Internal Corrosion and Delamination in Solar Panels: What You Need to Know About 0

Solar panel's Corrosion and Delamination

When scientists at Bell Labs first discovered the possibility of silicon creating electric charge after being exposed to sunlight in the 1950s, solar technology has been evolving ever since. It was after 1954 that solar panels started becoming a valuable source of electricity among many countries. 

Solar power systems allow consumers to reduce their dependence on traditional sources of thermal and electric energy. It consists of panels and an inverter (string, microinverter, or power optimizers) that convert solar power to generate electricity for a household. 

Solar panels comprise a single layer of silicon solar cells, a glass covering, and a metal frame with wirings and circuitry to collect electric current from the cells. Each panel or solar module measures about 4ft by 6ft and weighs 14 to 15 kg. 

The functionality of solar panel systems is generally referred to as the photovoltaic effect. This is when sunlight hits a cell and sets the electrons in the silicon in motion, initiating electric current. If you are among those who have adopted solar energy, maintaining your solar panels can be handy. But you can learn some professional tricks below: 

Internal Corrosion and Delamination in Solar Panels

Internal corrosion, or rusting of the panels, happens when moisture seeps inside the system. There must be no air, nor water, that gets inside each module, or some serious damage will occur if left unattended. It’s also best when you get a service provider nearby. For example, if you live in Brisbane, you can check out the best solar installers Brisbane has. 

Each panel component (solar cells, glass layer, back sheet) must be appropriately laminated in a vacuum. But, things could go wrong within the lamination process, too. It’s either done poorly or in haste. Regardless, this mistake in the operation may cause delamination. 

Delamination occurs when laminated solar panel components are detached from each other. Failures in an installation like ill-fitted module trim can attract moisture to the solar panels, where bubbles start to occur. And the one responsible for this is cheap manufacturing. 

When panel components are contaminated, bonding between each layer is corrupted and will begin separating over time. In the industry, manufacturers often try to produce solar panel systems in high numbers to meet quotas. This will then result in poor quality for both product build and selection. Below are some points of interest: 

  • Use of substandard plastic quality
  • Unclean and incompatible glass or plastic layers
  • Lack of introduction regarding proper plastic thermal properties
  • Low-grade laminating machine
  • Poor pressure and temperature regulation

As discussed above, moisture will lead to corrosion, showing visible signs like dark spots on the solar panels. You will notice an incredible amount of reduced panel production as rust continues to spread in your system. Remember, the darker the corroded areas are, the lower the efficiency of your panel production. 

You might ask, is delamination that inevitable? Here’s the case, after your system’s modules have been used for a certain amount of time, delamination is most likely to occur. That is why it is possible to encounter slowed cell performance and energy transmission without a proper visual inspection by your local PV installer. 

Counting on the severity of the delamination, the problem usually begins at the edge of the solar panel until it spreads. Glass-manufactured and thin-film or frameless PV panels, in particular, can suffer the most damage when corrosion and moisture issues go uncontrollable. 

This then encourages the build-up of interconnecting corrosion, resulting in moisture ingress. In your solar panel system, there are inherent voltages that drive ions and may further promote rusting. 

You will notice this happening once there is a decrease in the IV curve’s fill factor. Upon coordinating with a professional, a solar cell inspection called electroluminescence will then be administered. Your trusted expert may mention a process called encapsulant improvement to minimize damage in your system. 

You must take immediate action when you see signs of delamination in your solar panel system. Some indicators of failure mechanism include imperfections or crumple on the plastic’s rear surface. You may also want to examine other problems that your solar panel system may encounter, such as the following: 

Snail Trail Contamination

Snail trail contamination usually happens years after its production. If you start noticing discoloration in your panel, there is a higher chance of experiencing the said problem. Although snail trail has many causes, the main reason can be pointed at faulty silver paste at the front metal during the manufacturing process. 

This invites moisture in your solar panel, which will then lead to oxidation between the encapsulation material and the silver paste. After this happens, acetic acid, hydrogen, and silver oxide are released, causing a chemical breakdown at your front panel. This reaction will leave “snail trails,” hence the name, reducing your solar panel system’s performance. 

PID Effect

PID effect is connected to the amount of negative potential that a PV module can only deal with under normal working conditions. PV modules create strings by being connected in a series to distribute voltage depending on your solar panel system’s type of inverter. 

The Potential Induced Degradation or PID effect in solar PV panels affects your system by consistently reducing the power of the modules. This effect then affects the expected module potential with reference to the ground. The high voltage between the front surface and the encapsulated solar cells is generally behind this effect. 

As it can’t be imperceivable by the naked eye, it can decrease a solar cell’s performance, especially with high temperature and humidity encouraging the process. Make sure to inspect your system months after the installation, as the PID effect can happen anytime. 

Hot Spots

Hot spots are areas on your solar panels that become overloaded over time, therefore causing the system to be abnormally warm. There are three leading causes of hot spots that operators and owners should take care of: mechanical damage, soiling/shading, and internal module failures. 

Mechanical damage includes bent or broken frames, modules colliding with other objects or with each other, damaged glass layers, and busted fixturing. Soiling/shading happens when there is vegetation overgrowth, overhead objects, surface fouling, and foreign particles above and around your solar panel system. 

Internal module failures occur when there is mishandling of the modules during transportation or installation, unresolved racking issues, and improper clamping/fixturing. This can bring microcracks and cracks in your modules, which can weaken your system’s overall performance. 


Micro-cracks are inevitable in every crystalline PV panel. This problem may occur during the manufacturing process, transportation, or plain neglect in installation. Although micro-cracks don’t result in immediate performance reduction, this can grow into large cracks due to weather and seasonal changes and thermal tension, resulting in solar cell damage. 

As panel cells are installed in a series circuit, this damage can spread into the whole panel itself. The more damaged cells, the less efficient your solar panel system becomes as it affects a higher module percentage. 

Proper Maintenance on Solar Panels

Solar panel systems can last you for years with minimum maintenance needs. But, caring for it regularly can give you more benefits than you can think of. Not only does it keep your solar panels looking shiny and new, but it also saves you a significant amount of expenses. Learn more about how to avoid specific system problems and general solar panel maintenance here:  

Internal Corrosion and Delamination

You can only ensure that there will be no internal corrosion nor delamination in your solar panels when you purchase a system with a trusted supplier. When shopping for a solar panel system, you must ask them first about the brand of their lamination machine. 

Familiarize yourself with good lamination brand machines to distinguish the best from the worst ones. Asking about their production process and if they observe a good SOP among their workforce can help you know which supplier is good to work with. Lastly, make sure that the manufacturer has all the necessary corrosion certification to avoid problems in the future. 

Snail Trail Contamination

Like how you avoid corrosion and delamination, outsourcing a good-quality raw material from your solar panel supplier can help you prevent snail trails. Never be intimidated to ask about their IQC (Incoming Quality Control) process and assess if they’re as strict as they ought to be. IQC tests each raw material to ensure that the system functions properly. 

But if you already bought a solar panel system and noticed snail trails, you can work with a reliable electrician and replace it with parts that have durable encapsulation materials. This can help you prevent water from seeping inside your system. You also need to handle your panels with much care to avoid micro-cracks. 

PID Effect

Interaction with the surrounding environment and the solar power system itself is the leading cause of PID. As inevitable as it is, you can still take a few precautions to keep your system from encountering damages such as this. First, you can shop for a solar panel system with a built-in PID resistance. 

Materials such as encapsulation, diffusion barriers, and glass layers have a high impact on PID, so make sure to inspect its parts before purchasing. Several studies have shown that sodium exhibits several causative factors making your front surface more susceptible to damage. 

Hot Spots

As discussed above, hot spots have three leading causes: mechanical damage, soiling, and internal module failures. You can avoid mechanical damage by choosing a suitable module for the right installation site. Therefore, a prior inspection must be done by your manufacturer. 

If you live in an area prone to hail storms and high winds, you should select modules tested to withstand extreme weather conditions. You can work with a trusted test lab or manufacturer to design unique test programs suited to the installation site’s situation. 

As for soiling/shading, regular maintenance can do you wonders. But if the problem has gone worse, you can work with a module-level smart electronic to lessen risks and hazards. Lastly, you can avoid internal module failures by conducting a complete IR inspection and sampling electroluminescence imaging to identify damage. 


You need to carefully examine three areas to prevent micro-cracks in your system: manufacturing, installation, and construction. Working with a supplier that has an efficient micro-crack-prevention plan makes the job a lot easier. 

This is crucial as trusted suppliers and professional PV installers purchase solar panel systems through authorized distribution companies only. You can extend your examination process by asking your supplier if they have a testing procedure that guarantees the quality of their product.

You may also ask if they have a credible reputation among consumers, a well-structured supply chain, and a good warranty program. It is also vital that you carefully monitor your system upon installation. Look for solar panel monitoring services in your area to check if your PV system is still performing its best. 

General Maintenance Tips

  1. Document your solar panel’s daily performance. You may jot down how much energy it has produced at a particular time of the day and put a note when it’s a cloudy day. It can be inconsistent, so better consult with your manufacturer to adopt an efficient monitoring system. 
  2. Make sure to keep your solar panels away from the shade. This can affect your system’s energy production, making its performance more inefficient than when you first bought it. 
  3. Cleaning solar panels can be difficult and risky if you’re still a new system owner. It is better to have automated cleaners installed or schedule an appointment with your local solar panel maintenance companies. 
  4. Never forget to check your solar panel system a day after a severe weather event like a hurricane, tornado, or bad storm. You may incorporate online monitoring in your maintenance process, but better yet, use your home insurance. Contact your local installer to have your panels repaired or replaced in case of apparent damage. 


Owning a solar panel system can be handy, especially if you’re a new owner. You’re most likely to encounter several problems and damages in your system, but you can always solve them. With the help of professional installers and electricians, repairing, maintaining, and even replacing your solar panel system will become an easy task.

In the fight against the climate crisis, Willie Jiang believes that content marketing can push the energy revolution along at a faster pace. Having helped countless brands grow their organic traffic by 10X and became the CMO of, he is sharing his insights with the solar energy industry. If you want to publish your articles on SolarFeeds Magazine, click here.
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