Principle of the solar cell Sunlight shines on the p-n junction of the semiconductor to form new hole-electron pairs. Under the action of the electric field of the p-n junction, holes flow from the n region to the p region, and electrons flow from the p region. to region n When a circuit is connected, a current is formed. This is how photovoltaic solar cells work.
1. Solar power generation methods There are two solar power generation methods, one is light-heat-electricity conversion method and the other is direct light-electricity conversion method.
(1) The light-heat-electricity conversion method uses thermal energy generated by solar radiation to produce electricity. Generally, a solar collector converts the absorbed thermal energy into steam as the working fluid and then drives it away. a steam turbine to produceelectricity. The first process is a light-heat conversion process; the second process is a heat-electricity conversion process, which is the same as ordinary thermal power generation. The disadvantages of solar thermal power generation are that its efficiency is very low and its cost is high. Its investment is estimated to be at least higher than that of ordinary thermal power generation. The power plant is 5-10 times more expensive. A 1,000 MW solar thermal power plant requires an investment of 2 to 2.5 billion US dollars. the average investment for 1 kW is 2,000-2,500 US dollars. Therefore, it can only be used on a small scale on special occasions, and large-scale use is not economically profitable and cannot compete with ordinary thermal or nuclear power plants.
(2) Method of direct conversion of light into electricityElectricity This method uses the photoelectric effect to directly convert solar radiation energy into electrical energy. The basic device for converting light into electricity is the solar cell. A solar cell is a device that directly converts solar energy into electrical energy through the photovoltaic effect. When the sun shines on the photodiode, the photodiode converts light energy from the sun into electrical energy, producing current. When many batteries are connected in series or parallel, a solar cell array with relatively large output power can be formed. Solar cells are a promising new energy source with three major advantages: solar cells have a long lifespan and can be invested once and used for a long time as long as the sun exists, they are different from production thermal energymic ; and nuclear energy production. In comparison, solar cells will not cause environmental pollution; Solar cells can be used in both large, medium and small sizes, ranging from a medium-sized power plant with a million kilowatts to a solar battery for a household. only, which is unmatched by other power sources.
Battery panel raw materials: glass, EVA, battery sheets, aluminum alloy shells, tin-plated copper sheets, brackets stainless steel, batteries, etc.
Can solar panels directly convert thermal energy into electricity?Solar panels are equipment components that absorb sunlight and convert solar radiation energy into electrical energy directly by photoelectric effect or indirectly by photochemical effect. This is an energy production productenergy-saving and environmentally friendly energy which has been rapidly developed and promoted in recent years and is widely used in the construction of large-scale photovoltaic power plants, household distributed solar power generation systems, solar power products mobile device charging and aerospace technology.
1. Solar panels mainly consist of the following parts
1. The types of cells used in solar panels can be distinguished. Mainly ordersAmong them, monocrystalline silicon and polycrystalline silicon cells have simple production equipment and technology, and the product conversion rate is high, but they consume a lot of silicon materials and losses, hence the cost of silicon. cells is also high. Amorphous silicon cells are also called thin film solar cells, including siliconamorphous m-germanium, copper-indium-gallium selenide, gallium arsenide, cadmium telluride, etc. Due to the complex production process, the equipment and technology costs are relatively high, but because they do not use silicon The cost of materials and cells is very low, and the efficiency of photoelectric conversion has reached the level of crystalline silicon. Even gallium arsenide is widely used in high-end fields such as aerospace satellites with more than 31%. low-light power generation performance and can generate electricity under light. Characteristics such as smoothness are also impossible to achieve with crystalline silicon cells.
2. The packaging material to protect the cells. Crystalline silicon cells cannot be bent and must use ultra-white tempered float glass with lu transmissionhigh leafminer of more than 90%. plastic and ultra white tempered float glass.
3. Transparent EVA material, used for bonding, fixing and protecting packaging materials and battery sheets. The quality of EVA materials directly affects the lifespan of solar panels, but it is not easy to distinguish between good and bad when purchasing, so it is relatively safe to buy solar panels of major brands.
4. Others include junction boxes, sealing silicone, protective laminates, etc.
2. Application areas of solar panels
1. Large, medium and small power generation systems such as solar photovoltaic power plants, power generation on exterior glass walls of commercial buildings, distributed solar power. generation for residential households.
2. New energy vehicles, drones, satellites and rec equipmentexterior mobile harge.
3. Bus stops, park pavilions, street lights, traffic lights, signal towers, etc.
4. Power supply system for disaster relief equipment, power supply system for offshore operation platform, etc.
3. The power generation principle of solar panels
When sunlight irradiates the surface of the solar cell, part of the photons are absorbed by silicon materials or materials such as copper selenide , indium and gallium; the energy of the photons is transferred to the silicon atoms, etc., causing the electrons to transition and become free electrons which gather on both sides of the P-N junction to form a potential difference. If this happens When a circuit is turned on, under the action of voltage, current flows through the circuit to produce a certain output powertie, which is the process of converting photons. energy into electrical energy.
Article source: Zhongyi Industrial Thin Film Solar Technology Expert
Solar panels can directly convert thermal energy into electrical energy .
Solar power generation methods There are two solar power generation methods: one is the light-heat-electricity conversion method and the other is the light-direct conversion method. electricity.
1. The light-heat-electricity conversion method uses thermal energy generated by solar radiation to produce electricity. Generally, a solar collector converts the absorbed thermal energy into steam as the working fluid, and then drives a working fluid. steam turbine to produce electricity. The first process is a process of converting light into heat; the second process is a conver processsion of heat into electricity.
2. The direct light-to-electricity conversion method uses the photoelectric effect to directly convert solar radiation energy into electrical energy. The basic device for converting light into electricity is solar energy.Battery.
Monocrystalline silicon solar panels:
The photoelectric conversion efficiency of monocrystalline silicon solar panels is about 15%, with the highest reaching 24%. This is the highest photoelectric conversion efficiency among all types. of solar panels. The most effective, but the production cost is so high that it cannot be widely and commonly used in large quantities.
Since monocrystalline silicon is usually encapsulated in tempered glass and waterproof resin, it is strong and durable, with a lifespan of typically up to 15 years and up to 25 years.
Reference for the above content: Baidu Encyclopedia - Solar Panels