Solar panels are already used to power the most diverse technology: from mobile gadgets to electric vehicles. How are arranged, what are and what are capable of modern solar cells, you will learn from this article.
History of creation
So historically, solar panels – this is the second attempt of mankind to curb the infinite energy of the Sun and make it work for itself for good. The first appeared solar collectors (solar thermal power plants), in which electricity produces heated to boiling point water under concentrated solar rays.
Solar batteries directly produce electricity, which is much more efficient. With direct transformation, much less energy is lost than with multistage, like in collectors.
Principle of operation
A semiconductor is such a material, in the atoms of which either there are extra electrons (n-type), or vice versa, they are not enough (p-type). Accordingly, the semiconductor photocell consists of two layers with different conductivity. An n-layer is used as a cathode, and a p-layer is used as an anode.
The extra electrons from the n-layer can leave their atoms, while the p-layer captures these electrons. It is the rays of light that “knock out” electrons from the atoms of the n-layer, after which they fly into the p-layer to occupy empty spaces. In this way, the electrons run in a circle, leaving the player, passing through the load (in this case, the battery) and returning to the n-layer.
Mass production of solar cells became possible after the telecommunications company Bell Telephone developed a silicon-based photocell. He still remains the most common material in the production of solar cells. True, the purification of silicon is an extremely costly process, and therefore alternatives are being tried little by little: compounds of copper, indium, gallium, and cadmium.
It is clear that the power of individual solar cells is not enough to supply powerful electrical appliances. Therefore, they are combined into an electrical circuit, thereby forming a solar battery (another name is a solar panel).
The leaders in global solar cell production are Suntech, Yingli, Trina Solar, First Solar and Sharp Solar. The first three represent China, the fourth – the United States, and the fifth, as you might guess, is a division of the Japanese corporation Sharp.
The American company First Solar not only produces solar cells, but also takes a direct part in the design and construction of solar power plants. The most powerful in the world SES Agua Caliente, which is located in Arizona, USA – the work of First Solar engineers.
The largest Ukrainian SES, Perovo, was built and supplied with solar panels by the Austrian company Activ Solar.
The Chinese company Suntech has become famous for preparing for the 2008 Summer Olympics a football stadium called “Bird’s Nest” in Beijing. The electricity generated during the day with the help of solar batteries is accumulated and then used to illuminate the stadium, water the grass on the football field and work telecommunications equipment.
Two decades ago, microcalculators with photocells appeared to be a novelty, which made it possible not to change the “battery-tablet” in them for years. Now, mobile phones with a solar panel integrated in the back cover do not surprise anyone. But this is a trifle in comparison with cars and airplanes (albeit unmanned), which have learned to move using only solar energy.
The future of solar cells is seen exactly as bright as the sun itself. I want to believe that it is the solar batteries that will finally cure smartphones and tablets from “rosette dependence”.