What's PV ?
What's PV ?
PV (Photovoltaic) power generation is a technology that uses the photovoltaic effect of the semiconductor interface to directly convert light energy into electrical energy. It is mainly composed of solar panels (components), controllers and inverters. The main components are composed of electronic components. After the solar cells are connected in series, they can be packaged and protected to form a large-area solar cell module, and then combined with power controllers and other components to form a photovoltaic power generation device.
principle
The main principle of photovoltaic power generation is the photoelectric effect of semiconductors. When a photon shines on a metal, its energy can be absorbed by an electron in the metal. The energy absorbed by the electron is large enough to overcome the internal gravity of the metal to do work, escape from the metal surface and become a photoelectron. Silicon atoms have 4 outer electrons. If pure silicon is doped with 5 outer electrons such as phosphorus atoms, it becomes an N-type semiconductor; if pure silicon is doped with 3 outer electrons, such as Boron atoms form a P-type semiconductor. When the P-type and N-type are combined, the contact surface will form a potential difference and become a solar cell. When sunlight hits the P-N junction, current flows from the P-type side to the N-type side, forming a current.
The photoelectric effect is a phenomenon in which light causes a potential difference between different parts of a non-uniform semiconductor or a combination of semiconductor and metal. It is the process of converting photons (light waves) into electrons and light energy into electrical energy first; secondly, it is the process of forming voltage.
After ingot casting, ingot breaking, slicing and other procedures, polysilicon is made into silicon wafers to be processed. Doping and diffusing a small amount of boron, phosphorus, etc. on the silicon wafer forms a P-N junction. Then screen printing is used to print the finely prepared silver paste on the silicon wafer to make grid lines. After sintering, the back electrode is made at the same time, and a layer of anti-reflection coating is applied to the surface with grid lines. So far made. The battery slices are arranged and combined into a battery assembly to form a large circuit board. Generally, an aluminum frame is wrapped around the module, the front is covered with glass, and the electrode is installed on the back. With battery components and other auxiliary equipment, a power generation system can be formed. In order to convert direct current to alternating current, a current converter needs to be installed. After power generation, it can be stored in batteries, or it can be fed into the public grid. In the cost of the power generation system, battery components account for about 50%, and current converters, installation fees, other auxiliary components and other costs account for the other 50%.
Features
Folding advantages
Regardless of the world or China, conventional energy is very limited. China's primary energy reserves are far below the world's average level, only about 10% of the world's total reserves. Solar energy is an inexhaustible and inexhaustible renewable energy source for human beings. It has sufficient cleanliness, absolute safety, relative universality, a certain long life and maintenance-free, sufficient resources and potential economy. Such advantages have an important position in the long-term energy strategy.
Compared with commonly used thermal power generation systems, the advantages of photovoltaic power generation are mainly reflected in:
① No risk of exhaustion;
②Safe and reliable, no noise, no pollution discharge, absolutely clean (no pollution);
③The advantages of building roofs can be used without being restricted by the geographical distribution of resources; for example, areas without electricity and areas with complex terrain;
④On-site power generation and power supply can be achieved without consuming fuel and erecting transmission lines;
⑤High energy quality;
⑥Users are easy to accept emotionally;
⑦The construction period is short, and the time it takes to obtain energy is short.
