1 Application classification of photovoltaic power generation system
The application field of solar photovoltaic power generation system is extremely wide. Solar cells are the main components of solar photovoltaic power generation systems, but they are often not the key components in terms of their applications. Whether in terms of technology, industry, or the market, solar cells and photovoltaic power generation systems are both closely connected and different concepts. Shows the relationship between solar cell development and manufacturing and photovoltaic power generation systems and their applications. In other words, the photovoltaic industry is not equal to the solar cell industry. Nowadays, when it comes to the photovoltaic industry, it often refers to the development and manufacturing of solar cells. In fact, the volume of photovoltaic power generation systems and their applications is not smaller than the former. This may be the main reason why China’s solar cell industry has developed extremely rapidly in recent years, most of the products are exported, and the domestic applications are not enough.
The application of solar photovoltaic power generation system can be divided into two categories: independent type and grid-connected type.
Stand-alone photovoltaic power generation system mainly has 4 aspects, namely ① the photovoltaic power generation system for rural electrification, including independent photovoltaic power stations (village power supply system), solar household systems, solar lighting, solar water pumps, etc.; ② communities, schools, hospitals, restaurants, hotels, hotels, shopping malls, etc. Photovoltaic systems for government office buildings, etc.; ③ Photovoltaic systems for communications and other industrial applications, including microwave relay stations, optical cable communication systems, etc.; satellite communications and satellite TV receiving systems; program-controlled telephone systems; railway and highway signal systems; lighthouses and navigation lights power supplies ; Meteorological, earthquake, hydrological observation systems of observatory stations and other photovoltaic power supplies; cathodic protection power supplies such as sluices and oil pipelines, as well as military communications, border guard posts, etc.; ④ photovoltaic products, such as solar street lights, garden lights, lawn lights: solar insecticidal lights, Solar water pumps; solar urban and rural landscape lighting projects, solar signal signs, solar advertising light boxes, popular science light boxes, etc.: solar chargers, solar calculators, watches, toys, etc.; sun hats, solar clothing; solar bicycles, electric cars, yachts, airplanes Wait.
Grid-connected photovoltaic system is mainly used for the integration of solar photovoltaic system and building integrated photovoltaic system (Building Intergrated Photovoltaic) that combines urban and rural areas with buildings, that is, a photovoltaic grid-connected system in which photovoltaic power generation system and building function and appearance are coordinated and organically combined. This type of application has become the mainstream of the photovoltaic application market. Currently, developed countries such as Europe and the United States account for more than 90% of the photovoltaic power generation market. In China, in addition to distributed grid-connected photovoltaic power generation systems, the construction of large-scale and super-large centralized photovoltaic power plants in desert areas is also developing rapidly.
2 Development Roadmap of Photovoltaic Applications
Photovoltaic power generation needs to be used on a large scale and developed into a major alternative energy source, and it is necessary to further reduce the system cost and improve efficiency. At present, China’s domestic system has reached the cost of less than 10 yuan per peak watt, the cost of electricity per kilowatt-hour is 0.6 to 0.8 yuan, and the energy recovery cycle for manufacturing solar cells is 1 to 2 years, which is close to the goal of parity.
Strictly speaking, the factors that affect the on-grid price include local solar resources, system efficiency and power generation, reliability, and other conditions such as grid quality, initial investment scale, operation and maintenance costs, loan proportional interest rates, taxes and profit levels. Among them, local solar energy resources, system efficiency and initial investment scale are the main factors affecting the feed-in tariff.
For the photovoltaic grid connected power generation system, it can be divided into two cases: the generation side and the user side. To achieve the grid on the power generation side, that is, for power generation companies, it must be close to the conventional on-grid power price, that is, the current electricity price is 0.33~0.36 yuan/(kW).To achieve the user-side grid connection, the power generation company only needs to reach 0.5~1.4 yuan/(kW ·H) OK.
In recent years, on a global scale, the price of pure polysilicon materials for manufacturing crystalline silicon cells has dropped from US$365.8/kg in October 2008 to US$36/kg in March 2012. Due to the oversupply situation will continue, polysilicon prices will continue to slow down. The decline in material prices directly reduced the price of solar cell modules from US$3.55/Wp in October 2008 to US$1.78/Wp in December 2009. In 2010, Chinese solar cell manufacturers priced between 1.55 and 1 US dollars/Wp. Since the beginning of 2013, the price has dropped to around US$0.7/Wp. This is the inevitable result of the rapid expansion of domestic and foreign application markets with the domestic solar cell and module production capacity reaching 30GW and the cost falling below 0.6 USD/Wp.