How Photovoltaic Panels Generate Power?

1.  Principle of photovoltaic power generation

Sunlight illuminates the semiconductor p-n junction to form a new hole-electron pair. Under the action of the built-in electric field of the p-n junction, the holes flow from the n region to the p region, and the electrons flow from the p region to the n region. current.

2. Topcon battery

It was proposed by Germany in 2013 that the base material is N-type silicon. By adding oxides to increase the reflection of the backplane and improve the photoelectric conversion efficiency, it can be understood as an upgraded version of PERC cells in essence.

The representative manufacturers are LONGi, Jolywood, Jinko, Trina Solar, etc.

Advantages of this kind of battery are higher limit of photoelectric conversion rate (28.7%), lower attenuation rate, and the production line can be upgraded based on the current PERC production line. At the same time disadvantages are manifested as well, like he cost is currently high, the process is more complicated, and the yield is low. The conversion rate of commercial Topcon batteries produced now is about 24.5%.

3. HIT battery

Proposed by Japan in 1990, the base material is N-type silicon, also known as HJT/SHJ/HDT battery, and the photoelectric conversion efficiency is improved by adding amorphous silicon material film to the N-type silicon wafer base.

The representative manufacturers are LONGi Co., Ltd., Tongwei Co., Ltd., Maiwei Co., Ltd., etc.

Advantages: The process is simple, the photoelectric conversion rate is high (27.5%), all of which are low-temperature processes, and the silicon wafer is thinner and theoretically lower in the future.

Disadvantages: The cost is temporarily high, the production line needs to be rebuilt, and it cannot be transformed on the basis of existing PERC battery production lines.