You would agree with me if I say that most people don’t know exactly how solar panels work. They may know that solar panels absorb the sunlight and turn it into electricity but they don’t know what is hidden behind this operation. What equipment is a part of this process? How solar cells can influence energy production etc.
This article will give you helpful material that will benefit you in the future when you plan to purchase solar panels.
Let’s begin by uncovering the small secrets of solar energy.
How does solar energy work?
First, solar panels collect sunlight. Solar panels gather sunlight with photovoltaic (PV) cells and produce direct current (DC) electricity.
However, most of our home electronics are using alternating current (AC) power, therefore, we need an inverter to convert electrical power from DC power to AC power.
After converting to the AC power, the power now is ready for your house using. If your solar panel cannot produce enough power for you to use, in most of the cases, you are connecting with the grid, and you can receive the power from the utility company.
On the other hand, if your solar panels produce more power than you need, you can send them back to the grid in order to get credit for your utility bills or you can have a solar battery to store the excessive energy.
Types of solar cells
So what are solar cells? They are constituent elements of solar construction (the total of solar panels, modules and cells) that transform light from the sun into electricity. There are 3 common types of solar or photovoltaic cells: crystalline solar cells (monocrystalline and polycrystalline) and thin-film solar cells. First, take a look at the difference between mono and poly cells.
Monocrystalline solar cells
1 The manufacturing process invented by the Polish chemist Jan Czochralski in 1916 includes the four sided cutting operation that makes the borders of a solar cell rounded. Regrettably, a lot of silicon is wasted during the stage of production. Therefore, the price of solar cells goes high and the environment may be polluted unless the waste is recycled.
2 The composition of a mono cell: a single ingot (or a crystal) of a very pure class of silicon sliced into wafers. It is the purity of silicon that makes transforming sunlight into electricity more efficient. Since mono panels are more effectual than poly cells, they produce more energy for the same space. So if your roof can’t accommodate a lot of panels, mono cells can save some space on a housetop.
3 Mono cells have the biggest lifespan because they tolerate heat better than other solar cell types. However, the performance retrogrades when the sun is burning the roof.
4 The color of mono cells is black that give them a uniform look that most people have a preference in.
5 Monocrystalline panels do produce more energy under the conditions of a weak sun in the late afternoon than polycrystalline panels.
6 If solar cells are coated with snow or dirt, they can break down unless you get micro-inverters.
Polycrystalline solar cells
1 The manufacturing process is newer as it was invented in 1981. There are 2 simple steps the process consists of: 1st step is to melt multiple chunks of silicon, 2nd step is to pour the melted silicon into a square shape. For this reason poly cells always have square edges. Barely any silicon is wasted therefore it makes it cheaper for a consumer to buy the panels. Additionally, the production method is very eco-friendly.
2 Poly cells are less efficient for the reason that they are made from a silicon that is not very pure. Besides, you will need more solar panels on your roof.
3 Poly cells are less tolerant to the heat. The heat may reduce the lifespan of a solar panel and it influences the efficiency in a negative way. Nevertheless, this is a minor problem and it is unlikely that the life expectancy of poly cells will notably go down.
4 The color of poly cells is blue. Bleaching can emerge on polycrystalline solar panels. Nine times out of ten people don’t find it aesthetic. The blue color is one of the reasons why the poly cells absorb less heat than the black mono cells.
Thin-Film Solar Cells (TFSC)
- Thin-film solar cells are made by placing a thin film of a base material onto a layer of a different material say plastic, metal or glass. For the reason of several levels, thin-film solar cells are much more heavy than crystalline solar cells.
- Thin-film solar cells are not as effective as crystalline solar cells and they require a larger space on your roof and a greater quantity of panels to reach the equal power output that crystalline solar cells have. This means that the price for PV-equipment will go up.
- Thin-film solar cells last a shorter period of time than crystalline solar cells that is why they come with a shorter warranty. Think if you want to invest in something that has a small return on investment.
- TFSC have a cheaper production cost and can be produced massively for a relatively good spending.
- The material of thin-film solar cells is quite flexible and you can’t really see the individual cells. There is no doubt that it will look elegant on your roof.
- Heat and a mild sun that covers only half of your roof in the late afternoon is not an issue for thin-film solar cells.
- Thin-film solar cells are used in a number of technologies that may involve as a first film the following materials:
- Amorphous silicon (a-Si)
- Organic photovoltaic cells (OPC)
- Cadmium telluride (CdTe)
- Copper indium gallium selenide (CIS/CIGS).
What are solar panels made of?
Besides solar cells, a solar panel is made of these following components:
- Solar cells
- Junction/ Connectors
The glass at the front can protect the silicon PV, the encapsulant binds all the parts of panels together and prevent the risks such as water and dirt of the cells. The backsheet protect the back part of the panel and the junction box transform the electricity which produces by the cells to the solar array.
What does a solar inverter do?
An inverter plays an important role in a solar system. Some people even think the inverter is the brain of the solar system. Typically, the inverter is doing the job that converts DC power into AC power which is commonly used in the commercial appliances.
Here are some different types of inverters that you need to know, to choose a correct type is important because it will affect the solar system’s output and efficiency.
- String inverters- The string inverter is often offered by the U.S. solar installation companies, it’s the less expensive option. This type of inverters is installed in rows that connected by strings or groups of solar panels.
Each string converts DC power into AC power, and each inverter controls multiple strings. It will work well if your solar panels don’t have shade at any point during the sunlight time.
- Micro-inverters- Micro-inverters are installed on each solar panel. The inverters transform DC power to AC power on the roof, therefore it doesn’t need to have a separate central inverter.
Moreover, you can track the performance form each panel, don’t need to worry about shaded, and you don’t need to have your solar panels face the same directions.
This type of the inverter is getting popular in the residential solar system and the price is getting lower and lower since it become a popular choice .
- Power optimizers- This type of inverters are also located in each solar panels, however, it collects DC power and sends the power to the string inverter. As the result, the efficiency is higher than string inverter.
On the other hand, power optimizer reduces the impact on the panel shaded part, and this type of inverter also let you can monitor the performance of the individual panels.
The price is between string inverter and micro-inverter, and it’s getting become one of the popular options for the residential solar system.
After knowing all the theory behind the solar panel, do you feel more comfortable to purchase your solar panel? If you still feel having questions, don’t worry, that’s why INSOLAR is here to help you. Check our website for more information and try our Solar Calculator, find a good quote for your home and it’s time to get ready to go solar!