What is the Lifespan of Solar Panels?

What is the Lifespan of Solar Panels?

 

The typical lifespan of a solar panel is about 25 years, but that doesn't mean they suddenly cease to function after this period. Instead, they continue generating electricity, albeit with gradually diminishing efficiency beyond the 25-year mark.

 

Several factors affect the longevity and performance of solar panels. This article explores the concept of solar degradation and the role of warranties in ensuring sustained electricity production from solar panels over time.

 

Understanding Solar Panel Degradation and Efficiency Over Time

 

Similar to how the roof of your house or your car gradually wears down, solar panels also experience degradation over time. This means that while solar panels require minimal maintenance, those planning to use solar energy for beyond 30 years might need to consider replacing their panels to maintain optimal electricity production.

 

Research by the National Renewable Energy Laboratory has shown that the average rate of efficiency loss in modern solar panels is about 0.5% per year. This implies that a solar panel's efficiency decreases by 0.5% annually from its original performance level. The quality and technology of solar panels can vary, leading to some instances where the degradation rate reaches as high as 3% annually. For the purpose of clarity, we'll focus on the median degradation rate of 0.5%.

 

With a 0.5% annual reduction, a solar panel would operate at 99.5% of its original capacity after one year, often seeing a slightly higher loss in the first year than in subsequent years. After 25 years, at this steady rate, a solar panel would still function at over 80% efficiency.

 

To put this into perspective, consider a solar panel that generates 500 kWh in its first year. At 80% efficiency after 25 years, it would still be capable of producing approximately 400 kWh annually. While the solar industry generally considers 80% efficiency as the benchmark for a solar panel's "end of life," panels can actually continue to produce electricity well beyond this point.

 

Understanding Solar Panel Warranty Coverage

 

To mitigate the impact of degradation, solar manufacturers provide performance warranties, ensuring that solar panels continue to generate electricity efficiently over time. The standard performance warranty guarantees that solar panels will retain at least 80% of their original output after 25 years. Additionally, some warranties offer a 90% production guarantee for the first 10 years.

 

The second type of warranty is the equipment guarantee, addressing potential issues beyond normal wear and tear. These warranties often span 10 years and cover manufacturing defects, premature deterioration, and damage from environmental factors like severe hail or strong winds.

 

Furthermore, when employing a company for the installation of solar panels, customers might receive a workmanship warranty. This separate guarantee covers installation-related issues, such as roof damage, ensuring that the installation process is as seamless as the solar panel's operation.

 

Conclusion

 

With ongoing advancements in solar panel technology, the future could see solar panels surpassing their current average lifespan. While the norm is for panels to maintain around 80% efficiency after 25 years, there have been instances of panels from the 1970s still functioning at this efficiency level, marking over four decades of renewable energy generation. Additionally, there's a growing practice of donating older, less efficient panels to underserved communities, where they continue to provide valuable energy production despite their age.

 

This article aims to shed light on the longevity of solar panels, hoping to address common questions regarding their lifespan and ongoing utility.