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Is it true that solar panels lose efficiency over time?

Yes, it's true—but the decline is gradual and predictable, not sudden or severe.

The Reality of Solar Panel Degradation

Solar panels do lose efficiency over time. The typical rate is about half a percent per year. That means after 25 years of operation, your system is still generating more than 80 percent of its original output.

This isn't a flaw or a surprise. It's a natural part of how the technology works. Manufacturers know this happens, which is why they back their panels with warranties that often stretch 25 years or longer.

Why This Matters for San Diego Homeowners

If you're considering solar for your San Diego home, understanding degradation helps you make a realistic decision. You're not buying a system that will magically produce power forever at peak levels. You're buying one that will reliably generate electricity—with a slow, steady decline—for decades.

The math works out favorably. Even after a quarter-century, you're still getting strong performance. For many homeowners, that means decades of meaningful savings on electricity bills.

What Causes the Decline?

Panel degradation happens due to exposure to sun, heat, humidity, and weathering. It's not something you can prevent, and it's not caused by poor installation or maintenance. It's simply the physics of the materials.

Different panels degrade at different rates. Some premium panels degrade slightly slower, but the difference is modest. What matters more is that you choose a reputable installer and keep your system maintained.

Keep Your System Running Strong

While some degradation is inevitable, you can keep your panels operating near their rated efficiency:

  • **Clean them occasionally.** San Diego's dust and salt air can accumulate on panels. A periodic cleaning helps light reach the cells.
  • **Get regular inspections.** A qualified solar installer can spot issues—loose wiring, inverter problems, or shading—that drag down performance.
  • **Monitor your output.** Most modern systems come with monitoring apps. If your production suddenly drops, that's worth investigating.

    • Long-Term Planning

    When you work with a solar company to size your system, they factor in this gradual decline. A well-designed system accounts for 25 or 30 years of operation, including the slow efficiency loss. Your installer should explain what to expect over time so there are no surprises.

    For San Diego homeowners, this is especially relevant. Our sunny climate means even a panel operating at 80 percent output is still producing substantial electricity. That's one reason solar makes financial sense here.

    The Bottom Line

    Solar panels do lose efficiency over time—slowly and predictably. It's not a reason to avoid solar. It's just part of the picture you should understand before you invest.

    When you're ready to explore solar for your San Diego home, talking to an installer who can walk you through the real-world expectations is key.

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    About Apollo Home Power

    Apollo Home Power is a San Diego-based solar company serving homeowners in the region. To discuss what to expect from a solar system over time and get answers to your questions, call the business phone or visit https://apollohomepower.com.

    Apollo Home Power

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