Recently, the weather in the south seems to be "crazy". Just after enjoying two days of "spring", the temperature dropped sharply and I had to put on my down jacket. Is this "late spring cold"?
Not only in the south, but also in Mohe, the far north of China, which is the north by traditional standards, has also ushered in its "late spring cold" - minus 43℃. "People say that the north of the desert is very cold, and the north wind is biting and the snow is continuous." The ancients were not deceiving me. Because of this, Mohe's extremely cold climate has also made it a treasure land for verifying the reliability and power generation performance of solar panels.
In recent years, with the continuous growth of photovoltaic installed capacity, the issue of photovoltaic land use has become one of the core factors restricting the growth of photovoltaic investment in the later period. Since the "14th Five-Year Plan", more and more land has been restricted or subject to additional use conditions, the application scenarios of photovoltaic modules have been continuously expanded, and the operating environment has become increasingly complex. Extremely cold areas have gradually become important areas for the layout of photovoltaic power stations.
Photovoltaic modules that operate outdoors for a long time will inevitably be tested by complex and changeable climate and environmental conditions. These tests will not only affect the reliability of the modules, but also have a significant impact on their power generation performance and power generation.
In Mohe City, Heilongjiang Province, the northernmost part of my country, there is a unique extreme cold environment at the northern foot of the Greater Khingan Range and the southern bank of the Heilongjiang River. The lowest temperature in Mohe City can reach minus 53 degrees Celsius, and the ice period can last for half a year, providing an extra-long time and an excellent test scene for the performance verification of photovoltaic modules. In the past 2024, the average temperature in Mohe was below 0℃ for 8 months, the lowest temperature was -45.3℃, and the snow thickness of the modules was as high as 20cm or more. The harsh conditions can be seen from this.
With the completion and commissioning of the Mohe Extreme Cold Test Park of the National Inspection Group, it has attracted 39 photovoltaic companies to settle in, including many leading companies such as Longi, Tongwei, Jinko, and JA Solar. Here, the photovoltaic modules of major companies face extremely severe tests, not only extreme low temperatures, but also complex climatic conditions such as strong winds, heavy snow, and temperature differences between day and night. These complex and changeable environmental factors have placed extremely high demands on the material properties, mechanical strength and power generation efficiency of photovoltaic modules.
Test of material performance
The extremely cold environment poses a huge challenge to the material properties of photovoltaic modules. First, encapsulation materials such as EVA film will gradually lose their elasticity at low temperatures. When the temperature drops below -30°C, the film becomes brittle and the protective performance is greatly reduced. In addition, the PET material in the backplane has reduced elasticity and weakened impact resistance at extremely low temperatures, which can easily lead to hidden cracks or wear. These changes will directly affect the sealing of the module and the protection of the cell, and thus affect the power generation performance and service life.
Test of mechanical strength
In extremely cold areas, photovoltaic modules must not only withstand extreme low temperatures, but also cope with mechanical stresses such as strong winds, heavy snow, and uneven snow loads. Low temperatures will significantly reduce the impact resistance of photovoltaic glass, and the uneven pressure caused by snow accumulation may cause the module to deform or damage. In extremely cold areas such as Mohe, the thickness of snow in winter can reach several centimeters, and the low temperature lasts for a long time. The components need to have higher mechanical strength to resist these external forces. In addition, the inclination angle of the components during installation will cause greater pressure on the bottom of the components when the snow slides down, further increasing the mechanical load.
Test of power generation performance
The extremely cold environment also has a significant impact on the power generation efficiency of photovoltaic modules. On the one hand, low temperature will cause the output voltage of photovoltaic modules to increase, which may exceed the input voltage range of the inverter and affect the normal operation of the inverter. On the other hand, the solar altitude angle is low in winter, the sunshine time is short, and the solar radiation energy is reduced, which further reduces the power generation efficiency. In addition, snow cover will block the sunlight and reduce the power generation of the components, and excessive snow may cause the components to freeze, further affecting performance.
In other words, the arrival of leading photovoltaic companies in Mohe not only reflects their firm confidence in the performance of their photovoltaic products in extremely cold climates, but also reflects the forward-looking layout and technical strength of photovoltaic companies in building photovoltaic power stations under extreme climate conditions.
