In 2019, a regular U.S. household located in the residential area had an average electricity consumption of about 909 kWh per month. This is due to the fact that most devices used today (mainly house appliances), are all using electricity to run: appliances such as: water heaters, washers and dryers, lights, refrigerators, TVs, computers, and among all these devices the water heater consumes the most power.
While these appliances help us do our chores and work faster and easier, we can’t deny the fact that every time we use them, we have to consume electricity which will increase our electricity bill month after month.
This is the main reason why many homeowners have decided to use solar panels to reduce the energy consumption from the grid and pay less on energy bills.
Are Solar Panels A good Investment Today?
According to statistics, solar panels are a good investment today, because they both protect the environment and can lower our energy bills.
The money saved while using a solar PV system depends on the area where you live, the number of sun hours received by the panels, as well as the size and the angle of the roof used to install the PV system.
Nevertheless, solar panels can generate free and clean electricity and they represent a wise investment today because they can help you save money.
Types of Solar Panels
If you decide to install solar panels to power your home with renewable energy, you should know that there are three types of solar panels used today, such as: monocrystalline, polycrystalline (multi-crystalline), and thin-film.
These types of solar panels differ in performance, aspect, price and installation requirements.
Depending on your area, you will use solar panels that will suit you best to maximize the amount of clean power produced by your PV (photovoltaic) system.
Monocrystalline Solar Panels
Monocrystalline cells were first industrialized in 1955, and as the name suggests, a monocrystalline solar panel is a panel that uses monocrystalline solar cells that have a black or dark blue color.
These photovoltaic cells are manufactured using a silicon ingot. To make the ingot, silicon rocks are melted at 2,500°F (1,371°C).
A seed crystal is then lowered into the melted silicon and slowly pulled out while spinning to produce a silicon ingot. Due to the fact the silicon ingot obtained this way has a round shape, a lot of material will be wasted when the silicon wafers will be cut into the required square shape.
The monocrystalline solar cells produced this way will be installed on a panel to produce a monocrystalline solar panel.
Monocrystalline solar panels are known to be one of the oldest, the most efficient, and the most reliable PV panels available on the market today. These solar panels are highly efficient because the solar cells are made from a single silicon ingot and not from pieces of silicon.
This type of solar panel has several advantages and disadvantages.
Pros of Monocrystalline Solar Panels
- The efficiency rate of this type of solar panel is about 20% since they are made using a single silicon ingot of high purity.
- Monocrystalline solar panels are very popular today due to their durability (over 25 years) and the performance provided by the photovoltaic cells.
- This type of solar panel is mainly used in urban areas because it does not take up too much space for energy production. Regardless of the space occupied by the panel, they always have a higher energy efficiency.
- Monocrystalline solar panels are also environmentally friendly because they reduce the amount of power drawn from power plants burning fossil fuels.
Cons of Monocrystalline Solar Panels
- Monocrystalline solar panels are produced using a single silicon ingot, which increases the production costs of these photovoltaic and this is reflected in their final price, which is usually higher compared to other types of solar panels.
- Despite being long-lasting and durable, it should be remembered that the panels themselves are fragile and are prone to damage. This is the reason why they are covered with safety glass to give them some protection.
- When installed in areas with low temperatures, in full shade of in rainy/snowy weather conditions, these panels won’t work well.
Polycrystalline Solar Panels
Polycrystalline solar panels use polycrystalline solar cells that are manufactured in a different way (in comparison with monocrystalline solar cells).
Silicon rocks are melted at the same temperature of 2,500°F (1,371°C), to produce a square shape quartz mold.
Polycrystalline solar cells have a blue mottled look (something similar to a piece of particle board) because they are made from multiple pieces of silicon pressed together.
They look like this because when the melted silicon is cooled and hardened, it crystallizes (like frost on a window).
When cut into wafers, less material is wasted, which means that the manufacturing process of polycrystalline solar cells is less expensive (compared to the manufacturing process of monocrystalline solar cells).
With an efficiency between 14 and percent, polycrystalline solar panels are usually installed on roofs that have plenty of space for solar. Polycrystalline solar panels are also used by large solar farms where is plenty of room for installing a large amount of solar panels.
These PV panels are also used by off-grid homes, to power traffic lights, street lights, and in many other applications because they are more affordable.
Pros of Polycrystalline Solar Panels
- Polycrystalline solar panels are cheaper in contrast to monocrystalline solar panels because their manufacturing process is less complex.
- Despite being more affordable, polycrystalline solar panels are pretty durable and they can work well for about 25 years.
- It also gives a positive environmental impact because the silicon waste produced during the manufacturing process is smaller compared to other types of solar panels.
Cons of Polycrystalline Solar Panels
- Since the purity of the polycrystalline solar cells cannot match the purity achieved by the monocrystalline solar cells, their efficiency is relatively lower (between 14 and 18%), which means that they diminished capacity to produce electricity from the sunlight.
- When installing a PV system using polycrystalline solar panels, we have to use more space on the roof or in the yard to achieve the same energy output of a PV system using monocrystalline solar panels. This difference in efficiency can be found in the price of the polycrystalline solar panels, which is usually smaller.
- Polycrystalline solar panels perform worse than monocrystalline panels when installed in areas with high temperatures.
The high temperatures can also affect the lifespan of these panels.
Thin-film Solar Panels
The manufacturing process of thin-film solar panels begins with a very long, but very thin role of plastic (about 30 microns in thickness).
The role of plastic goes through a sequence of deposition machines to put down first a back metal contact followed by the semiconductor amorphous silicon (six layers of amorphous silicon), which makes the solar cell itself.
Over the semiconductor material, a top conductive and transparent layer is installed to protect the amorphous silicon.
From there, the film is loaded onto a laser scribing machine that uses laser heads to scribe the material intersections, which makes up the individual solar cells on the film roll.
The next step involves loading the film onto a printing machine where electrical insulators are printed between the individual solar cells in order to isolate the positive and negative sections of the solar panel.
The film will then run through a silver printing machine that will print conductive silver ink particles to increase the electrical conductivity of the panel and then the copper busbar will be put on the film.
The final step involves putting the laminate (a Teflon type product) on the front surface and the back surface of the film to protect the solar panel from the outside environment.
Thin-film panels can be up to 20 times thinner compared to mono or polycrystalline panels.
The semiconductor material used can be amorphous silicon (a-Si), cadmium telluride (CdTe), copper indium gallium selenide (CIGS) or gallium-free (CIS).
A flexible solar panel can power boats, campervans, motorhomes, caravans, truck campers, fifth-wheel trailers, bikes, and many others.
Pros of Thin-film Solar Panels
- Involving lower costs in the manufacturing process, thin-film solar panels can be produced on a large scale, which makes them more affordable compared to crystalline-based solar cells.
- Thin-film solar panels come with a certain color and design which makes them more aesthetically appealing.
- Thin-film solar panels are made using flexible materials, which means that they can be used on a variety of devices (they are more practical than crystalline panels).
- This type of solar panels are not very affected by shade which means that they can generate power a longer period of time during the day.
Cons of Thin-film Solar Panels
- Thin-film solar panels have lower efficiency, and this means that we have to cover a larger surface with panels, which will increase the installation costs due to the use of additional support structures and cables.
- Compared to monocrystalline or polycrystalline panels, thin-film solar panels are likely to be damaged faster and this is the reason for the shorter warranty of these panels.
Conclusion
Each type of solar panel available today on the market has its unique characteristics that work well in certain environments, and this is the reason why you need to work with professionals when installing a new solar PV system to lower your bills and the carbon footprint of your home.
