The sun is a natural source of energy. The ability of every living creature on Earth to function, or even to survive, is due to the energy that comes directly or indirectly from the sun. As a new energy source, solar energy has three major advantages over conventional energy sources:
First, it is the most abundant source of energy available to mankind. It is estimated that in the past 1.1 billion long years, the sun consumed 2% of its own energy, which can be said to be inexhaustible.
Second, the earth, no matter where there is solar energy, can be developed and used locally, there is no transportation problems, especially for the rural areas, islands and remote areas of underdeveloped transportation is more valuable to use.
Third, solar energy is a clean energy, in the development and use, will not produce waste, waste water, waste gas, and no noise, and will not affect the ecological balance.
Our earth is almost 100 million miles away from the sun. The amount of radiation energy it intercepts is incredibly small (about three parts per million), and such a small amount of energy is actually 100,000 times larger than the current power generation capacity of the entire world. The world, and especially the industrially developed countries, are now beginning to feel the shortage of energy, so people are turning to solar energy to solve the energy crisis.
Solar energy is a form of radiant energy that we cannot use directly, so we have to convert the sunlight before we can use it.
At present, the most widely used is the conversion of solar energy into electricity. The process of converting light energy directly into electricity is called the photovoltaic effect to be exact. The energy in the light is captured by the electrons of the semiconductor device without any other mechanical parts, and electricity is generated. This conversion of light energy into electrical energy energy converter, is the solar cell. Solar cells are also composed of semiconductors, just like electric crystals. Its main material is silicon, but there are also some other alloys. The high purity silicon used in the manufacture of solar cells is made through a special purification process. Solar cells as long as the sunlight or light irradiation, will be able to convert light energy into electricity, so that the current flow from one side to the other, generally can be issued equivalent to 10% to 20% of the light energy received electricity.
Shandong Shantai Group will be LED street lights and solar cells combined, is a good example of the application. During the day, the solar panel absorbs sunlight to reserve electricity, and at night or when it is dark outside, it automatically senses the external environment and starts lighting. This not only eliminates the need for traditional street light installation cables and wires, but also uses natural energy without the need to generate power. In today's sustainable development and low carbon environmental protection, its significance is extremely far-reaching.
At present, the application of solar cells has been from the military field, the aerospace field into the industrial, commercial, agricultural and other industries and communications, household appliances and utilities, especially in remote areas, mountains, deserts, islands and rural areas, in order to save the high cost of transmission lines. However, at this stage, its cost is still very high, sending a kilowatt of electricity requires an investment of tens of thousands of dollars, so large-scale use is still limited by the economy.
In the long run, with the improvement of solar cell manufacturing technology and the invention of new photoelectric conversion devices, the protection of the environment and the huge demand for renewable clean energy, solar cells will remain a more practical and feasible way to use solar radiation energy, which can open up broad prospects for the future large-scale use of solar energy for human beings.
