Analysis of Photovoltaic Upstream Industry Chain
The photovoltaic industry chain includes 6 links including silicon material, ingot, slice, cell, cell module and application system. The upstream is the link of silicon materials and silicon wafers; the midstream is the link of cells and battery modules; the downstream is the link of application systems.
From a global perspective, the number of companies involved in the six links of the industrial chain has increased significantly, and the photovoltaic market industry chain has a pyramid-shaped structure. In the context of rising global energy demand, high traditional energy prices and increasing attention to environmental issues, renewable energy has developed rapidly around the world.
Today, let’s talk about the photovoltaic upstream industry chain
Process from Silica – Silicon Ingot – Polycrystalline Silicon (Frosted Ingot) – Monocrystalline Silicon (Mirror Ingot) – Wafer
1. Silica is converted into silicon ingots from submerged arc furnace through reduction reaction (after cooling, the purity of silicon in smelting industry is between 98%-99%);
China is the country with the largest silicon production in the world, accounting for about 70% of the world;
The industrial silicon is then purified into polycrystalline silicon rods, which can be used in the photovoltaic industry and made into solar modules and panels, accounting for about 70% of the world;
Monocrystalline silicon is divided into photovoltaic grade monocrystalline silicon (6 9s), semiconductor grade monocrystalline silicon (11 9s), the biggest difference is the different purity;
Therefore, the single crystal silicon used in semiconductors is different from the single crystal silicon used in photovoltaics, and the semiconductor part in my country only accounts for about 5%;
China’s production capacity level is the highest in the world, accounting for more than 85% of global production capacity;
2. Silicon wafer
Cut off the silicon head and silicon tail of the silicon rod, detect the resistivity of the rod body, detect the axial impurity concentration, and then use a diamond wire loop to cut the silicon segment;
Use tumbling to grind the bar body, and then grind the positioning edge;
Then use the multi-segment cutting machine of diamond wire to cut the silicon segment into the silicon wafer;
The core enterprises of global photovoltaic silicon wafers are Chinese enterprises. In the entire industrial chain, silicon materials, especially high-purity silicon materials, have the highest gross profit margin.
Due to the rapid development of the photovoltaic industry in recent years, the supply of silicon materials has been in short supply, and the price of silicon materials has been rising steadily.
In order to save silicon material, most photovoltaic factories in China do not use band saws to cropping silicon ingots in the process of processing silicon wafers, but use diamond wires loop to cropping silicon ingots, such as LONGI, WAFER WORKS, Integra TDS,s.r.o. JinKo Solar , ON Semiconductor etc.
Below is a video of a diamond wire loop cropping silicon ingot for your reference：