Solar panels have been hailed as a viable alternative energy source for decades for many applications. However, how do they function, and the role of electrons in their working? This article is the perfect guide to answer this.
Here is what you are about to learn regarding the role of electrons in solar panels:
- Role of photons.
- Electrons in working of a solar panel.
- Conversion of solar energy into electricity.
- Solar system design.
- Efficiency of solar panels.
What Are Solar Cells Known as and Why?
Solar cells are also called photovoltaic (PV) cells. They are called so because the term ‘photovoltaic’ literally means light i.e. photo and electricity i.e. voltaic.
These cells generate electricity through the photovoltaic effect. This effect basically causes the generation of free electrons from the semiconducting silicon material of the solar panel when sunlight hits its surface.
This conversion process, as efficient as it is, creates no hazardous waste or emissions, making it a clean, green, and efficient source of energy. When light strikes on a photovoltaic cell, it creates DC power.
Where Do Electrons in a Solar Panel Come From?
To answer this we first need to look at the different materials solar panels are made of. The material used for the construction of solar panels needs to be a semiconductor material that allows maintaining a persistent flow of electricity.
Most of the solar panels these days are made of crystalline or amorphous silicon. Other less common materials for manufacturing solar panels include gallium arsenide or soluble platinum.
However, approximately 95% of the solar panels are manufactured with semi-conducting silicon material that has a lot of potentials to lose electrons out of the outer atomic shell as they are mostly unstable.
Basically, the electrons in a solar panel come from the material it is manufactured with. The basic morphology and atomic structure of the material is an important aspect to understand how electrons are generated in solar panels.
See also: What Are Solar Panels? (How They are Made)
What is the Association Between Electrons and Photons?
Electrons can be easily knocked out of the atoms of the semiconducting silicon material when photons i.e. light particles hit the surface of solar panels.
When these photons hit the solar panel surface, their energy is the source of generating free electrons within the panel.
These knocked-out electrons are then streamlined into a consistent pathway to generate a constant flow of electricity.
How Do Electrons Work In a Solar Panel?
First, we need to remember the basic concept of how we get electricity. Simply Speaking, electricity is generated when electrons from one atom move to another along a streamlined path.
A Solar Panel requires an electric field to function effectively and an electric field is created when opposite charges i.e. positive and negative, are separated.
To capture the energy of the electrons once they are free from the semiconducting silicon, they need to be streamlined into a proper pathway where they can move in a single direction to provide a direct current of electricity.
Manufacturers of solar panels achieve this by using two slightly differing layers of silicon and combine them with different materials. In the top silicon layer of the solar panel, phosphorous is added and this gives a negative charge to this layer.
Contrary to this, boron is added in the bottom silicon layer of the solar panel which results in a smaller quantity of electrons in this layer and hence puts a positive charge on it.
These alternating silica layers assist in establishing an electrical field at their junction.
What Exactly Happens to The Free Electrons In The Solar Panel?
The electrons are all pulled in the same direction i.e. towards the positive charge because they all have the same negative charge.
The silver lines on a solar panel represent the pathways electrons take as they move back and forth into each piece of silicon.
The electrical field established at the junction of the alternation silica layers generates free electrons when photons from the incoming solar radiation hit the surface of the solar panel and knock out the electron from its atomic shell.
These free electrons are transformed to useable electricity by a small number of supplementary apparatus of the cell.
The electrons are hurled together and are then sent to wires by the metal conductive plates present on the sides of the panel. These electrons can then flow without any reservations.
Can Solar Panels Lose Electrons?
A very simple and basic answer to this would be No, solar panels cannot lose electrons, and here’s why. This is because solar panels function by releasing electrons from the semiconductor elements within the cell, which create a circuit, and then these electrons are returned to the panel’s semiconductors.
The electrons travel through a closed-loop as an electrical current. “Electrons cannot be formed, destroyed, worn out, or vanished in circuits. They just circulate in a loop.”
When the solar panel and its supplementary components are exposed to sunlight, the complete device creates an electrical circuit that establishes a unidirectional flow.
The spent electrons continue to travel through the electrical circuit until they reach the solar cell’s backside, where they recombine with the holes they created when they left.
The solar panels never deplete out of electrons as a result of this. They are constantly flowing around and around the solar panel’s generated circuit.
Photons from the sun produce a voltage potential by releasing part of their energy in the circuit’s load. This then flows back into the solar cell, and the process continues indefinitely, evidently in the presence of sunlight.
Do Solar Cells Have Only Moving Parts?
Solar cells do not use any chemical processes or require fuel to generate electricity, and they do not have any moving components.
The only moving element in a solar panel is the electrons that move to maintain a constant flow among a set pathway to generate electricity.
The movement of these electrons is limited within the solar cell and the solar cell does not require any external moving parts for its functioning and generation of electricity.
How is A Solar System Arranged?
Solar cells are structured into groups, which is a large arrangement of cells. This structure, made up of tens of thousands of individual solar cells, acts as a central power source, converting sunlight into electrical energy and distributing it to industrial, commercial, and domestic consumers.
Domestic users mostly prefer designs that employ considerably smaller established systems on the top of their roofs to replace or supplement their traditional power source.
In many isolated terrestrial places where conventional electric power sources are either unavailable or excessively expensive to build, solar cell panels are also utilized to generate electricity.
Solar cells power most space facilities, from communications and weather satellites to space stations, because they do not have moving components that need to be maintained or fuels that need to be replenished.
What Type of Solar Panels Are Most Efficient and Why?
There are currently three types of solar panels available in the market that are:
- Monocrystalline
- Polycrystalline
- Thin-filmed
Among these, monocrystalline solar panels are known to be the most efficient among all others.
This is because the solar panels made of monocrystalline silicon, also known as single-crystalline cells, are manufactured with the purest form of the material.
To make a lengthy rod, a complicated procedure is used to create a crystal of this kind of silicon. After that, the rod is sliced into wafers, which are used to manufacture solar cells.
When compared to the other two kinds of solar cells, monocrystalline solar panels are known to have the best efficiency in normal test settings.
The present monocrystalline solar panel efficiency is between twenty-two to twenty-seven percent.
Do Solar Panels Deplete?
Although solar panel efficiency is higher than it has ever been, the amount of power that the panels can create continues to decrease with time.
Solar panels of high quality deteriorate at a rate of around 0.5 percent each year, providing twelve to fifteen percent less electricity at the end of their twenty-five to thirty-year lifespan.
What, however, are the causes of solar panel deterioration? What factors influence the pace at which solar panels deteriorate? Solar panels deteriorate over time due to regular wear and tear caused by UV radiation and unfavorable weather conditions.
Microcracks that develop in the silicon of the solar cells are also one way that solar panels degrade.
Electrical connections weaken as a result of these microscopic fractures, resulting in fewer pathways for those electrons from the sun to take, and therefore less energy reaching your inverter and into your house, company, or farm.
Junction box adhesion problems and discoloration are also concerns.
It’s a challenging topic to tackle since panels can deteriorate in a number of ways due to a variety of circumstances.
Solar panel manufacturers are continuously improving and finding new ways to minimize deterioration rates so that your panels can continue to provide power. In the meanwhile, your panels are will deteriorate at or below a certain pace, ensuring that your investment is secure.
Sources;
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