Solar panels and Solar cells are two prevalent words in renewable energy space. And, you often wonder what the actual difference between them is!
Today, we are going to clear all the doubts in this article. The article will not go too technical, but it will give enough knowledge to understand the differences in detail.
So, what is the actual difference between Solar panels and Solar cells?
A solar cell is the building block of a photovoltaic system, which can convert solar or Photonic energy to electrical energy. In contrast, a Solar panel is a collection of multiple solar cells designed in a series and parallel connections to produce the desired voltage from the photovoltaic system.
In general, even a single solar panel is not enough to make enough energy to power an entire house or industry. In such scenarios, we use multiple solar panels to form a solar array.
Thus, starting from the Solar cell, which can produce around 0.5V energy, we can construct solar panels, followed by solar arrays that can produce energy even in Kilowatts.
In the following sections, we’ll discuss the critical differences between Solar panels and Solar cells in detail so that you can have a good understanding while working with them.
1. Fundamental Differences Between Solar Panel and Solar Cell
• Working Principle of Solar Cell
The Working Principle of a solar cell is wholly based on photovoltaic effects, which is generating potential difference at the junction of two different materials in response to the energy of photons.
The photovoltaic effect is closely related to the photoelectric effect, where electrons can be emitted from material by absorbing the energy of photons with a higher frequency than the threshold frequency of the material.
So, we can see this effect is converting one form of energy to another. Although only a minimal amount of energy can be converted in this process, we design the solar cells in a particular way to maximize the conversion without significant loss.
A solar cell is made of semiconductors like silicon. Silicon crystals are doped with Boron and Phosphorus to turn them into a P-type and N-type semiconductor, respectively. Next, those two types are put together so that they can form a PN Junction.
Now, you might wonder why so much work if we can eject free electrons by the photoelectric effect! Actually, by doing that, we can’t generate current as those free electrons have no specific directions to go.
That’s why using such formation of the solar cell; we can create a potential difference with the help of the photoelectric effect. Eventually, the potential difference will create an electric field, so now the free electrons can move towards a specific direction to generate current flow.
We hope now you have a good understanding of how Solar Cell works. In an upcoming section, we’ll explain solar cells’ construction in detail.
To know more about the working principle of Solar cells, you can visit here.
• Working Principle of Solar Panel
In general, a silicon solar cell can produce voltage around 0.5V – 0.6V. Sometimes it depends on the size of the solar cell, but most of the standard solar cells can produce that amount of voltage.
Now, with a single solar cell, we can’t even charge a calculator, so how can we power our entire house? Well, that’s where Solar Panels come forward to rescue!
If we add all the solar cells in a series combination, we can increase the total amount of voltage, keeping the current flow the same!
And if we connect them in parallel combination, the voltage remains the same between the terminals. However, we can increase the amount of current flow!
So using these two combinations, we can achieve our desired amount of output energy settings.
Most of the time, even a single solar panel is not enough to power an entire house. In such a case, we can add multiple solar panels in an array to generate more voltage!
• Output Voltage
A single silicon solar cell can produce voltage up to 0.5V to 0.6V. However, in solar panels, the number is high as 12V, 15V, 30V, 36V, and it depends on how many solar cells are used to form it.
Usually, the voltage output of a solar panel can be varied by various combinations of solar cells.
2. Construction Differences
• Construction of Solar cells
Solar cells are PN junction diodes with some specific design to make the photovoltaic effect effective.
In general, the top thin layer is made with an N-type semiconductor. And the bottom part is made of a P-type semiconductor, which is relatively thicker. The top layer is made thinner so that photons can easily reach out to the depletion region created in between P and N-type semiconductor junctions.
Also, the metal rings are placed on P-type and N-type material, which works as the electrodes to form the circuit.
• How to Construct Solar Panels
A PV system is used to convert solar energy to electrical energy. As we learned earlier, solar cells are the building blocks of a photovoltaic system.
However, a single solar cell is not enough to power an entire house. To counter this problem, we construct solar panels, in which we use a combination of 25 to 30 numbers solar cells to get an output voltage around 15V.
Even that is also not enough to power an entire house. In such a case, we create solar arrays with multiple solar panels.
One thing to mention, solar cells are not the only components to construct solar panels. Let’s check out all the components we have in a solar panel.
Components of Solar panels
- Anodised aluminum frame.
- Highly transparent tempered glass.
- Encapsulant material such as ethylene-vinyl acetate (EVA), polyvinyl butyral (PVB), and thermoplastic polyurethane (TPU).
- Photovoltaic solar cells
- Insulating back sheet.
These all are necessary components of a solar cell to maximize energy conversion and ensure protection from outside disturbances.
Purpose of Solar Array
To power your entire house, you need a group of solar panels. A group of solar panels is called a solar array. Usually, you can calculate how many solar panels you need according to your need.
As solar cells generate direct current, you need to connect an inverter to your whole solar array system to get alternating current for your usage.
Very often, we get confused between solar cells and solar panels. In this article, we learned solar cells are the building blocks of the entire photovoltaic solar system. Solar panels are the collection of solar cells to get the higher output voltage and protect the building blocks from outside disturbances.
As always, we are so proud of you for considering green living. You are making an impact by considering it.