Photovoltaic is an adjective to identify everything that has to do with photovoltaic energy and the photovoltaic effect, more specifically. This concept of solar energy refers to the generation of electricity through sunlight.
A photon is the particle that carries all forms of electromagnetic radiation, including visible light. On the other hand, a volt is the unit of electric current. In this way, it is easy to deduce the relationship between visible light or solar radiation with the generation of electrical energy or electricity.
We refer to the photovoltaic effect in everything related to obtaining energy through the action of light. The most used light source for photovoltaic installations is that coming from the Sun, that is, solar energy.
What Is the Photovoltaic Energy?
Photovoltaic solar energy is a method of obtaining electrical energy thanks to solar panels.
It is a renewable energy. All the amount of energy generated comes from the Sun. For this reason it is considered inexhaustible. Unlike fossil fuels, producing electricity does not emit greenhouse gases.
A solar panel is a set of photovoltaic cells or solar cells. Photoelectric cells are responsible for harnessing the sun's rays. They are devices that when receiving the photons are excited, cause electrons to jump. These electrons generate a small potential difference.
This property is called photovoltaic effect.
Classification and Types of Photovoltaic Energy
Photovoltaic systems are divided into 2 large families:
Isolated systems: they are not connected to any electrical distribution network.
Plants connected to the electrical network.
A particular case of an isolated system is the so-called "hybrid". Hybrid solar systems remain connected to the distribution network, but mainly use their resources. They can also work with other systems. For example: solar thermal, wind, even with an electric generator.
It can happen that none of the sources is available or the accumulator is downloaded. in this case, the system is connected to the electrical network.
Autonomous Photovoltaic Systems
It is used in installations isolated from other energy sources. That is, places where the electrical network does not reach for any reason. In these chaos, photovoltaic energy is a good solution.
The main components of an isolated photovoltaic system are:
Photovoltaic field, designated to collect energy through photovoltaic modules.
Management automation: it is a unit that can automatically switch between different renewable sources.
Charge regulator. The regulator collects and manages energy to keep it within certain safety limits.
Inverter or DC / AC converter.
The most used voltages in the photovoltaic field are 12 or 24 V.
The accumulator is generally made up of monoblocks. They can also be individual elements designed for deep and cyclical charges and discharges.
Automotive batteries are not recommended. Despite working properly, it has a low lifespan. In other words, they tolerate less charge and discharge cycles compared to accumulators designed for this type of use.
In the case of pole or height accumulation installations, car batteries cannot be used. Any electrolyte leakage could cause damage to people, animals and property. For example, in public lighting systems or the like.
In these facilities special accumulators are used in which the liquid electrolyte is replaced by a special gel.
Electric Charge Controllers
The charge controller is an electronic device and should automatically disconnect under the following conditions:
The voltage supplied by the modules is less than the minimum of the charge accumulators.
Full recharge. Derivation of the electric current generated directly to the inverter.
Total discharge. Battery now exhausted and possible bypass to the inverter.
Thermal Solar Energy
In autonomous systems, the combination of photovoltaic solar panels with solar collectors is also frequent. Solar collectors allow you to transform solar radiation into heat energy. These systems are used to obtain domestic hot water or heating. This is thermal solar energy.
Solar thermal energy is based on the use of solar energy by transforming it into thermal energy.