The solar module industry is experiencing rapid growth, with power companies striving to develop high-performance products. One such innovation is the Double-Glass solar panel, which has been on the market for about half a decade. These systems are widely regarded as the most stable solar panels, with minimal degradation potential and an extended lifespan. Double-Glass is considered one of the best solutions for high-quality industrial and residential solar power plants.
The Role of Glass in Solar Panels
Glass, a material known to humanity for over 5000 years, is widely used in industry and everyday life. In the context of solar panels, glass serves as transparent insulation (environmental and electrical) on solar panel faceplates. The backside of a conventional solar panel is usually protected by an opaque backsheet, with the entire structure held together by an aluminum frame for strength and installation ease.
The front glass protects the panel and photocells from mechanical stress, dust, moisture, and more, while allowing sunlight to pass through. Despite the availability of other materials like diamond or “transparent aluminum” (aluminum oxynitride) that could potentially surpass glass in their characteristics, they are significantly more expensive, making glass the preferred choice.
What is Double-Glass?
In recent years, there has been a trend to install glass on both sides of the panel. These designs are called Double-Glass (solar panels with double glass or glass solar panels).
As the name suggests, the double glass module is a structure where the traditional aluminum frames and backsheet substrate are replaced by another glass panel. Thus, the solar cells are completely enclosed in glass. This design ensures that the cells lie on the neutral axis of the connection and therefore do not experience mechanical stress when the module is bent, for example, under snow loads, hail, etc. In addition, the double glass module is less sensitive to moisture or chemical penetration than conventional modules.
Why Choose Double-Glass?
Double-Glass panels offer maximum protection of the solar cell, and with it higher efficiency throughout the entire service life. That’s why for Double-Glass panels, manufacturers promise an output power of at least 87% even after 30 years.
Although such designs are more expensive and heavier than traditional solar panels with an opaque back wall, these disadvantages are outweighed by the advantages inherent in glass solar panels.
Glass is stable in its performance and almost does not age. It is completely impermeable and therefore moisture-resistant – it is the best choice for regions with high humidity. Moisture and oxygen cannot penetrate into such panels, therefore, the aging process of the modules practically does not occur.
The Benefits of Double-Glass Solar Modules
Double-Glass solar panels offer a range of benefits, including increased reliability and durability. The double glass panel without a protective sheet at the back dissipates heat well, and its efficiency decreases more slowly over the period of operation than traditional panels by about 30%. That’s why Double-Glass modules typically come with a 30-year warranty, and the panels themselves generate 25% more energy.
An increase in service life from 20-25 to 30 years entails a reduction in the cost of electricity when using Double-Glass solar panels. The glass solar panel generates more electricity for a longer period of time thanks to guaranteed high performance and longer life.
Increased strength is another advantage of Double-Glass modules. They have better resistance to physical and mechanical stress. So, when standard type solar panels are exposed to wind, snow, hail or other factors, they bend. As a result, microcracks are formed, which reduces the efficiency of the panel. In Double-Glass modules, the glass sheets at the back and front have the same thickness, in the middle, there is no compressive or tensile stress in the neutral layer. This means that the integrated solar cells are optimally protected against mechanical influences.
Resistance to chemical reactions is another benefit. Glass does not react with many chemicals and environmental elements. This property ensures no chemical reactions will occur between the sheet of glass and the solar cells or epoxy resin that holds the panels together.
In Double-Glass, the front and back sheets of glass have the same thermal expansion, meaning they expand and contract at the same rate. Thus, solar cells in Double-Glass panels experience less stress and deformation in hot or cold environments.
The almost complete absence of PID – degradation, which is caused by a potential difference – is another advantage of double glass solar panels compared to standard batteries. In standard solar panels, PID can lead to a decrease in their performance by 30%. The reason is parasitic currents in the modules, especially those that are at ground potential. The effect is enhanced by the penetration of moisture and temperature. Because double glass can isolate moisture from both sides, double glass solar panels are virtually immune to such degradation.
The fire rating of double glazing is higher compared to conventional panels, so changes will be less significant in the event of a fire, especially if the panels are installed on the roof.
Double-layer glass better protects the photocell from mechanical damage during installation and transportation. Therefore, when using Double-Glass, the likelihood of microcracks on photocells by the time the solar plant is started is significantly reduced.
The voltage in systems where Double-Glass panels are used is up to 1500 V (in traditional modules up to 1000 V). This helps to reduce the total cost of the solar power plant when choosing a higher operating voltage of the solar panel (due to the cost of wires, grid inverter, etc.).
Double-Glass solar panels do not use frames, profiles, so there is no need for grounding. The completely smooth glass surface provides only one coefficient of expansion through the use of only one material. The glass surface is easy to clean, it is easy to wash off dirt from it, microorganisms do not multiply on it, for example, moss does not grow.
Today, double glass panels are widely used all over the world and are widely used in industry, household and agriculture. Double-Glass modules are the perfect solution to meet the ever-increasing demands of the dynamic development of the solar energy industry and help it grow in the future.