There is a long way to go for the commercialization of concentrating to reduce the cost of photovoltaic power generation. The high cost of power generation has always been the biggest obstacle to the promotion of photovoltaic power generation. People try to solve the cost problem from many aspects, such as raw materials, production process and even operation scale. Researchers found that in addition to the above factors, the proportion of battery cost in the total cost of photovoltaic system can also be reduced by reducing the demand for solar cells. Under the guidance of this idea, concentrated photovoltaic technology began to emerge
concentrating technology helps reduce costs
multi junction I-V compound cells are the mainstream
concentrating technology has greatly reduced the demand for semiconductor materials
the so-called concentrating photovoltaic (CPV) technology, in short, is to magnify the received solar energy hundreds of times through a lens, and then focus the amplified energy on the photovoltaic cells with high efficiency and small area. Its basic principle is the same as that of lighting a match with a magnifying glass. However, because a lot of heat will be accumulated on the surface area of the battery after focusing, the traditional crystalline silicon solar cells with poor heat dissipation effect are not suitable for concentrating cells, especially high-power concentrating cells
concentrating photovoltaic technology adopts multi junction III-V compound cells. Sunyanzheng, general manager of Tianjin Lantian Solar Technology Co., Ltd., said in an interview that compared with crystalline silicon and thin-film battery technology, multi junction battery has many advantages. Firstly, the multi junction battery has the characteristics of wide spectral absorption, which greatly improves the conversion efficiency; Secondly, the multi junction battery has a small temperature coefficient, which is suitable for working at high temperature, so the high-power focusing technology can be used to reduce the battery area; In addition, replacing expensive semiconductor materials with relatively cheap condensing devices can effectively reduce costs and production energy consumption when applied to power generation on a large scale. It is understood that the theoretical conversion efficiency of crystalline silicon solar cells is about 26%, and the theoretical conversion rate of multi junction III-V cells can exceed 60%, which fully reflects the advantages of its wide spectrum absorption devices
for multi junction batteries, the conversion efficiency can be increased from 30% to more than 38% after focusing. Yurongwen, technical director of the solar business department of San'an optoelectronics Co., Ltd., told that the increase in the focusing ratio will also save the materials of solar cell chips, thereby reducing the cost. If polydsm high-performance polyamide of multi junction battery perfectly balances toughness and rigidity, and the light multiple is 1000 times, the required chip area is only 1/1000 of the light receiving area. It is estimated that for a pair of machines, we are now launching machines, and now we are buying mobile megawatt multi junction concentrating solar power plants that are sent for commissioning or freight, and the multi junction semiconductor materials used are only 67 grams
will coexist with traditional photovoltaic technology
the global concentrated photovoltaic market has high growth potential
the application of concentrated photovoltaic in China has begun
although the research and development history of concentrated photovoltaic technology has been more than 30 years, the commercial operation of concentrated photovoltaic power stations is still in its infancy worldwide; In China, many enterprises have begun to try to achieve breakthroughs in this field. It is understood that Chengdu Zhongshun Technology Co., Ltd., a subsidiary of Sichuan Hanlong group, has built concentrating photovoltaic power stations in Chongqing and Xichang; The demonstration power station with a scale of 1 MW, independently designed and installed by Xiamen San'an Optoelectronics in Golmud, Qinghai Province, has also completed the overall equipment installation
in terms of battery R & D and industrialization, the products of most enterprises in China's aerospace system and electronic technology system are concentrated in the low-end, and many research institutes are also committed to the R & D and production of concentrated solar cell chips. The attractive industrial prospects also prompted local governments to increase their support for enterprises. In June this year, the people's Government of Shuangliu County, Chengdu, Sichuan Province signed a contract with Sichuan Hanlong group and Zhongshun solar energy development Co., Ltd. to build the world's first solar concentrating photovoltaic industrial park. The project plans to build a production scale of 2million kW within two years
the concentrated photovoltaic market has high growth potential. According to sunyanzheng, the current installed capacity of the global concentrating photovoltaic system is less than 200MW. It is expected that in the next few years, with the embodiment of technical advantages and cost advantages, the market scale will grow explosively. In the next 10 years, the average annual growth rate of global concentrated photovoltaic is expected to be more than 40%, and the total output value of the industry will reach about 50billion yuan by 2020. At present, there are only a few demonstration power stations in China. With the increase of photovoltaic installed capacity, the market of concentrated photovoltaic will gradually open. Sun Yanzheng said
however, in the long run, concentrated photovoltaic systems will not and cannot completely replace the market of crystalline silicon and thin-film batteries. Sunyanzheng said that the concentrating photovoltaic system is suitable for large-scale photovoltaic power stations, while crystalline silicon and thin-film cells are not only suitable for large-scale photovoltaic power stations, but also suitable for smaller household, commercial and building integrated power generation systems
system engineering needs to break through difficulties
solar tracking system requires higher accuracy
environmental impact cannot be ignored
however, the technical threshold of concentrating photovoltaic system is high, its solar cell production technology is complex, system integration technology is complex, and its core technology triple junction gallium arsenide cell epitaxy technology is only mastered by a few manufacturers, so there is still a long way to go to truly realize commercialization
in terms of cost, the cost of solar tracking system and maintenance guarantee system of CPV can not be ignored. Li Hongbo, director of Shanghai Solar Energy Engineering Technology Research Center, said in an interview with China Electronics News that although ordinary crystalline silicon photovoltaic systems also need tracking systems, high-power concentrating photovoltaic solar tracking systems require very high accuracy, on the one hand, to ensure that solar energy can accurately focus on solar cell chips, on the other hand, to avoid damage to the component materials around the chips; The improvement of the accuracy of the sun tracking system will also greatly increase the cost. In addition, the surrounding environment also has a great impact on the concentrating photovoltaic system. For example, when the wind blows, a small tilt has little impact on the crystalline silicon cell, but it is likely to have a fatal impact on the concentrating effect of the concentrating photovoltaic system
according to Li Hongbo, Shanghai Solar Energy Engineering Technology Research Center has completed a 1 kW concentrated photovoltaic demonstration project, which has been running for two years, and is currently building a 50 kW demonstration project. It should be said that during the operation of the demonstration project, we have solved many problems, but many new problems have emerged in succession, which need us to solve. Li Hongbo said
enterprise view
sunyanzheng, general manager of Tianjin Lantian Solar Technology Co., Ltd.
CPV has the most cost advantage
CPV power generation technology is gradually becoming the focus of the solar field. The traditional photovoltaic power generation technology screw load meter (ammeter or voltmeter) can correctly reflect the extrusion pressure, mainly including crystalline silicon cell technology and thin film cell technology. Concentrating photovoltaic industry is a new power generation industry
the production process of concentrating photovoltaic system is more energy-saving and environmental friendly. Compared with the traditional manufacturing process of crystalline silicon battery, it has the characteristics of low pollution and low energy consumption. The larger the condensing multiple of the system, the smaller the area of photovoltaic cells required. For a 500 times condensing photovoltaic system, the electric energy that a battery with an area of 10mm and 10mm can generate is equivalent to that of a battery with an area of 230mm and 230mm. While saving the amount of semiconductor materials, it reduces the production cost and energy consumption of the solar power generation system, making the concentrating photovoltaic system have a shorter energy recovery period
concentrated photovoltaic power generation has more room for cost reduction. With the maturity of concentrating photovoltaic technology and the further expansion of production scale, its comprehensive cost is expected to be lower than that of crystalline silicon and thin film cells in the next few years. If the carbon emission tax is levied on the production of photovoltaic power generation equipment, the payback period of the concentrated photovoltaic system will only be extended by 1 ~ 2 months, while the crystalline silicon and thin-film cells will be extended by more than 1 year. At that time, the relative cost advantage of the concentrated photovoltaic system will be more obvious
LINK
Copyright © 2011 JIN SHI