How Long Do Solar Panels Last?

Solar panels are another significant investment in your home. To reduce electricity bills, solar is the best option. So, people ask, “How long do solar panels last?” 

This guide answers that question in plain language. In addition, it explains the solar panel lifespan, degradation, replacement, and warranty in simple steps. Also, it gives practical tips. Let’s go and explore all the things that matter before you install a solar panel.

Average Lifespan of Solar Panels

25 to 30 years is the last time for solar panels. After that, they still work. However, they make less power than when they were new. In short, the 25–30 year mark is the usual point when homeowners think about replacing panels.

Once a solar panel reaches 25 years, its electricity production often declines gradually over time – typically still meeting between 80% to 90% of its original power output after 25 years! 

Solar cells slowly lose performance over time. Therefore, “lifespan” generally refers to useful life. That means when your panel produces enough power to meet your needs at an acceptable cost-efficiency. We’ve heard that some solar panels can still function after 30 years. But if you replace them with modern panels after thirty years, it will work better for you.

Factors Affecting the Longevity of Solar Systems

Several factors affect the solar panel lifespan. Here are the key ones. Use these points to check your own system.

• Panel Quality and Type

High-grade panels last longer than their cheaper counterparts and typically outperform polycrystalline ones in terms of performance. Monocrystalline panels were found to provide superior results. New N-type panels are even stronger and lose less power each year. Choosing good panels at the start helps you enjoy steady energy and a longer system lifespan.

• Installation Quality

Poor installation can shorten life. For example, bad wiring or loose mounts can cause damage. Therefore, hire a trusted installer. Also, ask about workmanship warranties.

• Local Climate and Weather

Heat, humidity, hail, snow, and salty sea air can speed wear. For instance, very hot roofs can raise degradation. Thus, systems in harsh climates may lose capacity faster.

• Maintenance and Cleaning

Panels need little upkeep. Yet, simple tasks help a lot. For example, keep panels clean from dust and leaves. Also, look for evident bird droppings and check for cracks. A little care often extends life.

• System Components and Inverter Life

Remember, the inverter usually fails before the panels. Many inverters last 10–15 years. So, you may replace the inverter while keeping the panels. Additionally, wiring and mounts should be inspected periodically.

• Manufacturing Defects and Material Failures

Sometimes panels have factory defects. In that case, the solar warranty can help. Check the product and performance warranties before buying. Inspection is essential because it is such a significant investment.

Solar Panel Degradation Rate

Panels degrade slowly. The standard range is about 0.3% to 0.8% per year. Many studies find a median of around 0.5% per year. That means after 20 years, a panel may still produce about 90% of its first-year power.

• To Show This Simply

If a panel loses 0.5% per year, then after 25 years it keeps roughly 88–90% of output. If a panel loses 0.8% per year, then after 25 years it keeps about 80–83% of its output. Thus, small yearly losses add up slowly. Also, note that premium panels sometimes advertise lower loss rates, like 0.25%–0.4% per year. These panels keep more power after 25 years.

• Why Panels Degrade

There are several causes. First, exposure to sunlight causes tiny chemical changes inside the cells. Second, thermal cycling (day/night heat changes) causes stress. Third, moisture or salt can corrode parts. Fourth, micro-cracks can form from wind or hail. All of this leads to a gradual loss of output.

How Researchers Measure Degradation

Researchers use power tests over time to determine solar panel degradation. They use electrical curves and real-world data. For instance, we studied many systems and found that degradation is usually small and steady, but it varies by climate and mounting.

Warranty & Replacement of Solar Systems

Warranties are key. They tell you what the maker promises. There are three main warranties to look for.

• Performance Warranty

This is the most important one. It guarantees a minimum power level at a future date. Most performance warranties promise about 80–90% output after 25 years. In many cases, the standard is 80–84% at year 25. Some top brands promise more.

• Product Warranty (materials)

It covers defects in the panels themselves. It often lasts 10 to 25 years. Many makers give 10–12 years. Some offer 25 years. Check the fine print.

• Workmanship Warranty (installation)

It covers the installation process of the system. It often comes from the installer. Lengths vary. Standard terms are 5–10 years. Always ask for a written workmanship warranty.

How To Use a Warranty

If your panels underperform, first contact the installer. Next, the installer may test the system. Then you may claim under the manufacturer’s warranty if tests show worse output than promised. 

Keep records of your system’s performance and maintenance. Also, verify who pays for shipping and testing. Some warranties have fees or limits.

When To Replace Panels

You may replace a panel or the whole system for several reasons:

• Production drops a lot.
• Panels have visible damage.
• Repairs cost too much.
• Better technology offers significant gains.

For many homeowners, solar panel replacement is a financial choice. In short, when the cost to keep the old system is more than the benefit, consider replacement.

For many homeowners, replacement is a financial choice. In short, when the cost to keep the old system is more than the benefit, consider replacement.

When & How to Do Solar Panel Replacement

Solar system replacement can be simple, but it needs plans. Here are clear steps.

• Check Performance Data

First, review your system’s production over the course of months and years. If output drops sharply, it could mean a problem. Also, compare the expected production for your area. If real output is much lower, investigate.

• Inspect Panels and Hardware.

Look for cracks, discoloration, or loose frames. Also, check wiring and junction boxes. A visible problem often needs repair or replacement.

• Test Individual Panels

A solar technician can test each panel. Simple tests show if a panel is failing. Also, technicians test the string performance and the inverter function.

• Consider Partial Replacement

Often, you can replace only the broken panels. This is cheaper. Yet, mixing ancient panels with new ones can reduce system balance or appearance.

• Evaluate New Options

If panels are old, replacing the whole system may pay off. New panels are more efficient. Additionally, you may receive better warranties. Also, new inverters and battery options can add value.

• Recycling and Disposal

Finally, don’t just throw away panels. There are recycling programs. Recycling recovers glass, metal, and silicon. Always ask your installer about the recycling options available in your local area. It keeps panels out of landfills while helping recover valuable materials. So, it can be a good option.

Now, let’s move to the tips to increase the solar panel lifespan.

Tips to Extend Solar Panel Life

Small actions help a lot. Here are practical tips.

• Clean panels gently. Do it a few times a year.
• Trim trees that shade panels. Shade speeds loss.
• Inspect panels after storms. Look for cracks.
• Fix minor issues early. Wiring faults can worsen.
• Keep an eye on the inverter lights. An inverter fault can cut the output.
• Ask for performance reports each year. That shows trends.

Conclusion

Now you know how long solar panels last. Even after 25 years have passed, solar panels will still work, but at reduced output. On average, degradation rates of about 0.5% each year mean you should still get plenty of energy over this timeframe. Warranties typically cover at least 80-90% performance after 25 years, providing you with peace of mind.

For optimal results, partner with a reputable and established company. At NEDES.us, we offer high-quality solar systems, expert guidance, and reliable service so your panels last as promised and save you money year after year.

FAQ

Do animals or birds damage solar panels?

Yes, sometimes birds nest under panels. Their droppings can block sunlight and reduce power. Small animals may chew wires, and mesh barriers are practical tools to deter these animals. Perform regular checks to avoid these damages and clean it gently.

What does a 25-year performance warranty mean?

It means the manufacturer promises a minimum power output after 25 years. Often this is about 80%–90% of the original production. If panels produce less than that, you can make a claim.

How can I identify whether my solar system needs repair?

If your energy bills suddenly decrease, that may indicate the system is underperforming. Check the inverter lights for errors. Cracks or loose wires are also warning signs. Call a solar technician if you notice these issues.