The Opinions of the CPC Central Committee and the State Council on Completely, Accurately and Comprehensively Implementing the New Development Concept and Doing a Good Job of Carbon Peak and Carbon Neutralization pointed out that we should accelerate the construction of a clean, low-carbon, safe and efficient energy system, actively develop non fossil energy, implement renewable energy substitution actions, vigorously develop wind energy, solar energy, biomass energy, marine energy, geothermal energy, etc., and constantly increase the proportion of non fossil energy consumption. As a relatively mature industry in the new energy industry, the solar energy industry is constantly providing support for the realization of the "double carbon" goal. In 2021, the installed capacity of solar power generation will be about 310 million kilowatts, with a year-on-year growth of 20.9%. The proposal of the "double carbon" goal also provides a new strategic development opportunity for the development of clean energy industries such as solar energy.

What is solar energy? What are the main application scenarios?

Solar energy is one of the main renewable energy sources, which has the characteristics of wide source, clean and harmless, sustainable, etc. In a broad sense, solar energy refers to the radiation energy from the sun, which is generated by hydrogen helium fusion of hydrogen atoms in the sun and releases huge nuclear energy. Its main application fields are photovoltaic power generation and photothermal.

Photovoltaic power generation is a technology that uses the photovoltaic effect of semiconductor interface to directly convert light energy into electrical energy. In 2021, the newly added photovoltaic grid connected installed capacity will be 54.88GW, up 13.9% year on year. The cumulative installed capacity of photovoltaic grid connection has reached 308GW, and the new and cumulative installed capacity is global *.

Photothermal is a modern solar thermal technology that aggregates sunlight and uses its energy to generate hot water, steam and electricity. At present, photothermal technologies are widely used, including photothermal power generation and solar water heater utilization. Solar thermal utilization mainly focuses on civil heating, agricultural production, industrial manufacturing and other industrial and agricultural heating scenarios, and is also the main development field of solar thermal utilization in the future.

Characteristics of solar photovoltaic industry chain

From the perspective of the solar photovoltaic industry chain, the upstream industry is the production link of raw materials, mainly the mining, refining and production of silicon ore and high-purity silicon materials, such as metallurgical silicon purification, polycrystalline silicon purification, single crystal/polycrystalline silicon wafer processing and cutting. In addition, it also includes the manufacturing of system accessories such as solar power backplane and battery glass.

The midstream industry is the core link of technology, mainly the R&D and manufacturing of parts and components. It includes the production and assembly of single crystal/polycrystalline silicon cells and cell modules (crystalline silicon modules, thin film photovoltaic modules).

Downstream industries include the system integration and installation of photovoltaic products, including solar grid connected power generation project, production and installation of solar cell modules, photovoltaic integrated buildings, etc.

The future development of solar energy is promising

At present, the future development and application of solar energy technology should be promising in green hydrogen energy, liquid solar methanol and solar power generation.

Liquid sunlight methanol is used to realize the storage, transportation and utilization of solar energy in the form of methanol. It is divided into two steps: the clean energy such as solar energy decomposes water to produce "green hydrogen"; The reaction of green hydrogen and carbon dioxide to produce methanol or other fuels and chemicals is an important technological path to achieve the goal of "double carbon".

Solar power generation achieves the purpose of power generation by collecting solar heat energy, using heat exchanger to provide steam, and combining the process of traditional turbine generator. The use of solar thermal power generation technology can avoid the expensive silicon crystal photoelectric conversion process and greatly reduce the cost of solar power generation. Experts said that the new energy structure in the future will be the coordinated development of photovoltaic, wind power and solar thermal, and the form of multi energy complementation.