Analysis on the pull of the hottest crystal silico

Analysis of the pulling effect of crystalline silicon cell projects on the photovoltaic industry chain

after Wuxi has yet to deduce the apotheosis of solar energy, benefiting from the long-term benefits of the solar energy industry, in recent years, Chinese enterprises have launched a large number of crystalline silicon cell projects, making the annual production capacity rapidly exceed 3200 megawatts, and become the world's largest photovoltaic industry base. In the photovoltaic power generation industry chain, the battery is undoubtedly the central link with the most technical characteristics, the most development potential and the most driving role. The development of crystalline silicon cell chip projects can drive the development of polysilicon materials, pull rod chips, battery modules, power generation projects, application products, photovoltaic chemical industry, photovoltaic machinery and other related industries. This paper introduces the components of the photovoltaic industry chain, in order to contribute to the balanced development of the photovoltaic industry chain

1. Polysilicon material

the price of polysilicon material has increased by 10 times in just four years from $24 per kilogram in 2004 to $480 now, and 4. Preliminary correction of the main body: there is no market at the two vertical and horizontal positions of the two pillars, and the supply exceeds the demand, which has become a bottleneck factor in the development of the industrial chain. The main reasons for this situation are that the refining of polysilicon materials requires large capital investment (the new polysilicon plant requires an investment of $100/kg), and more energy consumption (power consumption per kilogram of polysilicon materials) due to the computer collection of test data and high technical threshold. At present, more than 85% of the international production processes for producing high-purity polysilicon materials use the improved Siemens method. It uses chlorine and hydrogen to synthesize HCl. HCl and industrial silicon powder synthesize SiHCl3 at a certain temperature, and then SiHCl3 is separated and purified. The purified SiHCl3 is subjected to chemical vapor deposition reaction in a hydrogen reduction furnace to obtain high-purity polysilicon. This kind of high-purity polysilicon material requires high purity, which generally needs to reach 99. Above 9999%. Driven by the seller's market and high profits, in recent years, Chinese enterprises such as Jiangxi Saiwei, Luoyang Zhongsi, Sichuan Emei and Xinguang silicon have entered the polysilicon material industry on a large scale, with an estimated total investment of nearly 40billion yuan. After completion, an annual production capacity of 70000 tons can be formed. With the development of technology, the silicon consumption per watt of battery has also decreased by 5% annually from 12g/w in 2005, and will reach 9% in 2010. 3g/w, the goal of the industry is to reduce the silicon consumption to 6G/W. In addition, the rapid development of thin-film batteries will further alleviate the supply situation of polysilicon silicon materials

II. Pull rod and slice

polycrystalline silicon material needs to be transformed into monocrystalline silicon rod or polycrystalline ingot before it can be further processed into silicon wafer, battery and components. The most commonly used process for monocrystalline silicon rod production is direct drawing. In this process, the polysilicon material is put into the quartz crucible, heated and slowly melted, immersed in a seed crystal with a certain crystal orientation, and the growth process of a single crystal is completed through necking, shoulder laying, shoulder rotation, equal diameter, ending growth and cooling. The most commonly used process for the production of polycrystalline ingots is ingot casting. In this process, polycrystalline silicon is put into a quartz crucible and is heated, melted, grown, annealed and cooled to complete the growth process of a polycrystalline ingot. At present, multi wire cutting technology is basically used to cut monocrystalline silicon rods or polycrystalline anchors into silicon wafers. Silicon rods or ingots are processed into silicon wafers that meet specific requirements through surface shaping, orientation, cutting, grinding, corrosion, polishing, cleaning and other processes. The thickness of silicon wafer has developed from the mainstream thickness of 270um in 2004 to the current thickness of 200um. At present, the thickness of silicon wafers produced by some international manufacturers can reach 180um. After about two years of development, the utilization rate of silicon wafer has increased by more than 32%. As the crystal drawing furnace and the crystal casting furnace are relatively cheap, and have basically achieved localization, coupled with the low technical threshold, a large number of rod drawing and slicing projects have been launched in China in recent years. However, the bottleneck factors of polysilicon materials often make these silicon rod, ingot and wafer enterprises into an embarrassing situation

III. crystalline silicon battery

the next step in rod slicing is the production of solar cells, which are divided into two categories: crystalline silicon cells and thin film coated cells. Crystalline silicon cells account for 93% of the market share, of which monocrystalline silicon cells have the highest conversion efficiency, which has reached 17% in China. 6%。 The conversion rate of polysilicon battery also exceeded 16%. Manufacturing solar crystalline silicon cells requires a lot of processes, including silicon wafer cleaning, surface flocking, diffusion bonding, dephosphorized silicon glass, plasma etching, plating minus reflection to check whether there is uneven clamping pressure, film shooting and wire printing. Due to the demand pull of the European market, especially the German market, domestic enterprises have made large-scale investment in this field in recent years. At present, there are 60 battery production enterprises in China, with a production capacity of 3200 MW, and the total scale of battery is among the world's leading. Up to now, a total of 10 companies in China's photovoltaic industry, including Wuxi Suntech, Trinasolar, Hebei Jingao, Tianwei Yingli, Nanjing CLP, Jiangxi Savi, Lin yangxinneng and Zhejiang Yuhui, have been listed overseas one after another. The total amount of IPO Financing exceeded $1.9 billion in the development process from imitation to independent renovation, with a total market value of 178. US $6.5 billion, with an average p/E ratio of 49 per enterprise. 47。 Different from the traditional centralized power generation and power supply mode, solar cells have the characteristics of portability and discreteness, which are easier and more suitable to be embedded in consumer terminals, which provides a broad market space for the application of solar cells. Although the battery is growing at a rate of more than 30% every year, and the current price is also rising steadily, which has become a hot spot of investment at home and abroad, investors have to carefully consider the problems of international teams, high investment and polysilicon material supply