As the name implies, a double-sided module is a module that can generate electricity on both sides of the solar cell. In order to ensure that the back side of the solar panel is also transparent, the front side of the module will be covered with a layer of glass, and the reverse side will be a transparent back panel or glass. Double-glass module is a double-sided module with both front and back sides encapsulated in glass, of course, since it is “double-glass”, the module must be “double-sided”.
When the sunlight shines on the double-glass module, some of the light will be reflected by the surrounding environment to the back of the double-glass module, and this part of the light can be absorbed by the cell, thus contributing to the photocurrent and efficiency of the cell.
Advantages of double-glass modules
Efficiency
Double-glass modules can generate electricity on both sides, so they have additional backside power generation gain than single-sided modules. In the unused usage environment, double-glass modules can gain 5%-30% power generation increment, and the comprehensive power generation efficiency is much higher than single-sided modules.
Long life
Glass is inorganic silica, the same substance as sand, and has more weather resistance, corrosion resistance, abrasion resistance, and fire resistance than any known plastic. UV rays, oxygen and moisture cause plastic backsheets to gradually degrade, chalk up the surface and even break themselves. Glass solves the module’s weathering problem once and for all. This feature makes double-glass modules suitable for various applications such as high temperature, high humidity, desert, seaside, etc., and even more so in areas with high acid rain or salt spray. As a result, double-glass modules have a service life of up to 30 years and a power guarantee of no less than 80%.
Factors affecting the power generation of double-sided modules
Compared with conventional modules, double-sided modules are influenced by many other factors, including the backside power, installation height, scene reflectivity, bracket structure, and module installation method.
Influence of installation method
When installing bifacial cells, the sandal must be located at the edge of the module to avoid blocking the backside of the module by the sandal, and other components (such as inverter) should be reduced to block the backside of the module.
Influence of environment
Due to the different reflectivity in different installation environments, the backside power generation gain of bifacial modules varies from 10 to 30%. According to the data, when the reflective background is white paint, the backside power generation gain is the largest. The higher the reflectivity of the scene, the higher the irradiance received by the backside of the module, and the higher the corresponding power generation gain of the bifacial module system.
Influence of installation height angle, etc.
The installation angle, height from the ground, and orientation of the bifacial module will also affect the power generation of the module system. In distributed rooftop power plants, if the load requirements are met, the bifacial modules can be raised to a higher height from the ground to fully absorb the scattered and reflected light from the back side, which can result in more power generation and revenue.
Application scenarios of bifacial modules
Due to the double-sided power generation characteristics of bifacial modules, the front side absorbs direct sunlight and the back side receives reflected light from the ground and scattered light from the air, so both the front side and back side can generate power, so the installation direction can be oriented in any direction and the installation inclination can be set arbitrarily. Therefore, bifacial modules are suitable for installation in various scenarios, such as agricultural photovoltaic, ground power station, water power station, household roof, highway, parking lot carport, BIPV, etc.
In agricultural PV
In agro-photovoltaic power plants, the white canopy membrane can reflect sunlight to the back of the module, and the power generation gain can be increased to more than 35% compared to conventional modules.
In water power plants
In PV power plants built on fish ponds and reservoirs, using the water surface to reflect sunlight to the backside of bifacial modules can improve the power generation of bifacial module systems, while water, as a natural heat storage body, has a natural cooling effect on the modules, which in turn improves the power generation efficiency of the modules.
With the continuous development of PV module technology, bifacial modules have become an effective solution to reduce the cost of electricity for power plants and improve the ROI of PV power plant projects due to their excellent bifacial power generation performance.
Maysun Solar, as a PV module manufacturer with 15 years of professional experience, also has a variety of double-sided double-glass modules, interested parties can click the button below for product details, or contact us via WhatsApp.
