1. Polysilicon industry chain: The production process is complex, and the downstream focuses on photovoltaic semiconductors
Polysilicon is mainly produced from industrial silicon, chlorine and hydrogen, and is located upstream of the photovoltaic and semiconductor industry chains. According to CPIA data, the current mainstream polysilicon production method in the world is the modified Siemens method, except for China, more than 95% of the polysilicon is produced by the modified Siemens method. In the process of preparing polysilicon by the improved Siemens method, firstly, chlorine gas is combined with hydrogen gas to generate hydrogen chloride, and then it reacts with the silicon powder after crushing and grinding of industrial silicon to generate trichlorosilane, which is further reduced by hydrogen gas to generate polysilicon. Polycrystalline silicon can be melted and cooled to make polycrystalline silicon ingots, and monocrystalline silicon can also be produced by Czochralski or zone melting. Compared with polycrystalline silicon, single crystal silicon is composed of crystal grains with the same crystal orientation, so it has better electrical conductivity and conversion efficiency. Both polycrystalline silicon ingots and monocrystalline silicon rods can be further cut and processed into silicon wafers and cells, which in turn become key parts of photovoltaic modules and are used in the photovoltaic field. In addition, single crystal silicon wafers can also be formed into silicon wafers by repeated grinding, polishing, epitaxy, cleaning and other processes, which can be used as substrate materials for semiconductor electronic devices.
The polysilicon impurity content is strictly required, and the industry has the characteristics of high capital investment and high technical barriers. Since the purity of polysilicon will seriously affect the single crystal silicon drawing process, the purity requirements are extremely strict. The minimum purity of polysilicon is 99.9999%, and the highest is infinitely close to 100%. In addition, China's national standards put forward clear requirements for impurity content, and based on this, polysilicon is divided into grades I, II, and III, of which the content of boron, phosphorus, oxygen and carbon is an important reference index. "Polysilicon Industry Access Conditions" stipulates that enterprises must have a sound quality inspection and management system, and product standards strictly comply with national standards; in addition, the access conditions also require the scale and energy consumption of polysilicon production enterprises, such as solar-grade, electronic-grade polysilicon The project scale is greater than 3000 tons/year and 1000 tons/year respectively, and the minimum capital ratio in the investment of new construction and reconstruction and expansion projects shall not be lower than 30%, so polysilicon is a capital-intensive industry. According to CPIA statistics, the investment cost of 10,000-ton polysilicon production line equipment put into operation in 2021 has slightly increased to 103 million yuan/kt. The reason is the rise in the price of bulk metal materials. It is expected that the investment cost in the future will increase with the progress of production equipment technology and monomer decrease as the size increases. According to the regulations, the power consumption of polysilicon for solar-grade and electronic-grade Czochralski reduction should be less than 60 kWh/kg and 100 kWh/kg respectively, and the requirements for energy consumption indicators are relatively strict. Polysilicon production tends to belong to the chemical industry. The production process is relatively complex, and the threshold for technical routes, equipment selection, commissioning and operation is high. The production process involves many complex chemical reactions, and the number of control nodes is more than 1,000. It is difficult for new entrants Quickly master mature craftsmanship. Therefore, there are high capital and technical barriers in the polysilicon production industry, which also promotes polysilicon manufacturers to carry out strict technical optimization of the process flow, packaging and transportation process.
2. Polysilicon classification: purity determines use, and solar grade occupies the mainstream
Polycrystalline silicon, a form of elemental silicon, is composed of crystal grains with different crystal orientations, and is mainly purified by industrial silicon processing. The appearance of polysilicon is gray metallic luster, and the melting point is about 1410℃. It is inactive at room temperature and more active in the molten state. Polysilicon has semiconductor properties and is an extremely important and excellent semiconductor material, but a small amount of impurities can greatly affect its conductivity. There are many classification methods for polysilicon. In addition to the above-mentioned classification according to China's national standards, three more important classification methods are introduced here. According to different purity requirements and uses, polysilicon can be divided into solar-grade polysilicon and electronic-grade polysilicon. Solar-grade polysilicon is mainly used in the production of photovoltaic cells, while electronic-grade polysilicon is widely used in the integrated circuit industry as a raw material for chips and other production. The purity of solar-grade polysilicon is 6~8N, that is, the total impurity content is required to be lower than 10 -6, and the purity of polysilicon must reach 99.9999% or more. The purity requirements of electronic-grade polysilicon are more stringent, with a minimum of 9N and a current maximum of 12N. The production of electronic-grade polysilicon is relatively difficult. There are few Chinese enterprises that have mastered the production technology of electronic-grade polysilicon, and they are still relatively dependent on imports. At present, the output of solar-grade polysilicon is much larger than that of electronic-grade polysilicon, and the former is about 13.8 times that of the latter.
According to the difference of doping impurities and conductivity type of silicon material, it can be divided into P-type and N-type. When silicon is doped with acceptor impurity elements, such as boron, aluminum, gallium, etc., it is dominated by hole conduction and is P-type. When silicon is doped with donor impurity elements, such as phosphorus, arsenic, antimony, etc., it is dominated by electron conduction and is N-type. P-type batteries mainly include BSF batteries and PERC batteries. In 2021, PERC batteries will account for more than 91% of the global market, and BSF batteries will be eliminated. During the period when PERC replaces BSF, the conversion efficiency of P-type cells has increased from less than 20% to more than 23%, which is about to approach the theoretical upper limit of 24.5%, while the theoretical upper limit of N-type cells is 28.7%, and N-type cells have high conversion efficiency, Due to the advantages of high bifacial ratio and low temperature coefficient, companies have begun to deploy mass production lines for N-type batteries. According to CPIA's forecast, the proportion of N-type batteries will increase significantly from 3% to 13.4% in 2022. It is expected that in the next five years, the iteration of N-type battery to P-type battery will be ushered in. According to the different surface quality, it can be divided into dense material, cauliflower material and coral material. The surface of the dense material has the lowest degree of concavity, less than 5mm, no color abnormality, no oxidation interlayer, and the highest price; the surface of the cauliflower material has a moderate degree of concavity, 5-20mm, the section is moderate, and the price is mid-range; while the surface of the coral material has more serious concavity, The depth is greater than 20mm, the section is loose, and the price is the lowest. The dense material is mainly used to draw monocrystalline silicon, while the cauliflower material and coral material are mainly used to make polycrystalline silicon wafers. In the daily production of enterprises, the dense material can be doped with no less than 30% cauliflower material to produce monocrystalline silicon. The cost of raw materials can be saved, but the use of cauliflower material will reduce the crystal pulling efficiency to a certain extent. Enterprises need to choose the appropriate doping ratio after weighing the two. Recently, the price difference between dense material and cauliflower material has basically stabilized at 3 RMB /kg. If the price difference is further widened, companies may consider doping more cauliflower material in monocrystalline silicon pulling.
3. Process: Siemens method occupies the mainstream, and power consumption becomes the key to technological change
The production process of polysilicon is roughly divided into two steps. In the first step, industrial silicon powder is reacted with anhydrous hydrogen chloride to obtain trichlorosilane and hydrogen. After repeated distillation and purification, gaseous trichlorosilane, dichlorodihydrosilicon and Silane; the second step is to reduce the above-mentioned high-purity gas to crystalline silicon, and the reduction step is different in the modified Siemens method and the silane fluidized bed method. The improved Siemens method has mature production technology and high product quality, and is currently the most widely used production technology. The traditional Siemens production method is to use chlorine and hydrogen to synthesize anhydrous hydrogen chloride, hydrogen chloride and powdered industrial silicon to synthesize trichlorosilane at a certain temperature, and then separate, rectify and purify the trichlorosilane. The silicon undergoes a thermal reduction reaction in a hydrogen reduction furnace to obtain elemental silicon deposited on the silicon core. On this basis, the improved Siemens process is also equipped with a supporting process for recycling a large amount of by-products such as hydrogen, hydrogen chloride, and silicon tetrachloride produced in the production process, mainly including reduction tail gas recovery and silicon tetrachloride reuse technology. Hydrogen, hydrogen chloride, trichlorosilane, and silicon tetrachloride in the exhaust gas are separated by dry recovery. Hydrogen and hydrogen chloride can be reused for synthesis and purification with trichlorosilane, and trichlorosilane is directly recycled into thermal reduction. Purification is carried out in the furnace, and silicon tetrachloride is hydrogenated to produce trichlorosilane, which can be used for purification. This step is also called cold hydrogenation treatment. By realizing closed-circuit production, enterprises can significantly reduce the consumption of raw materials and electricity, thereby effectively saving production costs.
The cost of producing polysilicon using the improved Siemens method in China includes raw materials, energy consumption, depreciation, processing costs, etc. The technological progress in the industry has significantly driven down the cost. The raw materials mainly refer to industrial silicon and trichlorosilane, the energy consumption includes electricity and steam, and the processing costs refer to the inspection and repair costs of production equipment. According to Baichuan Yingfu's statistics on polysilicon production costs in early June 2022, raw materials are the highest cost item, accounting for 41% of the total cost, of which industrial silicon is the main source of silicon. The silicon unit consumption commonly used in the industry represents the amount of silicon consumed per unit of high-purity silicon products. The calculation method is to convert all silicon-containing materials such as outsourced industrial silicon powder and trichlorosilane into pure silicon, and then deduct the outsourced chlorosilane as per The amount of pure silicon converted from the silicon content ratio. According to CPIA data, the level of silicon consumption will drop by 0.01 kg/kg-Si to 1.09 kg/kg-Si in 2021. It is expected that with the improvement of cold hydrogenation treatment and by-product recycling, it is expected to decrease to 1.07 kg/kg by 2030. kg-Si. According to incomplete statistics, the silicon consumption of the top five Chinese companies in the polysilicon industry is lower than the industry average. It is known that two of them will consume 1.08 kg/kg-Si and 1.05 kg/kg-Si respectively in 2021. The second highest proportion is energy consumption, accounting for 32% in total, of which electricity accounts for 30% of the total cost, indicating that electricity price and efficiency are still important factors for polysilicon production. The two major indicators to measure the power efficiency are comprehensive power consumption and reduction power consumption. The reduction power consumption refers to the process of reducing trichlorosilane and hydrogen to generate high-purity silicon material. The power consumption includes silicon core preheating and deposition. , heat preservation, end ventilation and other process power consumption. In 2021, with technological progress and comprehensive utilization of energy, the average comprehensive power consumption of polysilicon production will decrease by 5.3% year-on-year to 63kWh/kg-Si, and the average reduction power consumption will decrease by 6.1% year-on-year to 46kWh/kg-Si, which is expected to decrease further in the future. . In addition, depreciation is also an important item of cost, accounting for 17%. It is worth noting that, according to Baichuan Yingfu data, the total production cost of polysilicon in early June 2022 was about 55,816 yuan/ton, the average price of polysilicon in the market was about 260,000 yuan/ton, and the gross profit margin was as high as 70% or more, so it attracted a large number of Enterprises invest in the construction of polysilicon production capacity.
There are two ways for polysilicon manufacturers to reduce costs, one is to reduce raw material costs, and the other is to reduce power consumption. In terms of raw materials, manufacturers can reduce the cost of raw materials by signing long-term cooperation agreements with industrial silicon manufacturers, or building integrated upstream and downstream production capacity. For example, polysilicon production plants basically rely on their own industrial silicon supply. In terms of electricity consumption, manufacturers can reduce electricity costs by means of low electricity prices and comprehensive energy consumption improvement. About 70% of the comprehensive electricity consumption is reduction electricity consumption, and reduction is also a key link in the production of high-purity crystalline silicon. Therefore, most polysilicon production capacity in China is concentrated in regions with low electricity prices such as Xinjiang, Inner Mongolia, Sichuan and Yunnan. However, with the advancement of the two-carbon policy, it is difficult to obtain a large amount of low-cost power resources. Therefore, reducing power consumption for reduction is a more feasible cost reduction today. Way. At present, the effective way to reduce reduction power consumption is to increase the number of silicon cores in the reduction furnace, thereby expanding the output of a single unit. At present, the mainstream reduction furnace types in China are 36 pairs of rods, 40 pairs of rods and 48 pairs of rods. The furnace type is upgraded to 60 pairs of rods and 72 pairs of rods, but at the same time, it also puts forward higher requirements for the production technology level of enterprises.
Compared with the improved Siemens method, the silane fluidized bed method has three advantages, one is low power consumption, the other is high crystal pulling output, and the third is that it is more favorable to combine with the more advanced CCZ continuous Czochralski technology. According to the data of the Silicon Industry Branch, the comprehensive power consumption of the silane fluidized bed method is 33.33% of the improved Siemens method, and the reduction power consumption is 10% of the improved Siemens method. The silane fluidized bed method has significant energy consumption advantages. In terms of crystal pulling, the physical properties of granular silicon can make it easier to fully fill the quartz crucible in the single crystal silicon pulling rod link. Polycrystalline silicon and granular silicon can increase the single furnace crucible charging capacity by 29%, while reducing the charging time by 41%, significantly improving the pulling efficiency of single crystal silicon. In addition, granular silicon has a small diameter and good fluidity, which is more suitable for the CCZ continuous Czochralski method. At present, the main technology of single crystal pulling in the middle and lower reaches is the RCZ single crystal re-casting method, which is to re-feed and pull the crystal after a single crystal silicon rod is pulled. The drawing is carried out at the same time, which saves the cooling time of the single crystal silicon rod, so the production efficiency is higher. The rapid development of the CCZ continuous Czochralski method will also drive up the demand for granular silicon. Although granular silicon has some disadvantages, such as more silicon powder generated by friction, large surface area and easy adsorption of pollutants, and hydrogen combined into hydrogen during melting, which is easy to cause skipping, but according to the latest announcements of relevant granular silicon enterprises, these problems are being improved and Some progress has been made.
silane fluidized bed process is mature in Europe and the United States, and it is in its infancy after the introduction of Chinese enterprises. As early as the 1980s, foreign granular silicon represented by REC and MEMC began to explore the production of granular silicon and realized large-scale production. Among them, REC's total production capacity of granular silicon reached 10,500 tons/year in 2010, and compared with its Siemens counterparts in the same period, it had a cost advantage of at least US$2-3/kg. Due to the needs of single crystal pulling, the company's granular silicon production stagnated and eventually stopped production, and turned to a joint venture with China to establish a production enterprise to engage in the production of granular silicon.
4. Raw materials: Industrial silicon is the core raw material, and the supply can meet the needs of polysilicon expansion
Industrial silicon is the core raw material for polysilicon production. It is expected that China's industrial silicon output will grow steadily from 2022 to 2025. From 2010 to 2021, China's industrial silicon production is in the expansion stage, with the average annual growth rate of production capacity and output reaching 7.4% and 8.6%, respectively. According to SMM data, the newly increased industrial silicon production capacity in China will be 890,000 tons and 1.065 million tons in 2022 and 2023 . Assuming that industrial silicon companies will still maintain a capacity utilization rate and operating rate of about 60% in the future, China's newly increased production capacity in 2022 and 2023 will bring about an output increase of 320,000 tons and 383,000 tons. According to the estimates of GFCI, China's industrial silicon production capacity in 22/23/24/25 is about 5.90/697/6.71/6.5 million tons, corresponding to 3.55/391/4.18/4.38 million tons.
The growth rate of the remaining two downstream areas of superimposed industrial silicon is relatively slow, and China's industrial silicon production can basically meet the production of polysilicon. In 2021, China's industrial silicon production capacity will be 5.385 million tons, corresponding to an output of 3.213 million tons, of which polysilicon, organic silicon, and aluminum alloys will consume 623,000 tons, 898,000 tons, and 649,000 tons, respectively. In addition, nearly 780,000 tons of output are used for Export. In 2021, the consumption of polysilicon, organic silicon, and aluminum alloys will account for 19%, 28%, and 20% of industrial silicon, respectively. From 2022 to 2025, the growth rate of organic silicon production is expected to remain at around 10%, and the growth rate of aluminum alloy production is lower than 5%. Therefore, we believe that the amount of industrial silicon that can be used for polysilicon in 2022-2025 is relatively sufficient, which can fully meet the needs of polysilicon. production needs.
5. Polysilicon supply: China occupies a dominant position, and production gradually gathers to leading enterprises
In recent years, the global polysilicon production has increased year by year, and has gradually gathered in China . From 2017 to 2021, the global annual polysilicon production has risen from 432,000 tons to 631,000 tons, with the fastest growth in 2021, with a growth rate of 21.11%. During this period, global polysilicon production gradually concentrated in China , and the proportion of China's polysilicon production increased from 56.02% in 2017 to 80.03% in 2021. Comparing the top ten companies in the global polysilicon production capacity in 2010 and 2021, it can be found that the number of Chinese companies has increased from 4 to 8, and the proportion of production capacity of some American and Korean companies has dropped significantly, falling out of the top ten teams, such as HEMOLOCK , OCI, REC and MEMC; the industry concentration has increased significantly, and the total production capacity of the top ten companies in the industry has increased from 57.7% to 90.3%. In 2021, there are five Chinese companies that account for more than 10% of production capacity, accounting for a total of 65.7%. . There are three main reasons for the gradual transfer of the polysilicon industry to China . First, Chinese polysilicon manufacturers have significant advantages in terms of raw materials, electricity and labor costs. The wages of workers are lower than those of foreign countries, so the overall production cost in China is much lower than that of foreign countries, and will continue to decline with technological progress; second, the quality of Chinese polysilicon products is constantly improving, most of which are at the solar-grade first-class level, and individual advanced enterprises are in the purity requirements. Breakthroughs have been made in the production technology of higher electronic-grade polysilicon, gradually ushering in the substitution of domestic electronic-grade polysilicon for imports, and Chinese leading enterprises are actively promoting the construction of electronic-grade polysilicon projects. The production output of silicon wafers in China is more than 95% of the total global production output, which has gradually increased the self-sufficiency rate of polysilicon for China, which has squeezed the market of overseas polysilicon enterprises to a certain extent.
From 2017 to 2021, the annual output of polysilicon in China will increase steadily, mainly in areas rich in power resources such as Xinjiang, Inner Mongolia, and Sichuan. In 2021, China's polysilicon production will increase from 392,000 tons to 505,000 tons, an increase of 28.83%. In terms of production capacity, China's polysilicon production capacity has generally been on an upward trend, but it has declined in 2020 due to the shutdown of some manufacturers. In addition, the capacity utilization rate of Chinese polysilicon enterprises has been increasing continuously since 2018, and the capacity utilization rate in 2021 will reach 97.12%. In terms of provinces, China's polysilicon production in 2021 is mainly concentrated in areas with low electricity prices such as Xinjiang, Inner Mongolia, and Sichuan. Xinjiang's output is 270,400 tons, which is more than half of the total output in China.
China's polysilicon industry is characterized by a high degree of concentration, with a CR6 value of 77%, and there will be a further upward trend in the future. Polysilicon production is an industry with high capital and high technical barriers. The project construction and production cycle is usually two years or more. It is difficult for new manufacturers to enter the industry. Judging from the known planned expansion and new projects in the next three years, oligopolistic manufacturers in the industry will continue to expand their production capacity by virtue of their own technology and scale advantages, and their monopoly position will continue to rise.
It is estimated that China's polysilicon supply will usher in a large-scale growth from 2022 to 2025, and polysilicon production will reach 1.194 million tons in 2025, driving the expansion of global polysilicon production scale. In 2021, with the sharp rise in the price of polysilicon in China, major manufacturers have invested in the construction of new production lines, and at the same time attracted new manufacturers to join the industry. Since polysilicon projects will take at least one and a half to two years from construction to production, new construction in 2021 will be completed. The production capacity is generally put into production in the second half of 2022 and 2023. This is very consistent with the new project plans announced by major manufacturers at present. The new production capacity in 2022-2025 is mainly concentrated in 2022 and 2023. After that, as the supply and demand of polysilicon and the price gradually stabilize, the total production capacity in the industry will gradually stabilize. Down, that is, the growth rate of production capacity gradually decreases. In addition, the capacity utilization rate of polysilicon enterprises has remained at a high level in the past two years, but it will take time for the production capacity of new projects to ramp up, and it will take a process for new entrants to master the relevant preparation technology. Therefore, the capacity utilization rate of new polysilicon projects in the next few years will be low. From this, the polysilicon production in 2022-2025 can be predicted, and the polysilicon production in 2025 is expected to be about 1.194 million tons.
Concentration of overseas production capacity is relatively high, and the rate and speed of production increase in the next three years will not be as high as that of China. Overseas polysilicon production capacity is mainly concentrated in four leading companies, and the rest are mainly small production capacity. In terms of production capacity, Wacker Chem occupies half of the overseas polysilicon production capacity. Its factories in Germany and the United States have production capacities of 60,000 tons and 20,000 tons, respectively. The sharp expansion of global polysilicon production capacity in 2022 and beyond may bring about Concerned about oversupply, the company is still in a wait-and-see state and has not planned to add new production capacity. South Korean polysilicon giant OCI is gradually relocating its solar-grade polysilicon production line to Malaysia while retaining the original electronic-grade polysilicon production line in China, which is planned to reach 5,000 tons in 2022. OCI's production capacity in Malaysia will reach 27,000 tons and 30,000 tons in 2020 and 2021, achieving low energy consumption costs and evading China's high tariffs on polysilicon in the United States and South Korea. The company plans to produce 95,000 tons but the start date is unclear. It is expected to increase at the level of 5,000 tons per year in the next four years. The Norwegian company REC has two production bases in Washington state and Montana, USA, with an annual production capacity of 18,000 tons of solar-grade polysilicon and 2,000 tons of electronic-grade polysilicon. REC, which was in deep financial distress, chose to suspend production, and then stimulated by the boom in polysilicon prices in 2021, the company decided to restart production of 18,000 tons of projects in Washington state and 2,000 tons in Montana by the end of 2023, and can complete the ramp-up of production capacity in 2024. Hemlock is the largest polysilicon producer in the United States, specializing in high-purity electronic-grade polysilicon. The high-tech barriers to production make it difficult for the company's products to be replaced in the market. Combined with the fact that the company does not plan to build new projects within a few years, it is expected that the company's production capacity will be 2022-2025. The annual output remains at 18,000 tons. In addition, in 2021, the new production capacity of companies other than the above four companies will be 5,000 tons. Due to the lack of understanding of the production plans of all companies, it is assumed here that the new production capacity will be 5,000 tons per year from 2022 to 2025.
According to overseas production capacity, it is estimated that overseas polysilicon production in 2025 will be about 176,000 tons, assuming that the utilization rate of overseas polysilicon production capacity remains unchanged. After the price of polysilicon has risen sharply in 2021, Chinese companies have increased production and expanded production. In contrast, overseas companies are more cautious in their plans for new projects. This is because the dominance of the polysilicon industry is already in the control of China, and blindly increasing production may bring losses. From the cost side, energy consumption is the largest component of the cost of polysilicon, so the price of electricity is very important, and Xinjiang, Inner Mongolia, Sichuan and other regions have obvious advantages. From the demand side, as the direct downstream of polysilicon, China's silicon wafer production accounts for more than 99% of the world's total. The downstream industry of polysilicon is mainly concentrated in China . The price of polysilicon produced is low, the transportation cost is low, and the demand is fully guaranteed. Secondly, China has imposed relatively high anti-dumping tariffs on imports of solar-grade polysilicon from the United States and South Korea, which has greatly suppressed the consumption of polysilicon from the United States and South Korea . Be cautious in building new projects; in addition, in recent years, Chinese overseas polysilicon enterprises have been slow to develop due to the impact of tariffs, and some production lines have been reduced or even shut down, and their proportion in global production has been decreasing year by year, so they will not be comparable to the rise in polysilicon prices in 2021 as Chinese company's high profits, the financial conditions are not sufficient to support its rapid and large-scale expansion of production capacity.
Based on the respective forecasts of polysilicon production in China and overseas from 2022 to 2025, the predicted value of global polysilicon production can be summed up. It is estimated that the global polysilicon production in 2025 will reach 1.371 million tons. According to the forecast value of polysilicon production, China’s share of global proportion can be roughly obtained . It is expected that the share of China will gradually expand from 2022 to 2025, and it will exceed 87% in 2025.
6, Summary and Outlook
Polysilicon is located downstream of industrial silicon and upstream of the entire photovoltaic and semiconductor industry chain, and its status is very important. The photovoltaic industry chain is generally polysilicon-silicon wafer-cell-module-photovoltaic installed capacity, and the semiconductor industry chain is generally polysilicon-monocrystalline silicon wafer-silicon wafer-chip. Different uses have different requirements on the purity of polysilicon. The photovoltaic industry mainly uses solar-grade polysilicon, and the semiconductor industry uses electronic-grade polysilicon. The former has a purity range of 6N-8N, while the latter requires a purity of 9N or more.
For years, the mainstream production process of polysilicon has been the improved Siemens method all over the world. In recent years, some companies have actively explored the lower cost silane fluidized bed method, which may have an impact on the production pattern. The rod-shaped polysilicon produced by the modified Siemens method has the characteristics of high energy consumption, high cost and high purity, while the granular silicon produced by the silane fluidized bed method has the characteristics of low energy consumption, low cost and relatively low purity. Some Chinese companies have realized the mass production of granular silicon and the technology of using granular silicon to pull polysilicon, but it has not been widely promoted. Whether granular silicon can replace the former in the future depends on whether the cost advantage can cover the quality disadvantage, the effect of downstream applications, and the improvement of silane safety. In recent years, the global polysilicon production has increased year by year, and gradually gather together at China. From 2017 to 2021, the global annual polysilicon production will increase from 432,000 tons to 631,000 tons, with the fastest growth in 2021. During the period, global polysilicon production gradually became more and more concentrated to China, and China proportion of polysilicon production increased from 56.02% in 2017 to 80.03% in 2021. From 2022 to 2025, the supply of polysilicon will usher in a large-scale growth. It is estimated that the polysilicon production in 2025 will be 1.194 million tons in China, and the overseas production will reach 176,000 tons. Therefore, the global polysilicon production in 2025 will be about 1.37 million tons.
(This article is only for the reference of UrbanMines’customers and does not represent any investment advice）