Delamination is the separation of layers in a material, and in the context of solar panels, it refers to the separation of layers within the panel itself. Various factors, including poor manufacturing conditions and lower-quality backing sheets, can contribute to it.
Delamination can be harmful to a solar panel and is a death sentence. However, production quality is the most important factor influencing whether or not delamination occurs.
Hot spots on a solar panel are areas of the panel that get hotter than usual, resulting in poor performance and even panel damage.
In addition, incompatibility between the electrical characteristics of the solar cells within the panel or microcracks frequently causes these hot spots, which can result in uneven power distribution an increase in temperature in specific areas of the panel, and finally, permanent damage.
What is delamination on a solar panel; What causes it?
Delamination of solar panels is the separation of layers in a material, it refers to the separation of layers within the panel itself.
This can be caused by various factors, such as the manufacturing shortening of the lamination time to save electricity, faults such as uneven surface in the lamination machine, and poor quality panel backing sheet material.
The delamination of solar panels is a death sentence. It is very damaging because it will let water enter the panel over a relatively short time and cause corrosion in the soldering and busbars, leading to earth faults. Solar panels with delamination issues need to be replaced urgently.
The quality of production is the most influential factor determining if delamination occurs. Incompatible layers of glass and plastic, poor-quality laminating machines and ineffective temperature regulation are some issues that can arise in production.
However, as knowledge and manufacturing processes for solar panels have drastically improved in recent years, the likelihood of poor production results has declined. Unfortunately, other factors can still damage solar panels beyond repair.
Hot spots on a solar panel are selected areas with higher-than-average temperatures, which can result in decreased performance and even panel damage.
One of the critical reasons for hot spots is a cracked solar cell. As the naked eye cannot see, these cracks, called microcracks, can occur in the factory, the handling during transport and distribution, or their installation. In addition, the impact of large hailstones or other objects like cricket balls can also cause microcracks.
This is why one seeks to employ quality installers who know how to handle the panels without causing damage.
Incompatibility between the electrical characteristics of solar cells within the panel can also cause hot spots. For instance, if there’s a significant variation in efficiency between cells, it’s typically due to poor sorting and categorizing of cells during the panel production process.
This can result in an uneven distribution of power and an increase in temperature in specific areas of the panels where a high-current cell is adjacent to a lower-current-rated cell. The lower current cell causes a blockage of power and resistance and generates heat, leading to a hotspot.
Poor quality, uneven soldering, and poor connection between solar cells can also create resistance leading to hotspots.
Factors, such as shading by trees or chimneys, aerials, buildings, dust or debris accumulation, or panel damage, can cause delamination on solar panels. Visual inspection of the panel may reveal hot spots in some cases, as the affected areas may appear darker or discoloured. Sometimes the backing sheet has a burn mark on it.
Delamination of solar panels can have serious consequences. They can initially reduce the panel’s overall performance and efficiency. The result over time will be that the heat causes the panel’s glass to crack and, at that point, is beyond repair.
In extreme cases, delamination can cause a solar panel to catch fire, even though this is very seldom, as nowadays solar panels have fire retardant material in their backing sheets.
Prevention of delamination and hot spots
To prevent the formation of delamination on solar panels, it is essential to choose a quality solar panel brand and a conscientious quality installer.
Regularly cleaning and maintaining the panel is crucial because dust and debris worsen the issue.
Additionally, it’s essential to have professionals design the system for the site’s conditions, considering factors like panel position, potential shading, climate, environmental conditions (e.g., coastal), and the electrical and design characteristics of the solar panels.
In conclusion, delamination on solar panels can be a severe problem, leading to lower performance, damage beyond repair and even safety concerns. Selecting a quality solar panel to start with, performing regular system checks and booking a CEC-approved quality solar company is the key to preventing the delamination of solar panels and ensuring optimal performance.