Application of Silicone Materials in Solar Power Generation


Whether used independently or connected to the grid, photovoltaic power generation system is mainly composed of solar panels (components), controllers and inverters, which are mainly composed of electronic components. The layout of photovoltaic power generation is flexible. It can build large-scale photovoltaic power plants, install photovoltaic cells on roofs, and even on mobile devices. With the development of smart grid in the future, home photovoltaic power generation can be merged into the grid at will, and the development prospects are far-reaching.


At present, there are three kinds of widely used solar cells: monocrystalline silicon, polycrystalline silicon and amorphous silicon. In recent years, compounds other than indium phosphide, gallium arsenide, indium, selenium and copper have also appeared.


2.2 Solar Photothermal Power Generation Technology


Solar photothermal power generation technology is the use of optical systems to collect solar radiation energy, with its heating medium to generate steam, to drive turbogenerators to generate electricity. According to the different concentrating modes, solar photothermal power generation can be divided into four types: tower, trough, disc and Fresnel focusing. At present, trough solar power generation system and tower solar power generation system have been commercialized. Disk solar power generation system has passed the demonstration stage, completed the technical verification, and is entering the commercial stage. Fresnel focused photothermal power generation research has achieved preliminary results.


The trough solar photothermal power generation system adopts the principle of "line focusing". Through a large area trough parabolic reflector, the sunlight is focused on a collector tube, the heat carrier in the tube is heated, and then high pressure steam is generated by heat conversion equipment, which is fed into a conventional steam turbine for power generation. The system is generally composed of a concentrating heat collector, a heat storage device, a heat engine generating device or/or an auxiliary energy device (such as a boiler). The concentrating system is the core of the system, which consists of a concentrating mirror, a receiver and a tracking device.


The basic form of tower photothermal power generation system is to collect sunlight onto a receiver fixed on the top of the tower by using a group of heliostat which can track the sun independently. The high temperature heat transfer medium is generated to heat steam to drive conventional turbogenerator units to generate electricity. This kind of power generation method does not need conventional energy, and the power supply comes from the high temperature heat transfer medium produced by solar radiation in the collector system. This photothermal power generation system mainly consists of heliostat array, tower, heater, heat transfer fluid, heat transfer components, heat storage system, control system, steam turbine and power generation system.


With the help of two-axis tracking and rotating parabolic reflector, the disc-type photothermal system gathers the incident solar radiation point by point, absorbs this part of radiation energy and converts it into heat energy by the heat absorber. The working medium is heated to drive the heat engine (e.g. gas turbine, Stirling engine or other types of permeability), thus converting heat energy into electric energy. This is the case. Disc photothermal power generation system is mainly composed of solar concave focusing mirror, receiver and generator. Solar Stirling power generation technology is to focus the Stirling generator directly.


Fresnel system is a simplified trough system. In fact, Fresnel system uses a set of flat mirrors to replace the parabolic surface mirror focusing in slot system. By adjusting and controlling the tilt angle of the plane mirror, the sunlight is reflected into the collector tube to realize focused heating. In order to simplify the system, water, oil or molten salt are usually used as heat absorbing medium. Compared with parabolic curved mirror, planar mirror is less difficult to fabricate, which greatly reduces the initial investment cost.


Whatever the technical route, because photothermal power generation uses conventional steam turbines, the current is stable, coupled with the system can introduce molten salt heat storage, salt will be changed from solid to liquid during the day, and water will be changed into steam power at night with molten salt of about 400 degrees Celsius. Thus, wind power and photovoltaic power generation can be solved most exciting. Headache peaking problem. As long as the scale is large enough, the cost of photothermal power generation is the most competitive among new energy sources.


Originality: Jiang Chengyong