The future of solar cells: the advantages of thin films will be great in the future
In the "Twelfth Five-Year" energy plan, the government proposed to optimize the energy structure, requiring non-fossil energy consumption to increase to 11.4% and non-fossil energy generation capacity to 30%. LED street lamp manufacturers are a kind of solid-state cold light source, which has the characteristics of environmental protection, no pollution, low power consumption, high luminous efficiency, and long life. Therefore, LED street lamps will become the choice for energy-saving road lighting. LED street light is a kind of high-efficiency solid-state light source formed by semiconductor PN junction that can emit light with weak electric energy. Under a certain forward bias voltage and injection current, the holes injected into the P zone and the electrons injected into the N zone are in After being diffused to the active area, photons are emitted through radiation recombination, which directly converts electrical energy into light energy. In the process of formulating the "13th Five-Year Plan", solar energy, as an emerging strategic resource, is an important part of future energy and will continue to be a key support project. LED street light is a kind of high-efficiency solid-state light source formed by semiconductor PN junction that can emit light with weak electric energy. Under a certain forward bias voltage and injection current, the holes injected into the P zone and the electrons injected into the N zone are in After being diffused to the active area, photons are emitted through radiation recombination, which directly converts electrical energy into light energy. The state has issued a series of plans and incentive policies to promote the healthy development of the solar photovoltaic power generation industry. Today's industrialized solar photovoltaic products are mainly two types of solar cells: silicon wafer-based crystalline silicon solar cells, such as monocrystalline silicon solar cells and polycrystalline silicon solar cells; and thin film solar cells.
In view of the advantages of thin-film solar cell modules in BIPV, compared with crystalline silicon solar cell modules, thin-film solar cell modules have the advantages of large power generation, low light intensity, and good high-temperature performance. In the morning, the power generation performance of thin film modules under low light/low temperature conditions is slightly higher than that of crystalline silicon; at noon, the high temperature effect of thin film modules is obvious, and the power generation performance of thin film modules is significantly better than that of crystalline silicon. At night, the power generation performance of thin-film modules is better than that of crystalline silicon modules under low light/high temperature conditions. In the case of the same rated power, the daily output of thin-film modules is higher than that of silicon modules. At the same time, thin film components have excellent low-light and high-temperature performance. Taking a silicon-based thin-film ground-based demonstration power plant as an example, during the high-temperature season from May 2014 to September 2015, according to continuous monitoring of the power generation of thin-film silicon and crystalline silicon, it was found that the MOR generated by thin-film modules was 25%. The power during this period is greater than that of crystalline silicon.
In addition to the above advantages, thin-film solar cell modules also have the advantages of beautiful appearance, good integrity, flexibility, and light weight.
In recent years, the solar photovoltaic cell market is shifting to thin-film solar photovoltaic products. The advantages of thin-film solar cells are: thin-film solar cells have low energy consumption, wide selection of preparation materials, diverse preparation processes, higher power generation per watt than crystalline silicon solar cells, high power generation efficiency, light weight, flexible products, and a wide range of applications. It is more suitable for the integration of photovoltaic buildings. Among them, the copper indium gallium selenium thin-film solar cell with a laboratory efficiency of more than 20% is a thin-film solar cell with high photovoltaic conversion efficiency. Because copper indium gallium selenium solar cells have no light decay effect, stable performance, high power generation efficiency, and environmental friendliness, they are the research hotspots of a new generation of high-efficiency thin-film solar cells in Europe and the United States.
The copper indium gallium selenium thin-film solar cell prepared by vacuum deposition technology not only records a conversion efficiency of 20.4%, but is also mature and large-scale industrialized, and the product is cost-competitive. The non-vacuum technology used to manufacture copper indium gallium selenide thin film solar cells has the potential advantages of low cost and easy large area, and has attracted more and more attention. Major copper indium gallium selenide thin film solar cell companies in Europe, the United States and Japan have module products with efficiencies exceeding 13%.
