What is the related technical explanation of solar energy applications, I believe that many people have a probably understanding of the solar energy, and the photovoltaic power generation in solar application technology, main two aspects: principle and its Advantage . 1. Solar photovoltaic power generation principle
The photovoltaic effect occurs in the liquid and solid matter, but only the photoelectric conversion of the solid (especially the semiconductor PN junction) under solar light. Higher efficiency. The crystal silicon solar cell is made by using the photovoltaic effect principle, and the light energy of the sun can be directly converted into electrical energy. The energy converter of solar photovoltaic power generation is a solar cell, also known as the photovoltaic battery, and is the basis and core device of the solar photovoltaic power generation system. Solar energy conversion has become an electrical energy, including 3 steps:
1. After absorbing a certain energy of the photon, the semiconductor produces an electronic hole pair, called \”light carrier\”, and the electrode of both In contrast, the electronic belt is negative, and the hole is positively charged.
2. The opposite side of the electrode is separated by the electrostatic field generated by the semiconductor PN junction.
3. Light carrier electrons and holes are collected by the positive and negative electrodes of the solar cell, and current is generated in the outer circuit, thereby obtaining electrical energy.
The principle of solar photovoltaic power generation is shown in the following figure. When the light illuminates the solar cell surface, a portion of the photons are absorbed by the silicon material, and the energy of the photon is transmitted to the silicon atom, making the electron transition, becomes free electrons, and forms a potential difference between the PN junction. When the external circuit is turned on, under the action of the voltage, there will be a current flow through an external circuit to generate a certain output power. The essence of this process is the process of converting photon energy into electrical energy.
In the solar power system, the total efficiency η of the system is determined by the photoelectric conversion efficiency of the solar cell module, the controller efficiency, the battery efficiency, the efficiency of the inverter efficiency, and the load. At present, the photoelectric conversion efficiency of solar cells is only about 17%. Therefore, improve the photoelectric conversion efficiency of the solar cell module, reduce the unit power cost of the solar photovoltaic power generation system, and is the key and difficulty of solar photovoltaic power generation industrialization. Since the advent of solar cells, crystalline silicon is maintained as a main material. At present, research on silicon solar cell conversion efficiency is mainly surrounding the suction surface (such as using double-sided battery to reduce reflection), improve the conversion efficiency of silicon A Type Ground Solar Mounting System, and battery ultra-thinness, etc. aspect.
The solar photovoltaic power generation system is mainly used in the following three large aspects
to provide power supplies in powerless applications, mainly provide electricity for the living production of residents in powerless regions, for microwave relay stations and The mobile phone base station provides a power supply or the like.
2, solar daily electronic products, such as all kinds of solar chargers, solar energyStreet lights and solar lawn lamps, etc.
3, grid power generation, access to the national grid. my country’s photovoltaic grid power generation has been very mature. Since 2013, the state has introduced a series of photovoltaic power promotion policies, encourages regional industrial and commercial and household, public buildings, etc. 2, the advantages of solar power
By comparing biomaria, water energy, wind energy, and solar energy, the comparative analysis of common new energy, can be clearly seen Solar power generation has the following unique advantages.
Photovoltaic power generation has an economic advantage
Of the economics of solar utilization can be seen from two aspects: First, the solar energy is not exhausted, inexhaustible, Moreover, no \”tax\” does not receive any \”tax\” when receiving solar energy, and can be taken with the current level of technology, and some solar energy use has economically. With the development of technology and the breakthrough of human development and utilization of solar technology, the economics of solar utilization will be more obvious. If the 20th century is the century of oil, then the 21st century is a century (solar century) of renewable energy (centuries).
From the construction cost of solar photovoltaic power station, with the large-scale application and promotion of solar photovoltaic power generation, especially the upstream crystal silicon industry and photovoltaic power generation technology, building roof, exterior wall and other platforms Compound development, the construction cost of each kW solar photovoltaic power generation is getting lower and lower, compared to other renewable energy has the same economic advantage, and the popularity will become wider and wider as the country’s parity is implemented.
2, solar energy is an endless renewable energy
According to the calculation, the total amount of solar energy to reach the surface of the earth within one year is about 1.892×10 ^ 24 tons, is currently 10,000 times the main source of the world’s main energy source. At least 4 billion years old, the time that the solar energy source can be said to be unlimited, which determines that the development and utilization of solar energy will be the lack of conventional energy, the most effective way.
3, the environment is not polluting
Solar energy like wind energy, tidal energy, etc. Sex, is an ideal alternative energy source. Due to the traditional fossil fuel (coal, oil and gas) discharge a large amount of toxic and harmful substances during use, it will cause serious pollution to water, soil and atmosphere, forming greenhouse effects and rains, seriously endangering human living environment and health, so Urgently need to develop new comparison, alternative energy sources, and solar energy as a more ideal clean energy, is being received by countries around the world.
From the current carbon emission rate of various power generation modes (G/ kW · h), do not calculate the upstream link: coal power generation is 275g / kW · h, oil power generation is 204g / kW · h, natural gas power is 181g / kW · h, wind power is 20g / kW · h, Solar photovoltaic power generation is close to zero emissions. Further, there is no waste, waste, wastewater, exhaust gas discharge during power generation, no noise, does not produce harmful substances to the human body, will not pollute the environment.
4 In the middle, solar photovoltaic power generation has the least conversion link, which is most direct. In general, in the energy flow of the entire ecological environment, with the increase in the conversion link, the loss of the conversion chain will increase geometric level, and greatly increase the construction, operating cost and instability of the entire system. . At present, the photoelectric conversion efficiency of crystal silicon solar cells is 15% -20%, and the highest level of laboratory has reached 35%.
5, the most economical, most environmentally friendly
From the perspective of resource conditions, especially land occupancy, biological energy, wind energy is more demanding, and solar utilization is flexible . If the solar photovoltaic power generated land area is 1, the wind is 8-10 times the solar energy, and the biological energy is 100 times. In terms of hydropower, the completion of a large dam often needs to overunde hundreds of square kilometers to the land of hundreds of square kilometers. In contrast, solar power does not need to take more land, roof, and the wall can become a place for solar photovoltaic power generation. It can also take advantage of our vast desert in my country. By building solar photovoltaic power generation bases in the desert, directly reduce the desert The solar radiation fluid into the surface is effectively reduced to reduce the surface temperature, reducing evaporation, so that the survival and growth of plants can be considerably, stabilize and reduce sand dunes, and have requested the desired clean renewable energy to nature. . Solar energy has universality of most parts of the earth, which can be taken in place. This provides a better future for countries and regions lacking routine energy.