What Is Solar Panel Degradation and Why Does It Matter?

Do Solar Panels Lose Efficiency Over Time?

Yes — solar panels slowly lose efficiency each year in a process known as degradation. While this doesn’t happen overnight, it’s essential to understand how it works so you can plan your investment and maintain your system effectively.

What Is Solar Degradation?

Solar panel degradation is the gradual decline in the amount of electricity a solar panel generates as it ages. Over time, environmental exposure and material wear reduce efficiency.

The good news? -

Modern panels are designed to degrade very slowly, meaning they can continue generating clean energy for 20–25 years or more.

Causes of Solar Panel Degradation

1. Wear and Tear

Daily exposure to Singapore’s tropical climate — heavy rain, strong winds, and high temperatures — naturally affects solar panels over time.

2. Light-Induced Degradation (LID)

LID occurs when panels are first exposed to sunlight after installation. Efficiency typically drops by less than 1%, after which it stabilises and continues degrading at a much slower rate (around 0.4% per year on average for quality panels).

3. Quality of Panels

Cheaper panels with low-quality components may:

• Lose efficiency faster.

• Require more maintenance.

• Have a shorter lifespan.

4. Poor Installation

Incorrect installation can lead to:

• Electrical hazards (fire, electrocution risks).

• Premature system failure.

• Lower energy generation.

5. Maintenance Issues

Panels covered in dust, dirt, industrial emissions, or bird droppings generate less electricity. Without periodic cleaning and inspections, efficiency losses can add up.

What Is Solar Efficiency?

Solar panel efficiency is the percentage of sunlight a panel converts into usable electricity.

Example: A panel with 20% efficiency converts 20% of the sunlight it absorbs into Direct Current (DC) electricity.

Even with degradation, panels generate power— at slightly lower output each year.

How to Minimise Solar Degradation

While degradation is normal and unavoidable, you can slow it down and protect your investment:

• ✅ Choose high-quality panels with strong performance warranties

• ✅ Work with a reputable installer to ensure safe, correct setup

• ✅ Schedule regular cleaning and inspections to maintain peak efficiency

Final Thoughts

Solar degradation is a natural part of owning a solar system — but with quality panels, proper installation, and consistent maintenance, the impact is minimal.

Most modern systems are designed to perform efficiently for decades, giving homeowners long-term savings and reliable clean energy.

By choosing a trusted solar provider, you can ensure your panels last longer, degrade more slowly, and deliver maximum value.

✅ Pro Tip: Ask your installer about the annual degradation rate and performance warranty of the panels offered. This gives you a clear picture of long-term energy output.