Solar energy is an inexhaustible renewable energy source for human beings. There are huge reserves, no exhaustion, no geographical restrictions, clean and renewable advantages. The research and application of solar energy plays an important role in the long-term energy strategy. It is one of the main directions of human energy development and has received the attention of all countries in the world. At present, China's industrial development momentum is rapid, but China's main energy source It is still coal and oil, and the pollution is serious. Some industrial cities in China have also become the world. The most polluted city. Therefore, vigorously developing solar energy is China’s It is imperative. "Renewable Energy of the People's Republic of China" from January 1, 2006 The implementation of the Law will further promote the development and utilization of renewable energy. This move It will greatly promote the research progress of solar energy as a clean renewable energy source. There are three main types of technologies for solar energy development and utilization, namely, solar lighting, Thermal energy utilization, photovoltaic power generation. In 1959, China made the first solar photovoltaic Since the battery, solar photovoltaic applications have evolved from simple lighting to aerospace and communication. In the fields of communications, oil, transportation, power and defense. This article mainly introduces recent years The development of solar power technology, and the application of solar power technology in China And outlook. 1 Development of solar cell technology The development of solar cell technology discovered from 1800 Berkeley The effect began, and then in 1876 the British scientist Adams et al. Effect study, until 1954, the United States Bell Labs used silicon crystal materials Produced a good performance solar cell, which has been continuously improved to become silicon The prototype of a solar cell. With the development of aerospace technology, the solar cell The role is irreplaceable, solar cells become irreplaceable in space vehicles important part. For the first time on the US Vanguard 1 launched in March 1958 Solar cells are installed. The 3rd man-made launched by the Soviet Union in May 1958 Solar cells have also begun to be installed on satellites. Since then, almost all launched man-made Solar cells are installed on the celestial bodies. "Energy that appeared in the early 1970s The source crisis, let people begin to realize that they cannot rely on traditional energy sources for a long time. The application of solar cells has been put on the agenda of governments. 1990 After the year, solar cells have been developed with new structures and manufacturing techniques. Come.
1.1 Solar battery generator Solar cells use electricity and materials to directly generate electricity. Capable device. There are many kinds of materials that can produce photovoltaic effects, such as: silicon-based materials. (monocrystalline silicon, polycrystalline silicon, amorphous silicon), compound semiconductor (gallium arsenide, selenium indium copper) Wait. Their power generation principles are basically the same. How does this type of solar cell work? Is a photovoltaic-based effect of P-N junctions: when N-type semiconductors and P-type semiconductors When the bodies are combined together by appropriate methods, they form at the junction of the two The P-N junction. Due to the diffusion of majority carriers, a space charge region is formed, and Forming an ever-increasing built-in from n-type semiconductor to p-type semiconductor The electric field causes the majority carriers to drift in the opposite direction. After reaching equilibrium, the diffusion Current and drift produce equal current. If the light is on the p–n junction and the light Can be larger than the forbidden band width of the p–n junction, and electrons will be generated near the p–n junction— Hole pair. Due to the presence of built-in electric fields, the resulting unbalanced electron carriers will Drifting to both ends of the space charge region, generating a photo-generated potential, destroying the original flat Balance. If the p–n junction is connected to an external circuit, current is present in the circuit. The current generation process will vary depending on the material. Head The theoretical research of pre-inorganic semiconductors is relatively mature, and the electricity of organic semiconductor systems There are still many places worth exploring in the flow generation process, which is the current research hotspot. 1.2 Solar cell materials Solar photovoltaic materials are an important class of semiconductor materials with semiconductors The nature of the bulk material. In principle, all semiconductor materials have photovoltaic effects. Should be used for the basic materials of solar cells. But due to material physics Limits on nature, purification preparation techniques, and cost, real application to the sun There are not many semiconductors in the battery industry. Since the discovery of the photovoltaic effect in 1800, the development of solar cell materials The process can be divided into the following three stages: First generation solar cells: including monocrystalline silicon solar cells and polysilicon too Yang battery. From 1954, the invention of monocrystalline silicon solar cells began to the present, Tube silicon materials have various problems, but they are still the main materials of current solar cells. It accounts for more than 90% of the total solar cell production. Beijing, China, solar energy The Institute began research on high-efficiency batteries from the 1990s. Inverted pyramid surface texture, emitter passivation, back field and other technologies to make single crystal silicon The efficiency of the solar cell reached 19.8%. Second generation solar cells: second generation solar cells are based on thin film materials Solar battery. Thin film technology requires less material than crystalline silicon solar cells Many, and easy to achieve large-area battery production, is an effective cost reduction method. Thin film batteries mainly include amorphous silicon thin film batteries and polycrystalline silicon thin film batteries. Cadmium telluride and copper indium selenide thin film batteries. Nankai University of China in the 20th century At the end of the decade, he began to study copper indium selenide thin film batteries, which are currently in the field of research. Leading domestic and international advanced position. The efficiency of the prepared copper indium selenide solar cell More than 12%, the pilot production line of copper indium selenide thin film solar cells has also been built. to make. China's scientific research and industry in dye-sensitized nano-film solar cells The research is close to the level of world research. In dye sensitizer, nano thin Membrane modification and battery photoelectric efficiency have achieved scientific research water close to the world Ping has a certain influence in this field. Research progress and application of solar cells □ Zhou Chuanhua Chen Wei (School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China) Abstract: As a solar energy for clean renewable energy, more and more research is being carried out. The paper briefly introduces the generator of solar cells. The three development stages of solar cell materials outline the current status and problems of China's solar power technology industry, and look forward to China's solar power technology. Future trends. Keywords: solar cell application review CLC number: TK51 Document code: A Article ID: 1007-3973 (2008) 08-047-02 48 Association for Science and Technology Forum · No. 8 (2008) Science and research Third-generation solar cells: Ma rtin Green believes that the third generation of solar power The pool must have the following conditions: thin film formation, high conversion efficiency, rich raw materials and no poison. At present, the third generation of solar cells is still undergoing conceptual and simple experimental research. The third generation of solar cells that have been proposed mainly include laminated solar cells and multiple band gaps. Solar cells and hot carrier solar cells. Although the research on solar cell materials has reached the third stage, In the maturity and manufacturing cost of process technology, it has not been possible in recent years. It is comparable to conventional silicon solar cells. Silicon solar cells are manufactured After several decades of hard work, this has finally been greatly reduced, but there are often Compared with energy, it is still relatively expensive, which limits its further large scale. application. In view of this, the development of low-cost, high-efficiency solar cell materials is still However, there is a long way to go. 2 Application Status of Solar Power Technology in China 2.1 China's solar power development In 1958, China began to develop solar cells. In 1959, the first one was real. The use of solar cells of value (developed by the Institute of Semiconductors, Chinese Academy of Sciences). 1971 In March of the year, solar cells were first applied to China's second artificial satellite practice 1 No. (developed by Tianjin Power Supply), the first application of solar cells in 1973 On the buoy light of Tianjin Port (developed by Tianjin Power), in the 1980s In the later period, China introduced foreign key equipment or complete sets of production lines and solar cells. Production technology, the solar cell manufacturing industry has taken shape. 2.2 China's solar power application With the advancement of technology and the expansion of application scale, solar photovoltaic power generation In addition to being a power source for spacecraft, the range of applications on the ground is gradually Remote rural areas and special electricity use have developed into urban areas. In order to accelerate the development of solar power in China, since 1997, the world Banks invest US$27 million in solar energy development in China, of which 2550 Ten thousand dollars is used for photovoltaic power generation projects and the development of solar energy technology. After the section With three years of hard work, there are about 90,000 households in six poverty-stricken areas in western China. Residents used solar power. At present, China's solar photovoltaic power generation application Mainly for independent photovoltaic power generation in rural electrification and communication and industrial power supply System, and there are some photovoltaic and building integrated systems and desert photovoltaic power plants. China's current solar photovoltaic industry mainly plays in the following aspects Use: First, national demonstration projects, popular projects and international cooperation projects, such as "West Construction of projects such as “Building a county without electricity”, “Power transmission to the township”, and “Guangming project”; In addition, it is the communication and reception of satellite signals, and the transmission and reception of satellite signals. Power supply for systems such as cathodic protection of oil and gas pipelines; Streetlights, solar electric vehicles, billboards, lawn lights, etc. source. For example, 80%-90% of street lamps around the 2008 Beijing Olympic venues are used. Solar photovoltaic technology generates electricity. In addition, other applications are still compared less. 2.3 Problems in China's solar power generation technology China's solar power technology lags behind Germany, Japan, the United States, and Australia Developed countries such as Lia, even behind India. China's solar energy cannot be ignored The abnormal state of the industry: more than 90% of the raw materials depend on imports, more than 90% The export of products, a typical two-headed industry. As solar photovoltaic The main raw material of the pool, 95% of China's high-purity polysilicon materials rely on imports, and And the technology is basically monopolized by foreign countries. This problem has become the development of China. The biggest bottleneck in the solar energy industry. In addition, although China has promulgated the "Renewable Energy Law," the law clearly mentions "The state encourages units and individuals to install and use solar photovoltaic systems. "Organization of solar energy utilization systems", but corresponding operational measures, such as The grid price method has not been introduced yet. At present, the grid company only accepts wind power and raw Material power generation. The production of solar photovoltaic cells and raw material polysilicon is high pollution Dyeing, high energy consumption industry, plus China does not master the key technology of polysilicon production Surgery, excessive cost and cost of pollution energy also limit solar power technology The development of surgery. 3 Prospects Although compared with the international advanced level, China's solar power technology still There is a big gap. China's solar power industry still has this or Such a problem, but as a solar energy for clean renewable energy, because of its independence Special advantages and broad application prospects, coupled with the strong support of the Chinese government, Will definitely break through the bottleneck. It is currently to be strengthened in the following areas: (1) Study the technology of polysilicon production, break through the technical bottleneck and reduce production Energy consumption and pollution problems in the polysilicon process. (2) Intensify the introduction of the "On-grid Electricity Price Law" to accept solar power generation and introduce Practical incentives and incentives to further accelerate the development of solar power technology step. (3) Accelerate research on solar cell materials and develop high conversion rates and low New materials for cost. In the years to come, the solar power industry has become a big producer. The industry will provide a lot of employment opportunities, and more people will be engaged in solar power technology. Research and production. Solar photovoltaic power generation will become the pillar of China's energy One of the industries. At the same time, it will drive the rapid development of related industries.