As a module that can generate electricity from both front and back sides, the backside of a bifacial module can also receive scattered and reflected light from the environment in addition to the normal power generation from the front side, so it has a higher overall power generation efficiency. Maysun provides the following information on how to maximize the efficiency of double-sided modules.
Purchase advice - choose double-glass solar panels
In addition to choosing a high power solar panel, you should also pay attention to the package of the module if you want to generate high efficiency. The double-sided module will be covered with a layer of glass on the front side, and the reverse side will be encapsulated by a transparent backsheet or glass, called double-sided single-glass and double-sided double-glass, Maysun recommends the double-sided double-glass module for you.
1. The glass of double-glazed modules has high wear resistance and is suitable for various applications such as high temperature, high humidity, desert and snowy environment.
2. The glass insulation is better than the backsheet, which meets higher system voltage and saves the cost of PV system;
3. the attenuation of ordinary modules is about 0.7%, and the attenuation of double-glass modules is about 0.5%;
4. high power output per unit area and 5% – 25% increase in power generation;
5. The warranty period is up to 30 years, compared to 25 years for other modules.
Installation recommendations
Double-sided double-glass modules can increase the power output of the module by 20-30% when the conditions are ideal. And the background reflectivity of the installation location determines how much power is generated on the back side. Only if the back side receives as much reflected and scattered light as possible, the back side can gain more efficiency.
When calculating the array spacing, the main daytime sunlight hours are the main direct reflection area, other areas can only receive diffuse reflections from the sky or surrounding buildings, and the intensity of irradiated energy is weak. The best area to lay the ground material is concentrated in the projection area directly below the module, and can be extended 50 cm – 100 cm to the side of the light source, the specific distance should be calculated according to the module size, bracket parameters and geographical location and other factors, so as to achieve the optimal balance of cost and power generation income.
It is important to note that the DC/AC ratio calculation is also different from that of single-sided modules. The DC/AC ratio for other solar panels can be found in “Important parameters for designing PV systems: DC/AC ratio”.
Increase reflectivity
By choosing the best tilt angle and position of the double-sided module, the system power output can be effectively increased by increasing the ground reflectivity.
1. Common methods to increase ground reflectivity include laying concrete floor, painting reflective white paint, laying white gravel or cobblestone, laying white reflective material, etc. Reflectivity: sand/cement > land > grass > water, the approximate reflectivity can be referred to the following chart, where the reflectivity of cement ground is between 20% and 40%
2. Avoid direct blocking of the back of the PV module by the bracket, or the bracket sandal is at least 5cm away from the back of the module.
3. As far as possible to avoid the convergence box, inverter, cable, etc. on the back of the components of close shading
4. When installing bifacial modules on flat roofs at the best inclination, you can get power generation gain by painting white, etc.
If you live in a high latitude snowy area, the snow on the ground will reflect a lot of sunlight to the back of the PV panel, thus greatly increasing the power generation capacity of the PV panel and easily melting the snow on the module.
Maysun Solar, as a PV module manufacturer with 15 years of professional experience, can provide you with high quality solar panels, click the button below to contact us for a product quote.
