In recent years, the state has given strong support to distributed photovoltaics, and distributed photovoltaic power generation has gradually entered people’s daily life, The operating efficiency and effect of photovoltaic power plants will directly affect the operation stability and power generation of photovoltaic power plants. After the station is built, it will be found that in the same area, the income of photovoltaic power plants varies. So what factors affect the normal power generation of the power station?
1.Photovoltaic panels accumulate dust
For long-running photovoltaic power generation systems, the impact of panel dust cannot be underestimated. The dust on the surface of the panel has the functions of reflecting, scattering and absorbing solar radiation, which can reduce the transmittance of the sun, resulting in a decrease in the solar radiation received by the panel and a decrease in the output power, and its effect is proportional to the accumulated thickness of the dust.
In addition, because the dust absorbs solar radiation, the photovoltaic panel can heat up, and the dust contains some corrosive chemical modules, which also reduces its photoelectric conversion efficiency.
At the same time, other parts of the photovoltaic panel will also be corroded by wet dust, such as joints, brackets and other parts, and their materials are mostly all kinds of metals, which can easily lead to damage and reduced safety after corrosion. The PV panel may be damaged due to natural factors such as strong wind and earthquake, which may reduce the service life of the PV panel.
In view of the above situation, some small photovoltaic power stations use manual cleaning methods, generally with mops, rubber scrapers or soft rags.
Manual cleaning of large and medium-sized photovoltaic power plants is difficult, and mechanical cleaning is generally used. The cleaning effect of high-pressure water gun is better, so it is widely used in many photovoltaic power plants. In addition, there is mechanical dust removal technology, which uses a mechanized brush combined with an automatic dust removal device for washing photovoltaic panels with water spray, etc., and the dust is swept away by mechanical force.
2.Photovoltaic modules are blocked by shadows
Shadow is the most taboo problem in photovoltaic power plants. Attention should be paid to design and installation, and even more attention should be paid to later operation and maintenance. Common shadows are mainly bird droppings, dust, shade, buildings, fallen leaves, etc.
Therefore, first of all, it is necessary to do a good job of landmark survey. You can choose a suitable location to install photovoltaic modules. Try not to install modules in shaded places. If it is unavoidable, choose a suitable module placement method, which can reduce the Impact caused by shadows.
According to statistics, the power loss caused by shadow occlusion to the system is 10-30%, so the shadow of modules must be paid attention to.
3.Hot spot loss of PV modules
What is “hot spot effect”? Under certain conditions, a shaded solar cell module in a series branch will be used as a load to consume the energy generated by other illuminated solar cell modules. The shaded solar cell modules will heat up at this time, which is the hot spot effect.
The hot spot effect seriously damages the solar cell itself to a certain extent, and part of the energy generated by the illuminated solar cell may be consumed by the shaded cell. The hot spot effect of photovoltaic power plants will directly shorten the service life of photovoltaic modules by 30%. In the long run, it may cause module failure, and in severe cases, it is also the source of fire.
The measures in the module production section include: controlling the reverse current of the battery, controlling the impurities inside the battery, and adopting parallel diode protection for the modules.
The measures on the application side include: adopt batteries (or modules) with good performance consistency, try to ensure that the modules are not blocked during installation, and clean up and clean in time when there is dirt on them, so that the photovoltaic system can maintain a good power output.
Now that a photovoltaic power station is installed, it is essential to develop scientific operation and maintenance habits and master scientific operation and maintenance methods. I hope you can maximize the benefits of your own photovoltaic modules in the daily cleaning operation and maintenance, Any questions please contact us.