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What is photovoltaic?

Photovoltaic: short for solar power generation system, it is a new type of power generation system that directly converts solar radiation energy into electric energy by using photovoltaic effect of semiconductor materials of solar cells. There are two modes of independent operation and grid-connected operation.

Photovoltaic power generation is a technology that directly converts light energy into electric energy by using photovoltaic effect of semiconductor interface. The key part of this technology is solar cells. After the solar cells are connected in series, they can be packaged and protected to form a large-area solar cell module, and then form a photovoltaic power generation device with power controllers and other components.

The main concrete principle of photovoltaic power generation is the photoelectric effect of semiconductors. When a photon irradiates a metal, its energy can be completely absorbed by an electron in the metal. The energy absorbed by electrons is large enough to overcome the gravity inside the metal and escape from the metal surface to become photoelectrons. Silicon atoms have four outer electrons. If pure silicon is doped with atoms with five outer electrons, such as phosphorus atoms, it becomes an N-type semiconductor. If pure silicon is doped with atoms with three outer electrons, such as boron atoms, a P-type semiconductor is formed. When P-type and N-type are combined, the contact surface will form a potential difference, which will become a solar cell. When sunlight strikes the P-N junction, holes move from the P-pole region to the N-pole region, and electrons move from the N-pole region to the P-pole region, forming a current.

The photoelectric effect mentioned above is the phenomenon that light causes potential difference between uneven semiconductor or different parts of semiconductor and metal. First of all, it is a process from photons (light waves) to electrons, and from light energy to electric energy. Secondly, it is the process of forming voltage.

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