Solar cells are devices that turn sunlight directly into electricity, which is regarded as clean energy.
Solar cells' applications
Solar cells are a type of technology that uses the photoelectric effect to transform light energy directly into electrical energy. Also known as (photovoltaic cell). As they don't require fuel or chemical processes to generate electricity, solar cells are a fundamental source of energy. They have no moving components, unlike electric generators. They lack the moving components seen in electric generators.
Small arrangements known as solar cell panels, which are used in homes to supplant the conventional energy supply, can be made of solar cells. In many rural areas where it is challenging to supply conventional energy sources, these panels are also employed. Solar cells are used to provide energy for most vehicles and space devices like space stations and satellites because they are fixed and do not require continuous main power.
Large groups of solar cells, known as arrays, may be made up of thousands of individual cells and are used to convert sunlight into electrical energy for distribution to industrial, residential, and commercial areas through central electrical stations. Also, they are employed in the production of portable radios, laptop computers, video games, and other gadgets.
Install solar cells
Silicon, indium phosphide, and indium copper selenide are examples of semiconductors that are used in solar cells to convert solar light energy into electrical energy. They primarily feature an anti-reflective layer to cut down on light loss. The anti-reflective layer is often comprised of silicon oxide, tantalum, or titanium, and is created using vacuum deposition or spin coating technique on the cell surface.
Moreover, there are three primary layers beneath the anti-reflective layer: the top conductive layer, the absorbent layer, and the rear layer. Moreover, the cell has positive and negative electrical layers.
The monocrystalline silicon slice from the electrical contact layer (positive), which is on the cell's face and contains some boron-like trivalent element impurities as well, both layers work together to transport electrical current to and from the solar cell, with the rear electrical contact layer (negative) consisting of pure silicon with the addition of phosphorus impurities.
The process through which solar cells work
The anti-reflection layer efficiently traps the incident light by improving its transmission to the next layers when sunlight strikes the solar cell. In contrast, the positive gaps move to the area where the positive chip connects, creating a voltage difference between the two surfaces of the bilateral link.
The two surfaces can then be connected by an electrical connector to create an electric current in an electrical circuit, where electrons move from the negative link to the positive link. We transform light energy into electrical energy in this way. It is important to note that when the cell's external circuit is opened, the cell generates a 0.07-ampere current and a 0.6-volt potential differential.
So providing an electrical power of 0.04 watts (according to the equation: electric power current x voltage difference), so if we want to run a pump with a capacity of 187 Watts, we will need an array of hundreds of solar cells linked in series and parallel, While the cells arranged in parallel indicate the intensity of the electric current and the cells linked in series define the quantity of the created voltage difference.
It must also be considered that the array's surface area produces a current of 4 amps per square meter. Moreover, it has a 48-watt electrical capacity. Moreover, four arrays, each one square meter in size, each containing 5000 solar cells linked in series and parallel, are required to power the pump.
How solar cells have changed?
The scientist (Beckerel) observed the photoelectric effect on various minerals and solutions while studying the features of the electric current generated by them in 1839. When the first time the photoelectric carrier concept was shown by two scientists (Adam and Smith) in 1877, the construction of the first selenium-based solar cell in 1883 allowed Fritz to introduce the idea to the public.
Scientists were able to describe the phenomena connected to photoelectricity thanks to the development of quantum mechanical theories, which also helped to explain the phenomenon of photosensitivity to materials like silicon, copper oxide, lead sulfur, and thallium sulfur.
The first silicon solar cell had a working efficiency of less than 1% in 1941, while the solar battery had a working efficiency of 6% by the mid-1950s. Solar cells were also developed using thin films consisting of cadmium sulfide and copper sulfide.
As the quantity of energy produced by the cells expanded from milliwatts to kilowatts, the solar cell industry underwent development due to the expansion of development research in the physical sciences and the study of electro-optical exchanges.
After the invention of solar cells in the 1970s and 1980s; As a result of advancements in the science of semiconductor installation at the microscopic level. During that time, solar cells (photovoltaic) emerged as one of the most significant and ambitious scientific technologies for producing electrical energy from solar energy.
As energy consumption increased, solar cell complexes (arrays) were built, which significantly reduced the price of energy consumption and allowed for production to reach tens of megawatts.
