Solar energy power generating is a typical sort of environment-friendly energy source with numerous advantages such as safe and reliable, noise-free, pollution-free, non-restricted by location, not requiring fuel consumption, mechanical movement parts free, low in failure rate, convenient in maintenance, attendance free, free to choose the scale and size and convenient to be adopted to specific buildings, all of which are not provided by conventional power generations and other ways of power generation. Its application also proves to be an ideal solution to the energy source problem in the sustainable development of the mankind on the earth. Countries in the world such as Japan, Germany, Holland, Italy, Spain, Switzerland, Finland, Austria, the Great Britain and Canada have made their own photovoltaic development plans, through which a strong competitive power is expected in the field of environment-friendly new energy source research and application in the new meelenium.

   The world largest roof PV power system is installed in the new world trade center of Munich, Germany, with a capacity of 1MW, which has become one of the modern architectures of which German people feel proud of. Throughout the 1990s, the sales volume of solar cells in the world has been increasing by 25%-30% annually, and exceeded 200MWp in 1999. Faced with such a rapid increase rate, arising industry has taken shape, which people call PV industry. Countries including America, Japan and European community have all launched new ¡°roof programs ¡± and ¡°sunny programs¡± one after another. It is predicted that by the year of 2010, solar cells used in the above countries and regions for roof power system will exceed 12000MWp(approximately equivalent a conventional power plant of 12 million Kw.), which is of massive scale, whether in terms of environmental protection benefits or economic benefits.

   Development history of the research, manufacture and application of China¡¯s PV power technologies is approximately, synchronized with the development course of the world , with a history of over 30 years. At present, China possessed an annual production capacity of 6MWp for various solar cells, with products mostly distributed to be the five provinces in Northwest China and areas without electricity such as Tibet and Sichuan, and the largest independent power station is built in Tibet, with a capacity of 100KWp. In recent years, in developed regions of our country, usage of solar cells has increased rapidly, e.g. those as communication power source for express highways, power source for maritime navigation marking lights, power source for cathodic protection of petroleum pipelines and gas delivery pipelines power source for obstacle light, etc. Following the solar water heaters that have been extensively used in China, the roof PV power source system has become the focus of attention in the field of solar energy. In Shenzhen, China, the roof PV power plant with a capacity of 100KWp has been established to supply energy for industrial production. After entry into the 21st century, the solar architecture demonstration project of Beijing Asian Games Village has started construction, with a total investment of RMB 40 million, which turned a new page in China¡¯s large cities¡¯ utilization of solar energy.

   Being the largest developing country in the world, China has now an electroless population of about seventy million. There still exist eleven electroless countries all over the country with quite a member of electroless townships and villages in the border and remote districts which are located far away from the power supply net and which will find the photovoltaic power system one of the best solution to their thirst for electricity. Even in a highly modernized metropolitan city like Shanghai, the shortage in the energy source will become more and more grave. A good explanation is the grave shortage in the power available in the summers and winters in the recent years. Hence the energy source is an issue attracting great attention from cities as well as rural areas with regard to the sustainable economy development and ecological environment optimization.

   With our governments¡¯ further support to the photovoltaic industry, the application of the solar energy photovoltaic system at home can perceive further development and the modules can perceive flourishing demands from the photovoltaic power station communication power source, the cathodic protection, weather forecasting, forest fire protection, maritime navigation marking lights and the newly born users like solar energy telephones, cameras, air-conditioners, TV sets, refrigerators and other domestic applications. With an annual increase of 30%, the market is being built up at a tremendously high speed.