Why Do Solar Panels Degrade?

The utility solar panels provide is remarkable, but like any equipment, they also have a life. Generally, the efficiency of solar panels drops 0.5% every year if the build quality is good; otherwise, it can be up to 3%.
Most solar panels have a life of up to 25 years, but their efficiency is around 80% even at that age. However, this is a general case, and their degradation period depends on various factors.

Most of these factors are related to environments such as extreme temperature, humidity, rain, and snowfall. Some factors like rusting, usage and compatibility with inverters also affect it. But the most common factor is their natural degradation process.

Technical Reasons

Light-induced Degradation
Solar panels naturally degrade up to 3% during the first 1000 hours after installation. During this period, their photoconductivity is diminished, which causes degradation. But after this period, no major degradation happens due to photoconductivity diminishing.

Potential-induced Degradation (PID)
The inner components of solar panels operate at the same voltage, but if they don’t, it causes potential-induced degradation. Usually, this happens when there are any blank cells or voltage leaks. This causes a massive flow of electrons and voltage difference.

This only happens sometimes, but if a solar panel is prone to such a problem, its efficiency can decline by up to 30%.

Bussbar Stress
Bussbars also cause degradation in solar panels and cause cracking as busbars are connected between cells through solders. These solder points put pressure on the solar cells.

The situation improves with solar panels with more busbars because they have several solder points. Since there are several solder points, the overall stress is divided, reducing the chances of cracking.

Hotspot Stress
Solar panels do not maintain the same temperature over the entire surface. Sometimes due to microcracks or solder spots, some regions heat up more than the rest of the surface. These hotspots also affect the overall efficiency and life of solar panels.

Climatic Reasons
Once the solar panels are installed, they remain in one place for the rest of their life. Since they are exposed to the sun and clouds, they go through different climatic situations.

One of the key factors that affect the life of solar panels is heat. It severely affects their internal junctions, which results in degradation.

There are different kinds of solar panels designed for different climates. Some solar panels are designed for high temperatures and can withstand up to 85 degree Celsius, and some are designed for low temperatures.

Generally, most solar panels have a temperature limit of up to 47 degrees Celsius. Beyond this temperature, the heat starts degrading the panels. In extreme cases, the glass starts cracking, leading to poor light exposure and causing a decline in efficiency.

Humidity corrodes electronics and sometimes causes unwanted connections, which leads to malfunctioning and shorter life. Similarly, after a few years of use, it corrodes the frame of solar panels, and the wear and tear start increasing. If humidity enters the internal circuitry of panels, it corrodes that as well, which causes further degradation.

Humidity also affects the efficiency of solar panels if it beyond the operating range.

Hailing does not directly affect solar panels except for the impact when it hits the panel. Solar panel glasses are known to have broken down due to hailing in northern regions. In fact, in some cases, the impact of hailing was so strong that it permanently damaged solar panels.

Solar panels need direct exposure to sunlight for maximum efficiency. But some regions are prone to frequent dust storms, which constantly cover the panels. Any dust on the top of solar panels works like an obstacle and blocks exposure to sunlight.

If the sunlight is intense, the solar panels still generate electric power but with declined efficiency. However, the panel generates minimal power if the sunlight is not intense.

UV Exposure
The backsheet of solar panels protects the cells from external stresses and works as an insulator. But the UV exposure from sunlight discolors the backsheet and degrades it. This degradation affects the efficiency of backsheet to protect the cells, which ultimately starts damaging the cells.

How to Prolong Solar Panel Life?
Even though solar panels naturally degrade with time, you can prolong their life with extra care. Below are some factors that can help slow down their degrading process.

The quality of your solar panels directly impacts their degradation process. The higher the quality, the lower the chances of corrosion, seal leaks, glass breakage and micro-cracks, and cell degradation. Always choose a quality brand that builds panels according to international standards.

Besides the quality of your solar panel, the quality of your inverter, cables, and other equipment also matter. Wisely choose a well-reputed brand like Bahoo Power to enjoy the output of your solar panel for a lifetime.

Make sure your solar panels are properly installed with compatible equipment. Improper assembling can also lead to early degradation. Always hire professionals to install solar panels and other equipment.

Regular Maintenance
Solar panels must be regularly cleaned for protection against rusting and dust. This also helps keep their efficiency high. Moreover, also check the connections and any signs of seal leaks.

In some regions, especially in the USA, the population of pigeons is high, leading to pigeons sitting and pooping on the panels. Some solar installation companies offer enclosures and other equipment for this problem. Pigeon poop not only blocks sunlight but also causes corrosion on solar frames.

Final Thoughts
Solar panels can provide power for a lifetime if given good care. Today, the oldest known solar panels are still operating at the age of 60 years and still working well. This explains how the degradation of solar panels can be slowed down if they are properly maintained.