pests from nesting under your panels and causing wire damage.

TENCO SOLAR For Long-Lasting, Reliable Solar Power!

At TENCO SOLAR, our team has more than 20 years of experience serving Southern California’s solar energy needs. Our installation experts work hard to ensure your solar panels are set up for decades of reliable use, clearing away potential hazards that could cause your system to degrade or fail prematurely.

Whether you’re seeking solar panel installation or inspection services, our team can help ensure that you’re getting the most out of your solar power investment.

Get a solar panel installation quote from our team by calling  (888) 507-6937 today!

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With over two decades of expertise in designing and installing solar systems for residential and commercial properties across California, TENCO SOLAR is the perfect partner for your upcoming solar project.