The push for renewable energy sources has led to a surge in solar energy use. In the past decade alone, the solar industry grew by almost 50%, buoyed by federal support such as the Solar Investment Tax Credit and strong commercial and industrial demand for clean energy. 

As the solar sector continues to rise, it’s worth studying the backbone of the solar industry: solar panels.

This guide will illustrate the different types of solar panels available on the market today, their strengths and weaknesses, and which is best suited for specific use cases.

What is a Solar Panel?

Solar panels are used to collect solar energy from the sun and convert it into electricity.

The typical solar panel is composed of individual solar cells, each of which is made from layers of silicon, boron and phosphorus. The boron layer provides the positive charge, the phosphorus layer provides the negative charge, and the silicon wafer acts as the semiconductor. 

When the sun’s photons strike the surface of the panel, it knocks out electrons from the silicon “sandwich” and into the electric field generated by the solar cells. This results in a directional current, which is then harnessed into usable power. 

The entire process is called the photovoltaic effect, which is why solar panels are also known as photovoltaic panels or PV panels. A typical solar panel contains 60, 72, or 90 individual solar cells.

The 4 Main Types of Solar Panels

There are 4 major types of solar panels available on the market today: monocrystalline, polycrystalline, PERC, and thin-film panels.

Monocrystalline solar panels

Also known as single-crystal panels, these are made from a single pure silicon crystal that is cut into several wafers. Since they are made from pure silicon, they can be readily identified by their dark black color. The use of pure silicon also makes monocrystalline panels the most space-efficient and longest-lasting among all three solar panel types.

However, this comes at a cost — a lot of silicon is wasted to produce one monocrystalline cell, sometimes reaching over 50%. This results in a hefty price tag.

Polycrystalline solar panels

As the name implies, these come from different silicon crystals instead of one. The silicon fragments are melted and poured into a square mold. This makes polycrystalline cells much more affordable since there is hardly any wastage, and gives them that characteristic square shape.

However, this also makes them less efficient in terms of energy conversion and space, since their silicon purity and construction are lower than monocrystalline panels. They also have lower heat tolerance, which means they are less efficient in high-temperature environments.

Passivated Emitter and Rear Cell (PERC) panels

PERC solar panels are an improvement of the traditional monocrystalline cell. This relatively new technology adds a passivation layer in the rear surface of the cell that enhances efficiency in several ways:

• It reflects light back into the cell, increasing the amount of solar radiation that gets absorbed.

• It reduces the natural tendency of electrons to recombine and inhibit the flow of electrons in the system.

• It allows greater wavelengths of light to be reflected. Light waves over 1,180nm can’t be absorbed by silicon wafers and simply pass through, so they end up heating the cell’s metal back sheet and reduce its efficiency. The passivation layer reflects these higher wavelengths and stops them from heating up the back sheet.

PERC panels allow greater solar energy collection in a smaller physical footprint, which makes them ideal for limited spaces.  They are only slightly more expensive to produce than traditional panels, due to the added materials needed, but they can be manufactured on the same equipment, and can end up having a lower average cost per watt due to their efficiency.

To get a better feel for the benefits of PERC panels, check out our blog 5 Important Benefits of PERC Solar Panels You Need to Know.

Thin-film solar panels

Thin-film panels are characterized by very fine layers that are thin enough to be flexible. Each panel does not require a frame backing, making them lighter and easier to install. Unlike crystalline silicon panels that come in standardized sizes of 60, 72, and 96-cell counts, thin-film panels can come in different sizes to suit specific needs. However, they are less efficient than typical silicon solar panels.

Thin-Film Solar Panel Variations

Unlike crystalline panels that use silicon, thin-film solar panels are made from different materials. These are:

• Cadmium telluride (CdTe)

• Amorphous silicon (a-Si)

• Copper indium gallium selenide (CIGS) 

Cadmium telluride (CdTe)

CdTe has the same low-cost advantage as polycrystalline cells while possessing the lowest carbon footprint, water requirement, and energy payback time of all solar panels types. However, the toxic nature of cadmium makes recycling more expensive than other materials.

Amorphous silicon (a-Si)

Amorphous silicon panels (A-Si) derive their name from their shapeless nature. Unlike mono-and polycrystalline solar cells, the silicon is not structured on the molecular level. 

On average, an a-Si cell requires only a fraction of the silicon needed to produce typical silicon cells. This allows them to have the lowest production cost, at the expense of efficiency. This is why a-Si panels are suited for applications that require very little power, such as pocket calculators.

Copper indium gallium selenide (CIGS)

 

CIGS panels use a thin layer of copper, indium, gallium, and selenium deposited on a glass or plastic backing. The combination of these elements results in the highest efficiency among thin-panel types, though still not as efficient as crystalline silicon panels.

Solar Panel Types by Efficiency

Among all panel types, crystalline solar panels have the highest efficiency.

• Monocrystalline panels have an efficiency rating over 20%.

• PERC panels add an extra 5% efficiency thanks to their passivation layer. 

• Polycrystalline panels hover somewhere between 15-17%.

In contrast, thin-film panels are usually 2-3% less efficient than crystalline silicon. On average:

• CIGS panels have an efficiency range of 13-15%.

• CdTe ranges between 9-11%.

• a-Si have the lowest efficiency at 6-8%.

Highest (5% more than monocrystalline)

20% and up

15-17%

13-15%

9-11%

6-8%

Solar Panel Types by Power Capacity

Monocrystalline cells have the highest power capacity, thanks to their single-crystal construction that allows a higher output rating in a smaller package. Most monocrystalline panels can generate up to 300w of power capacity.

Recent advances in solar technology have allowed polycrystalline panels to bridge the gap. A standard 60-cell polycrystalline panel is now capable of producing between 240-300w. However, monocrystalline panels still beat polycrystalline in terms of power capacity per cell.

Because thin-film panels don’t come in uniform sizes, there is no standard measure of power capacity, and the capacity of one thin-film panel will differ from another based on its physical size. In general, given the same physical footprint, conventional crystalline panels output more power than a thin-film panel of the same size.

Solar Panel Types by Cost

Monocrystalline panels (or modules as they are technically known) carry a hefty price tag, due to its energy-intensive and inefficient manufacturing process with only a 50% yield for every silicon crystal. 

Polycrystalline modules are cheaper because they make use of the crystal fragments leftover from monocrystalline production, which results in a simpler manufacturing process and lower production costs.

Among thin-film solar panels, CIGS is the most expensive, followed by CdTe and amorphous silicon. Apart from the lower acquisition cost, thin-film modules can be easier to install thanks to their lighter weight and flexibility, which lowers the cost of labor.

While the total cost of residential systems has declined by more than 65% over the last decade, the soft cost of a system has actually risen from 58% of total system cost in 2014 to 65% in 2020.

For more information about soft costs, check out our article on the soft costs in the solar industry, and what’s being done to reduce them.

$0.32-$0.65

$1 – $1.50

$0.70 – $1

$0.60 – $0.70

$0.50 – $0.60

$0.43 – $0.50

Note that these figures don’t include the cost of installation and labor. With labor and other overhead factors, the total can rise to $2.50 to $3.50 per watt.

Other Factors to Consider

Temperature

The temperature of a solar panel can affect its ability to generate energy. This loss of output is reflected through the temperature coefficient, which is a measure of the panel’s decrease in power output for every 1°C rise over 25°C (77°F). 

Monocrystalline and polycrystalline panels have a temperature coefficient between -0.3% / °C to -0.5% / °C, while thin-film panels are closer to -0.2% / °C. This means that thin-film panels can be a good option for hotter environments or places that experience more sunlight throughout the year.

Fire rating

The updated International Building Code of 2012 requires solar panels to match the fire rating of the roof where they are installed. This is to ensure that the modules do not accelerate the spread of flames in the event of a fire. (California goes one step further by requiring the whole PV system, which includes the racking system, to have the same fire rating).

As such, solar panels now carry the same classification rating as roofs:

Class A

• effective against severe fire test exposure

• flame spread should not exceed 6 feet

• required for wildland-urban interface areas, or areas with high fire severity and wildfire risk

Class B

• effective against moderate fire test exposure

• flame spread should not exceed 8 feet

Class C

• effective against light fire test exposure

• flame spread should not go beyond 13 feet

Hail rating

Solar panels are also tested for hail impacts. 

UL 1703 and UL 61703 standards address hail storms, by dropping 2-inch solid steel spheres on solar panels from a height of 51 inches, and by firing 1-inch ice balls on PV panels with a pneumatic cannon to simulate hail impacts.

Because of their thicker construction, crystalline panels can withstand hail hitting at speeds of up to 50mph, while thin-film solar panels carry a lower rating due to their thin and flexible nature.

Hurricane rating

While there is no formal solar classification rating for hurricanes, the Department of Energy recently expanded its recommended design specifications for solar panels to safeguard against severe weather.

The new recommendations include: 

• Modules with the highest ASTM E1830-15 rating for snow and wind loading in both the front and back.

• Fasteners with true locking capability based on DIN 65151 standard

• The use of through-bolting modules with locking fasteners instead of clamping fasteners

• The use of 3-frame rail systems for improved rigidity and support against twisting

• Tubular frames over open-shaped C channels 

• Perimeter fencing around PV systems to slow down wind forces 

Light-Induced Degradation (LID)

LID is a performance loss commonly seen in crystalline panels during the first few hours of sun exposure. This happens when sunlight reacts with oxygen traces left over from the manufacturing process, which affects the silicon lattice structure.

The LID loss is directly tied to the manufacturing quality and can range from 1-3%.

Summary: Solar Panel Types Compared

Highest

High

Middle

Highest to lowest:

CIGS

CdTe

a-Si

Highest (5% more than monocrystalline)

20% and up

15-17%

CIGS: 13-15%

CdTe: 9-11%

a-Si: 6-8%

Black with rounded edges

Black with rounded edges

Blue with square edges

Depends on the thin-film variant

Requires least space

Most efficient

Highest power capacity

Less expensive alternative to PERC panels without the passivating layer

Middle option in terms of cost, efficiency and power capacity

Lowest cost

Easier to install

Most expensive initially

Some earlier panels suffered from light and elevated temperature induced degradation

High initial cost

Low yield in the manufacturing process 

Low heat tolerance, not suitable in hot environments

Shorter lifespan than crystalline panels requires

 more space

Least efficient

So, Which Solar Panel Type Should You Use?

As crystalline and thin-film panels have their own pros and cons, the choice of solar panel ultimately comes down to your specific property and condition settings. 

Limited Space

Those living in a dense area with limited space should opt for highly efficient monocrystalline modules to make the most of the physical space and maximize utility savings. If budget permits, going for PERC panels can lower energy generation costs even more in the long run.

Large Properties

Those with a sufficiently larger property can save on upfront costs by using polycrystalline solar panels, where a bigger panel footprint can offset the lower panel efficiency. However, a larger footprint could also mean added labor costs, so it’s not necessarily cheaper to get a higher quantity of less expensive panels. While the initial cost may be low, it may eventually be offset by reduced efficiency and higher operating expenses in the long term.

As for thin-film solar panels, these are best suited for locations where the heavy and labor-intensive installation of crystalline silicon is not feasible. Such locations can include commercial buildings with tight spaces or thin roofs; compact spaces such as recreational vehicles and watercraft; and areas that require flexible installation instead of rigid paneling. 

Keep in mind that solar panels are designed for long-term installation, which can be as long as 25 years. So whatever type you choose to go with, make sure to do your homework to ensure that it’s the best option for your needs.

To learn more about solar fundamentals subscribe to our blog.

How to Choose Solar Panels: Buying Guide & Best Options

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Choosing the best solar panels this 2023

Welcome to our comprehensive guide on choosing solar panels for your energy needs. In this article, we will provide you with essential tips and insights to help you make an informed decision. Additionally, we will introduce you to JOG International, a leading solar panel supplier that offers a range of buying guides and advantages to assist you in finding the best solar panel solutions.

In an era where sustainability and renewable energy are at the forefront of global conversations, understanding solar panels is more important than ever. These ingenious devices play a pivotal role in harnessing the abundant power of the sun and converting it into usable electricity.

Solar panels are marvels of engineering that utilize photovoltaic (PV) technology to convert sunlight into electrical energy. At their core, solar panels consist of numerous solar cells, typically made from crystalline silicon, which have the ability to generate an electric current when exposed to sunlight. This process, known as the photovoltaic effect, occurs due to the interaction of sunlight with the atoms in the solar cells.

When sunlight strikes a solar panel, it excites the electrons within the atoms of the solar cells, causing them to move and create an electric current. This flow of electrons is then captured and directed through the wiring within the panel, ultimately providing usable electricity for various applications. Whether it’s powering homes, businesses, or even charging electric vehicles, solar panels have revolutionized the way we generate and consume energy.

The importance of solar panels in sustainable energy generation cannot be overstated. By harnessing the power of the sun, we reduce our reliance on fossil fuels, decrease harmful greenhouse gas emissions, and mitigate the impact of climate change. Solar energy is a clean, renewable resource that is virtually inexhaustible, making it a vital component in transitioning towards a more sustainable and environmentally conscious future.

Additionally, solar panels offer numerous benefits on an individual level. By installing solar panels on rooftops or in dedicated solar farms, homeowners and businesses can generate their own electricity, thereby reducing their dependence on the traditional grid and potentially lowering their energy bills. Furthermore, many governments and utility companies provide incentives and net metering programs, allowing solar panel owners to sell excess electricity back to the grid, further increasing the financial viability of solar energy.

Factors to Consider When Choosing Solar Panels

As the demand for clean and renewable energy continues to rise, solar panels have become a popular choice for homeowners and businesses alike. However, with the wide variety of options available in the market, choosing the right solar panels can be a daunting task. JOG International will discuss the key factors to consider when selecting solar panels in 2023.

• Energy Requirements and System Size: Understanding your energy requirements is crucial when choosing solar panels. Evaluate your average electricity consumption and determine the size of the solar panel system needed to meet your needs. Consider factors such as the number of occupants, energy-intensive appliances, and future growth in energy demand. This analysis will guide you in selecting the appropriate panel capacity and system size.
• Efficiency and Performance: Solar panel efficiency refers to the ability of a panel to convert sunlight into electricity. Higher efficiency panels generate more power, making them ideal for limited roof space or locations with less sunlight. However, higher efficiency panels often come at a higher cost. Consider the balance between efficiency and budget to determine the best option for your specific requirements.
• Durability and Warranty: Solar panels are a long-term investment, so it’s essential to choose panels that are durable and come with reliable warranties. Look for panels made with high-quality materials and proven durability in different weather conditions. Additionally, check the warranty offered by the manufacturer, including coverage for defects, power output, and performance guarantees. A longer warranty period demonstrates the manufacturer’s confidence in their product’s quality and reliability.
• Type of Solar Panel: There are three main types of solar panels: monocrystalline, polycrystalline, and thin-film. Each type has its advantages and considerations:

Monocrystalline panels: These panels are made from a single crystal structure, offering high efficiency and sleek aesthetics. They perform well in limited space but tend to be more expensive.

Polycrystalline panels: These panels are made from multiple crystals and are more affordable than monocrystalline panels. They have slightly lower efficiency but are a popular choice for larger installations.

Thin-film panels: These panels are lightweight and flexible, making them suitable for irregular or curved surfaces. However, they have lower efficiency and require more significant installation space.

Consider your budget, available space, and aesthetic preferences when selecting the type of solar panel that best suits your needs.

• Certifications and Standards: Look for solar panels that meet recognized industry certifications and standards. Certifications such as IEC 61215 and IEC 61730 ensure that the panels have undergone rigorous testing for performance, durability, and safety. Additionally, check if the panels comply with local regulations and qualify for any government incentives or rebates.
• Cost Considerations: While cost should not be the sole deciding factor, it is an important consideration. Compare prices from different manufacturers and suppliers, keeping in mind the quality, efficiency, and warranty of the panels. Consider the long-term savings and return on investment that solar panels can provide, as they can significantly reduce or eliminate your electricity bills over time.

5 Buying Guides by JOG International

1. Solar Panel Selection Guide: JOG International’s expert guide walks customers through the selection process, explaining key considerations and helping them identify the most suitable solar panels based on their energy needs and budget.
2. Technical Specifications Comparison: This guide helps customers compare technical specifications, such as panel efficiency, wattage, and temperature coefficients, to make an informed decision. It provides a clear understanding of the performance differences between various solar panel options.
3. Financing and Incentives Guide: JOG International understands the financial aspects of solar panel installation. Their guide outlines available financing options, government incentives, and tax credits to help customers navigate the financial landscape and maximize savings.
4. Installation and Maintenance Assistance: JOG International provides valuable insights into the installation process and offers recommendations for reliable installation services. Additionally, they offer maintenance tips to help customers ensure the longevity and efficiency of their solar panels.
5. International Shipping and Support: As a one-stop solar shop direct from China, JOG International caters to customers worldwide. They offer reliable international shipping services and provide prompt customer support to address any queries or concerns.

Advantages of Choosing JOG International as a Trusted Solar Panel Supplier

• Wide Range of Products: JOG International offers a diverse range of high-quality solar panels, ensuring customers have ample options to choose from based on their unique requirements.
• Competitive Pricing: Benefit from JOG International’s direct sourcing from manufacturers in China, enabling them to offer competitive pricing without compromising on product quality.
• Quality Assurance: JOG International maintains strict quality control measures and works with reputable manufacturers, ensuring the panels meet international standards and certifications.
• Global Delivery: Enjoy the convenience of JOG International’s worldwide shipping services. No matter where you are, they will deliver your solar panels promptly and securely.
• Dedicated Customer Support: JOG International provides excellent customer support, assisting clients throughout the buying process, from product selection to post-purchase queries.

Conclusion

Choosing the best solar panels is a critical step towards harnessing clean and renewable energy. By following the buying guide provided and considering the advantages of JOG International, you can make an informed decision and benefit from high-quality solar panel solutions. By considering factors such as your energy requirements, panel efficiency, durability, type, certifications, and cost, you can make an informed decision that aligns with your goals and budget.

At JOG International, we offer a wide range of high-quality solar panels that meet international standards. Our team of experts can guide you through the selection process, ensuring you choose the best solar panels for your specific needs. Embrace the power of solar energy and contribute to a sustainable future.

Ready to explore the best solar panel options? Contact us today to explore our range of solar panels and start your journey towards clean, renewable energy.