How to Improve PV Power Efficiency as Rainy Weather Approaches

As we said before, power generation is directly related to the radiation of sunlight, and in the case of rainy weather, the power generation of PV stations will be very low. So, is there no power generation at all from a PV station in rainy weather? Not, in fact, the current photovoltaic module in low light conditions can also do a certain degree of power generation, which is the rainy weather photovoltaic power station will also generate electricity. Although there will be a certain impact, but the average annual power generation is able to achieve.

First of all, let us first understand the key factors affecting the efficiency of cloudy weather power generation：

1, light strength: this is the most direct factor affecting the efficiency of photovoltaic panel power generation. On sunny days, the sunlight is strong and direct, the photovoltaic panel receives a large number of photons, high energy, so the power generation efficiency is high. On cloudy days, clouds shade part or all of the sunlight, PV panels receive a reduced number of photons, energy reduction, resulting in a decrease in power generation efficiency.

2. Spectral profile: The spectral profile varies under different weather conditions. On sunny days, there are more short-wave components (such as blue light and violet light) in the spectrum, and the energy of these photons is higher, which is helpful for the power generation of PV panels. On cloudy days, the spectrum may contain more scattered light, and the energy of these photons is lower, contributing less to the power generation of PV panels.

3. Temperature effect: The temperature is relatively low on cloudy days, and the temperature of the PV panel will be reduced accordingly. The power generation efficiency of PV panels is closely related to its temperature. Generally speaking, the power generation efficiency of PV panels will decrease with the increase of temperature. Therefore, under cloudy days, the power generation efficiency of PV panels may be improved because of the lower temperature, but this enhancement is usually not enough to make up for the impact of lower light intensity.

For many Asian countries, the rainy season is approaching, and the question on everyone's mind is: Will the PV station run out of power when it rains? We can tell you with certainty that it won't!Assuming that a standard photovoltaic panel generates 20% electricity on a sunny day, its efficiency may drop to around 10% on a cloudy day. This means that in the same amount of time, a PV panel on a sunny day will generate twice as much electricity as on a cloudy day. Of course, this data is for reference only, and the actual difference may vary depending on the type and quality of the PV panels, the angle of installation, and the local climate.

In rainy or hazy weather with low solar energy, the PV power system will not work if the operating voltage of the PV power system does not reach the start-up voltage of the inverter. Since the grid-connected power generation system is grid-connected to the power grid, when the PV power generation system fails to operate, the power from the power grid will be automatically supplied, so there is no problem of shortage power in both rainy weather and haze.

For the people who used solar system and invested tens of thousands of dollars in the power station,how to do to ensure that power generation is stable and not affected by the weather? Teach you three tricks to take care of power generation!

1. Do a good job in the pre-design of the power station

  Power station in the design, you need to choose the right location, such as photovoltaic power station construction on the roof, to take into account the roof fixed load, wind pressure load, snow pressure load, earthquake load, generally in accordance with the "Building Structural Load Code", because only in this way can avoid the power station damage from weather. In addition, for some specific situations, such as roofs, carports, etc., waterproofing and drainage need to be considered, and bracket systems with drainage parts can be chosen.

 2. Do a good job of installing the PV racking matrix

    Racking matrices are in the whole photovoltaic power station to support the role of solar panels, while the design of the racking matrix orientation and photovoltaic power station has a close relationship with the power generation. First of all, the installation can not be random, the power station installation process should be facing south, as the name suggests is the power station facing south, so that you can fully accept the sun's light. Installation angle is theoretically equal to or close to the local latitude, arrangement and spacing needs to be combined with local sunshine and roof structure size. Different regions with different light conditions and latitude require different product matching solutions.

3. Choose good equipmen

Here the equipment modules, inverters, brackets. For mainstream inverter manufacturers are basically IP65 protection level, with waterproof performance, but the impact of prolonged rainy weather on the equipment is still very large. If the choice of photovoltaic products can not withstand prolonged rain, power generation will not be able to come on and how to talk about revenue? Photovoltaic brackets are immersed in water for a long time, how to do 10 years without rust, 20 years of steel does not reduce, 25 years still have a certain structural stability, which has a special requirement for the material of the mount. For different needs, each component such as beams, purlins, ground piles need to choose different steel hardness and even materials!