1. Development history of photovoltaic power generation technology
The research history of photovoltaic power generation technology has more than 100 years.
In 1839, the French physicist Becquerel discovered the photovoltaic effect.
In 1883, Charles Fries trial-produced a “sunlight cell” as a sensor device, but the efficiency was only 1%.
In 1930, Lange first proposed the idea of using photovoltaic effect to make “solar cells”, which was the earliest proposal for solar power generation.
In 1931, Bruno immersed a copper compound and selenium-silver electrodes in the electrolyte and started an electric motor in the sun.
In 1941, Orr discovered the photovoltaic effect on silicon materials, and the research on solar cells entered the stage of practical application.
In the 1950s, there was a major breakthrough in solar cell technology.
The world’s first practical solar cell was born in 1954. Scientists Chapin and Pilsson at Bell Labs in the United States have successfully developed a monocrystalline silicon solar cell with an efficiency of 6%. This can be seen as the beginning of the industrialization of photovoltaic cells. In the same year, Weckel discovered that gallium arsenide has a photovoltaic effect and made the first thin-film solar cell on glass.
In 1955, the first photoelectric navigation light came out.
In 1958, the conversion efficiency of monocrystalline silicon cells had reached 14%. The second man-made satellite “Pioneer 1” launched by the United States on March 17 of the same year used monocrystalline silicon solar cells as the power source for the radio transmitter. This is the first application of solar cells in space.
In 1959, the first polysilicon solar cell came out with an efficiency of 5%.
In 1960, silicon solar cells realized grid-connected operation for the first time.
In 1974, Japan began to implement the Sunshine Plan and implemented government subsidies for photovoltaic power generation systems.
In 1975, amorphous silicon solar cells came out.
In 1978, the United States built a 100kWp ground photovoltaic power station. In 1983, a 1MWp photovoltaic power station was built. In 1986, another 6.5MWp photovoltaic power station was built.
In 1996, the United Nations held the “World Solar Energy Summit” in Zimbabwe, published the “Harare Solar Energy and Sustainable Development Declaration”, discussed the “World Solar Energy 10-year Action Plan (1996-2005)”, “International Solar Energy Convention”, “World “Solar Energy Strategic Plan” and other important documents.
In 2000, the technology of combining solar cells and buildings formally began to develop.
Tips: Wp is the specification unit of photovoltaic cells or photovoltaic power generation systems. It means the output power of photovoltaic cells (Watt) when the air quality is AM 1.5 and the solar radiation intensity is 1kW/m² and the battery temperature is 25°C. It is called peak watts. (Peak Watt). In most cases, the output power of photovoltaic cells does not reach its nominal Wp
2. Development status of photovoltaic power generation industry
Since the first practical monocrystalline silicon photovoltaic cells appeared in the 1950s, photovoltaic cells entered space applications in the late 1950s, and ground applications in the late 1960s, solar photovoltaic power generation technology has gone through more than half a century.
In 2004, photovoltaic cells began to flourish in the global energy market and began to form an industry.
At present, the power levels of photovoltaic cells are very rich, ranging from solar photovoltaic power plants of 100kW to 10MW, as small as power supplies for watches and calculators. The conversion efficiency of the best monocrystalline silicon solar cells in the laboratory has reached 24%. The conversion efficiency of polycrystalline silicon solar cells reaches 15%, the conversion efficiency of arsenic inlay solar cells reaches 27%, and the conversion efficiency of specially made gallium arsenide solar cells in the laboratory has even reached 35%~36%.
The changing trend of world solar cell production in recent years is shown in Figure 2. In 2012, the world’s annual output of solar cell modules reached 38.5Gw.
In 2007, the output of solar cells in China was about 1100Mw, while the output of Europe, Japan and the United States were 1062MW, 920MW and 266Mw respectively. China has become the veritable solar cell output in the world.From 1995 to 2013, the main producer of photovoltaic cells was the largest in the world. The market share is shown in Figure 3.
For every doubling of the output of photovoltaic cells in the past 20 years, the price of photovoltaic cells has dropped by 20%. According to the estimation of the US Department of Energy, the cost of photovoltaic power generation in 2003 was about 30 US dollars per kilowatt hour. It will take more than 20 years to bring the price of photovoltaic power generation down to 2 cents per kilowatt hour. If some effective new technologies are adopted, this time is expected to be shortened to 10-15 years.
The low-power application of photovoltaic power generation has become more common, and now it is developing towards high-power applications.
The installed capacity of solar photovoltaic power generation increases year by year with the increase in production, as shown in Figure 4. Germany is the country with the largest cumulative installed capacity of photovoltaic power generation in the world, accounting for 26% of the world’s cumulative installed capacity of photovoltaic power generation in 2013, and both Italy and China are 13%.