How Solar PV Really Works
Did you know that the amount of solar energy that the Sun pours on Earth every day is 10,000 times greater than that consumed by the entire planet that same day? Solar energy is an inexhaustible source of energy that can be used both to produce electricity as thermal energy through various devices and photovoltaic cells.
What is a solar panel and how does it work?
How Solar PV Really Works
Photovoltaic solar energy is the one that takes advantage of the sun’s radiation to carry out the process of generating electricity. It is a clean and renewable energy, but what exactly is solar energy? And photovoltaic solar energy? We explain it in more detail below.
What is solar energy?
Solar energy is the energy that is produced directly from the sun through the radiation emitted by this star. This energy has a favorable effect on the planet, conserving temperature and helping to conserve biodiversity. It is one of the main reasons why there is life on the planet.
This energy is an inexhaustible resourceIn fact, it is estimated that since the birth of the Sun, 10,000 million years ago, 50% of its total energy has not yet been consumed. As you can see, it is an inexhaustible energy with no expiration date.
Now, how is solar energy harnessed? What is photovoltaic solar energy? Solar energy can be harnessed in two ways. On the one hand, to generate thermal energywhich is achieved through collector solar panels —or collectors— and, on the other hand, to generate electrical energywhich is achieved through photovoltaic solar panels, or photovoltaic systems.
This last case, which is the one that concerns us in this article, we now see in more detail.
How is photovoltaic solar energy generated?
As we explained, photovoltaic solar energy is generated by photovoltaic solar panels through a complex procedure that is finally translated into electricity. The photovoltaic system consists of a set of cells or photovoltaic cells that produce electricity thanks to the sunlight that falls on them. This is known as photoelectric effect.
To explain the generation of photovoltaic energy and the process that is carried out, it must be taken into account that the cells or cells mentioned are made with a special material that allows the use of solar radiation. photovoltaic cells can be crystalline or amorphous. In the case of the crystalline ones, in turn, they can be monocrystalline or polycrystalline —all of them with silicon as the main component—. The operation of the photovoltaic system is governed by several factors. It must be taken into account that each cell of the photovoltaic panel has two layers of semiconductor material, this is the silicon -as we explained- In order for each cell to work, it is necessary to generate an electric field. This occurs when opposite charges separate. Therefore, to achieve this electric field, what is done is to mix the silicon with other materials, giving each layer of the cell a positive and a negative charge.
Specifically, what is mixed is phosphorus in the upper layer of silicon —which adds electrons with a negative charge— and boron, in the lower layer —which generates the positive charge—. Thanks to this system what occurs is a flow of electricity. This is so because the photons of solar radiation fall on the first layer of the panel cells, being absorbed by the semiconductors. When this photon hits the free electron, the electric field causes it to be pushed out of the silicon to which it had been attached. Next, the metallic conductive plates that are located on the sides of each photovoltaic cell collect these electrons and transfer them through cables. This explains the generation of photovoltaic energy and the process it carries out.
Photovoltaic solar energy applications
The application of photovoltaic solar energy is very varied, especially due to the different uses of electricity. However, if we refer to the way in which this energy is used, we can make a clear distinction between two methods:
to) Self-consumption: On the one hand, we have the use of photovoltaic solar energy as a self-consumption method. In this case, what is done, and it is increasing, is to use photovoltaic systems to generate electricity for the self-consumption of an individual. For this, a solar energy kit is installed that will provide electricity through photovoltaic solar panels. This solar energy kit can be very varied. In fact, we can find several types, depending on the way in which electricity is used. These are the solar energy kit with discharge of electricity to the general electrical network and the solar energy kit without discharge to the general electrical network. Each one with similar characteristics, but for different conditions. Public lighting in some cities also uses this type of photovoltaic installations —with batteries— to illuminate the residential areas of the city.
b) Large photovoltaic plants: Initially, these were the pioneers in using this type of photovoltaic systems to supply electricity. A clear example of this are the large industrial complexes, as well as solar pumping photovoltaic installations, used to save costs for this supply and obtain it autonomously.
Is photovoltaic solar energy beneficial?
Of course it does, photovoltaic solar energy stands out for being an inexhaustible source of energy, as we mentioned in the introduction, but also for being a renewable source of energy —since it takes advantage of the inexhaustible resources of nature, such as solar radiation in this case, to produce —. In addition, we must not forget that photovoltaic solar energy is a non-polluting resource. The use of photovoltaic systems does not pollute the environment and does not harm people’s health. They are devices that provide electricity without polluting and without generating waste. That is why global trends point towards the use of these solar panels and the reason why they have acquired such a good reputation.