What Are Solar Panels Made Of? Everything You Need to Know

What Are Solar Panels Made Of? Everything You Need to Know

Last Updated on January 19, 2024 by Jeremy Pearl
Dec 22

Solar panels are efficient, inexpensive, and accessible, but many people wonder how they work and how they provide renewable energy reliably and safely.

Here at Sandbar Solar, we’ve been helping customers throughout the Central Coast and the Greater Bay Area design and install solar arrays since 2004. We have hands-on experience with just about every kind of solar panel in existence.

In this guide, we’ll discuss how solar panels work, what they’re made of, and how they’re manufactured.

What Materials Are Solar Panels Made of?

what solar panels are made of

Solar panels are made of six primary components: silicon solar cells, metal frames, glass sheets, 12V wire, and bus wire.

Here’s a breakdown of each:

Silicon solar cells

Silicon solar cells transform sunlight into usable electricity. The cells are soldered together in a grid-like configuration and sandwiched between protective glass panels.

When sunlight penetrates the outer glass layer and strikes the silicon cells, the thin sheets of silicon interact with the incoming light and generate an electrical charge.

This charge can then be harnessed and converted into electrical power.

Metal frame

The metal frame surrounding a solar panel is a critical component that serves multiple purposes.

For one, it protects the panel from external conditions, including heavy rain, hail, or high winds.

The frame also makes the panel easier to mount and ensures that the panel can be positioned and secured at an optimal angle.

Glass sheet

Solar panels are typically encased in a layer of glass sheeting (about 6-7 mm thick) to protect the photovoltaic cells inside the panel, which are incredibly delicate.

In addition to protecting the cells, the glass allows optimal light penetration.

That said, the glass used in solar panel construction is different from the kind of glass that’s in your windows at home. Instead, it’s a highly durable variety often called solar glass.

Solar glass is specially constructed to withstand elements like hail, salty air near the ocean, and severe weather over time.

Solar glass is also designed to contain low iron levels, which helps enhance light transmission and ensure maximum efficiency in energy conversion.

12V wire

Another essential component of solar panels is standard 12V wire, which helps to regulate the quantity of energy the panel transfers to your inverter.

In doing so, this simple wire makes solar panels more sustainable and efficient.

Bus wire

Bus wire is an insulated wire used between connecting and leading wires.

In solar panels, bus wires typically connect the panel’s silicon solar cells in a parallel configuration.

These wires are thick enough to carry strong electrical currents and are easy to solder.

The Different Types of Solar Panels

While all solar panels contain the same essential ingredients, the following three types of solar panels are all manufactured differently:

1. Monocrystalline solar panels

polycrystalline solar panels

Monocrystalline solar panels are a type of solar panel produced from a single, large silicon block that’s transformed into silicon wafers. Monocrystalline panels are known for their distinctive black aesthetic.

Pros:

  • Higher Efficiency: Monocrystalline solar panels are characterized by their higher efficiency rates. This enables them to generate more power per square foot than other types.
  • Aesthetically Pleasing: The sleek black appearance of monocrystalline panels is visually appealing.
  • Heat Resistant: Monocrystalline panels retain their performance and efficiency better than polycrystalline panels, even in high-temperature conditions.
  • Space Efficiency: Due to their higher efficiency, you’ll need fewer monocrystalline panels to produce the same amount of power (as compared to polycrystalline panels), which means arrays made of this material require less space.
  • Durability: Monocrystalline panels are often more durable and have a longer lifespan than other types of solar panels, which may make them a better long-term investment.

Cons:

  • High Cost: Monocrystalline solar panels are typically a bit more expensive compared to other types of panels, thanks to the high-purity silicon used in their production.
  • Wasted Resources: Monocrystalline solar cells are cut from cylindrical ingots, which results in a significant amount of wasted silicon.
  • Performance Decreases in Shade: Monocrystalline solar panels perform poorly in shady or low-light conditions. The entire panel might stop producing electricity if even a small portion is covered by shade, although some solar panel manufacturers are developing solutions to address this (i.e., REC solar).
  • Temperature Sensitivity: These panels’ efficiency can drop if they get too hot, which is a possibility in intensely sunny climates.

Best for: Monocrystalline solar panels are best suited for situations where aesthetics are important, high efficiency is desired, and space is limited. They offer a clean and better-looking aesthetic for projects of any size. Thanks to their high-power output and longevity, they are ideal for residential and commercial buildings with small roofs.

2. Polycrystalline solar panels

polycrystalline solar

Polycrystalline solar cells are another type of silicon-based cells known for their blueish color.

Unlike monocrystalline cells, which are sliced from a large silicon block, polycrystalline cells are formed by melting and fusing multiple silicon crystals.

Pros:

  • Cost-Effective: Polycrystalline solar cells are generally less expensive to produce than their monocrystalline counterparts, making them more affordable.
  • Less Waste: Their production process results in less silicon waste, contributing to a more environmentally friendly manufacturing approach.
  • Temperature Tolerance: They perform relatively well in high-temperature conditions, unlike monocrystalline cells, which may experience efficiency losses.
  • Space-Efficient: Although polycrystalline solar cells have lower efficiency than monocrystalline cells, their square shape allows for efficient use of space when installing a solar power system.

Cons:

  • Lower Efficiency: Polycrystalline solar cells typically have lower efficiency rates compared to monocrystalline cells due to the many crystal structures in each cell. Due to lower efficiency, you may need more polycrystalline panels to generate the same amount of power, requiring more space.
  • Aesthetic Considerations: The bluish hue and less uniform appearance of polycrystalline panels may be less appealing to some homeowners.
  • Heat Tolerance: Polycrystalline solar cells tend to have a lower heat tolerance, meaning that their performance and efficiency can decrease more rapidly than other types in hot temperatures.

Best for: Polycrystalline solar cells are best suited for large-scale, cost-effective solar installations. Their lower efficiency is offset by their relatively lower cost, making them an optimal choice for large open spaces like solar farms. Additionally, due to their robust nature, they are a great option for areas with harsh weather conditions.

3. Amorphous solar panels

Amorphous silicon cells are used to create flexible solar panel materials typically utilized in so-called “thin-film solar panels.”

Unlike the other types of panels, amorphous silicon cells offer a thin, non-crystalline structure attached to material like glass, plastic, or metal.

This makes them less bulky than traditional panels and gives them their distinctive bendable qualities.

Pros:

  • Energy Efficiency: Amorphous solar cells are more efficient in cloudy or low-light conditions compared to their crystalline counterparts.
  • Flexibility: Due to their thin film structure, amorphous solar cells can be made flexible, opening up more possibilities for their application.
  • Cost-effective: The manufacturing process of amorphous solar cells is less energy-intensive, which makes them more cost-effective to produce.
  • Environmentally Friendly: These solar cells require less raw material in their production, resulting in a lower environmental impact.
  • Less Sensitive to Heat: Unlike crystalline solar panels, the performance of amorphous solar panels is less affected by high temperatures.

Cons:

  • Lower Efficiency in High Sunlight: Amorphous solar cells perform well in shady or cloudy conditions but will not keep up with other types of panels in sunny conditions. In fact, amorphous solar cells have a higher temperature coefficient, meaning their performance may actually decrease in high-temperature conditions.
  • Degradation: These types of solar cells experience a phenomenon known as the Staebler-Wronski effect, where their efficiency decreases over time, especially in the initial months of usage.
  • Less Durable: The thin film nature of amorphous solar panels can make them less durable and more prone to damage than crystalline solar panels.

Best for: Amorphous solar cells, due to their flexibility and lightweight nature, are ideal for a variety of applications. They are especially suitable as integrated power supplies for buildings and vehicles, thanks to their ability to conform to curved surfaces.

How are Solar Panels Made?

Solar panel production involves the following steps:

1. Building the solar cells

The foundational component of solar panels is the solar cells within them. Depending on the kind of cell being manufactured, the cells are made by mixing crystalline silicon, gallium, or boron to generate silicon ingot.

Next, phosphorus is added to the silicon ingot, which allows the cells to transmit and conduct electricity.

Finally, the silicon ingot is sliced into thin wafers. The wafers are then coated in an anti-reflective material, and narrow slits are cut into them to direct the flow of electricity.

2. Creation of the solar panel

Once the silicon wafers are complete, the solar cells are soldered together.

To create a standard-sized solar panel, 60-cells or 66-cells will be soldered together.

For larger panels, most frequently involved in commercial projects, up to 96-cells may be soldered together.

3. Installation of additional components

Next, the back sheet, front glass layer, and frame are added to the solar panel.

Here’s the process:

  • First comes the back sheet (typically black or white in color), which is usually made from strong, durable plastic and is added to the bottom of the solar cells, where it functions to protect them.
  • Next, the solar manufacturer covers the solar cells with a thin glass sheet, which filters sunshine.
  • Finally, the parts are all secured with ethylene vinyl acetate (EVA) glue and confined within a metal frame, which includes the latches needed to mount the panel to your roof.

4. Junction box installation

Now, it’s time for the solar panel manufacturer to add the junction box.

This critical feature protects the wiring system of the solar panel and allows the panel to move electricity to the inverter.

It also prevents electricity from reversing direction, which is important because when the panel isn’t producing electricity, it will attempt to consume it, instead.

The junction box prevents this, which allows the panel to function properly.

5. Testing

Once the panels are complete, they’re tested according to Standard Test Conditions (STC). This process verifies that the panels meet their stated output and efficiency levels and that they’re functioning properly.

Specifically, the panels are placed in a flash tester that simulates the following standard conditions: 1000W/m2 irradiance, 25°C cell temperature, and an air mass of 1.5g.

The cells that pass the testing phase are ready to be shipped out to customers and installed.

How Solar Panels Work

Solar panels convert sunlight directly into electricity. These panels are composed of numerous individual solar cells, each made of silicon.

Here’s how the solar panels, and the cells within them, work:

  • When sunlight strikes the panels, the solar cells absorb the energy.
  • This absorption of sunlight energy excites the electrons in the solar cells and creates an electrical flow – this process is known as the “photovoltaic effect.”
  • The metal casing and wiring of the silicon cells allow the electrons in the solar cells to move freely and supply power.

To learn more about how solar panels work, check out our comprehensive guide.

Ready to Install Your Energy-Saving Solar Array? Sandbar is Here to Help!

There’s no time like now to go solar!

In addition to saving you energy and helping avoid outages, installing a solar array on your home allows you to embrace energy independence and position yourself for a greener future.

Ready to take the first step? Contact Sandbar Solar today to get an estimate. 

FAQs

1. What is the best solar material?

Monocrystalline solar panels are known to be the most efficient and offer the highest power capacity. That said, the right solar material for your applications depends on a variety of factors, so we recommend talking to a solar installer to find out what material is ideal for you.

2. Are solar panels environmentally friendly to make?

Solar panel manufacturing has evolved in recent years and continues to strive to become as green as possible. That said, manufacturing anything – solar panels included – requires resources and energy. Fortunately, many solar panels are being recycled nowadays, and the materials used to make them are being repurposed.

3. Are solar panels safe?

As long as they’re used as intended, solar panels are perfectly safe. However, solar panels do contain chemicals like lead and cadmium, which can be dangerous if the panel is broken or improperly recycled at the end of its usable life cycle.

4. How long does it take for a monocrystalline solar panel to produce the energy required in the production and manufacturing process?

The energy payback time (EPBT) for monocrystalline solar panels depends on several factors, such as the geographical location where they are installed, manufacturing energy costs, and operational efficiency. On average, it typically takes about 1.5-3 years for a monocrystalline solar panel to generate the equivalent amount of energy that was used in its production and manufacturing process. This means that for the majority of their 25-30 years lifespan, these solar panels are producing ‘free’ energy, making them a sustainable energy solution.

About the Author

Jeremy has worked in the solar industry since 2006. He has a Bachelor’s Degree from UC Santa Cruz in Environmental Studies. Jeremy has spent most of his solar career in residential sales and Sales Management in both California and Hawaii. He was raised in Santa Cruz County and is passionate about helping local residents make the switch to clean and reliable renewable energy. Jeremy lives on the Westside with his wife and two boys and enjoys music, photography and hiking in his personal time.