A solar PV system is a long-term asset. While most modules carry a 25-year performance warranty, degradation is a key consideration for asset planning and ROI analysis.
Typical manufacturer guarantees include:
- 90% output performance through year 10
- 80% through year 25
Why Solar Panels Lose Power Over Time
All solar panels slowly lose their ability to generate electricity as they age. This happens because weather and outdoor conditions—like heat, rain, and wind—can gradually wear down the panels.
One common reason is the formation of tiny cracks (called microcracks) in the silicon cells inside the panel. These cracks block some of the electricity from flowing through, which means less power gets to your home or business. Other issues can include discoloration or poor bonding in the panel’s parts.
Different factors impact Solar Power Plant and Panel differently, but manufacturers are always working to reduce how fast this wear and tear happens. Most panels are designed to lose power at a slow and steady rate, and warranties are there to protect your investment.
Reasons Behind the Degradation of PV Panels
Solar panels are tough, but over time, they slowly lose some of their power. One of the biggest reasons? Weather—which, of course, we can’t control.
For example:
Temperature changes cause the panels to expand and shrink, which can lead to tiny cracks (called microcracks) inside the panel. These cracks affect how well electricity can flow.
Strong winds can flex the panels slightly, which is called mechanical loading. A well-installed system using good-quality panels can handle this without major issues.
Other weather conditions like extreme heat, cold, snow, humidity, and ice can also slowly wear down a panel over many years.
You might wonder, “Can sunlight itself cause damage?” The answer is—yes, but only a little. Right after installation, when the panel first gets sunlight, it can lose about 1–3% of its performance. This is normal and is called light-induced degradation (LID). After that, the panel wears down very slowly.
How Fast Do Solar Panels Wear Out?
On average, solar panel lifespan lose about 1% of their power per year. That means they slowly make less electricity as they age. Most solar panel warranties promise:
- 90% of their original power output for the first 10 years
- 80% by the 25th or 30th year
But here’s the good news: newer panels degrade more slowly.
A study by the National Renewable Energy Laboratory (NREL) looked at nearly 2,000 solar systems around the world and found that modern monocrystalline panels (made after 2000) degrade at just 0.4% per year on average.
Most panels lose a small amount of power right after installation—this is called light-induced degradation (LID). After that, the performance drop slows down and stays steady for many years.
What Happens to Solar Panels After 30 Years?
After 30 years, solar panels don’t just stop working—they just slow down a bit. Most panels are called “old” when they produce less than 80% of what they could when they were brand new. But they still make electricity!
Think of it like a phone battery. It doesn’t hold a charge like it used to, but it still works. Some people even get free electricity for 25 years or more because they paid off the cost early. So older solar panels can still help you save money, even if they aren’t as powerful as before.
