What are solar panels?
Solar “panels” are more precisely photovoltaic (PV) modules. PV modules are a stack of engineered layers designed to do two things:
- Convert light to electricity
- Survive outdoors for decades
What solar panels are made of
Crystalline silicon (c-Si) modules are most commonly used today. A typical c-Si module is built with tempered solar glass on the outside and a clear polymer adhesive encapsulant. The encapsulant is typically EVA (ethylene-vinyl acetate) or sometimes POE (polyolefin elastomer). There’s also usually a backsheet (polymer) or rear glass, plus interconnects, frame and junction box.
Main materials in a typical home solar panel
If you strip away the industry jargon, here’s what a homeowner really needs to know about what solar panels are made of:
- Glass is the big part. It’s usually tempered, low-iron glass (similar strength to car windshields), recyclable and extremely durable. This is the largest component by weight, according to the National Renewable Energy Laboratory (NREL).
- Silicon is the part that turns sunlight into electricity. It’s usually refined silicon made from sand. This accounts for about 5% of a solar panel’s weight.
- Plastic encapsulants and backsheets seal the silicon cells so that moisture and air can’t get in. These layers are why panels last as long as they do (about 25 years).
- Aluminum framing is there for structural support. It’s also lightweight and recyclable.
- Copper wiring (and a small amount of silver) moves electricity out of the panel efficiently. The silver content is less than a gram per panel.
Did you know?
Silicon is one of the most plentiful materials available and affordable to create solar panels. However, manufacturing silicon involves significant processing.
How are solar panels manufactured?
Solar panels are a lot like a sandwich. Manufacturers layer glass, encapsulant, cells and a backsheet (or another sheet of glass), then laminate the stack under heat and pressure. The cells are made with a positively charged layer of silicon and a negatively charged layer to create an electric field.
Typical solar panel installation costs $12,600 to $33,376 in 2026.
The cells are then joined together with wire to make one big piece on top of the polymer material. A layer of glass tops off the sandwich.
After the panel is done, a junction box and wiring are added to the solar panel. Finally, everything is put into a frame, and the mounting assembly is attached.
Types of solar panels
Panels are separated into types depending on the way the silicon is used:
- Monocrystalline solar panels: These use a single silicon crystal for each cell. These are the most efficient type of panels but usually cost more.
- Polycrystalline solar panels: Made from multiple silicon crystals in each cell, these panels are cheaper because they are easier to produce. They are a little less efficient than monocrystalline panels, though.
- Thin-film solar panels: These inexpensive panels are made from layers of silicon. They are lightweight and typically used for smaller solar projects, not whole-home usage.
Additional solar panel subclassifications
Solar panels are divided into two subclassifications due to how they are constructed.
- PERC: PERC solar panels are monocrystalline or polycrystalline panels with a layer of material on the back of the silicon that bounces sunlight back through the panel to make it more efficient.
- Bifacial: Bifacial panels are mounted laterally and have solar cells on both sides. Think of this panel like two back-to-back sandwiches.
How solar panels work
Solar panels collect radiation from the sun and turn it into energy that your home can use. The cells in the panel absorb the light, and the energy created by the light interacting with the electric fields from the cells is converted from DC to AC using a solar inverter.
From there, it’s pumped into your home’s electric system or stored in a solar battery. You can learn more about the process by checking out our guide on how solar energy is made.
» DISCOVER: How is solar energy stored?
End-of-life recycling
Today’s solar panels have an average lifespan of 25 to 35 years, but it’s important to consider what happens to them after they’re no longer usable. Multiple facilities across the United States recycle silicon and cadmium telluride photovoltaic modules.
Unfortunately, the cost of recycling solar panel parts is still currently higher than the cost of disposing of them in a landfill, but technological innovations will help the U.S. Department of Energy (DOE) Solar Energy Technologies Office (SETO) improve end-of-life recycling.
FAQ
How much do solar panels cost?
The average homeowner spends $19,873 on solar panels. Depending on system size and location, average solar panels cost range from $12,600 to $33,376 in 2026.
Are there harmful or toxic materials in solar panels?
Common residential panels do not contain dangerous levels of toxic substances. For standard residential panels (crystalline silicon):
- No hazardous chemicals are exposed.
- Materials like lead or silver exist only in trace amounts and are fully sealed.
Where is the best place to buy solar panels?
If you want solar panels installed on your roof by professionals, the most common and easiest way is through a solar company that handles panel selection, engineering, permitting, installation and warranty support.
Where do materials for solar panels come from?
The major material, silicon, is made from sand melted at high heat. Metals that are used to make the panels, such as indium, cadmium, germanium, gallium, tellurium and selenium, are byproducts of the production of other metals.
How long do solar panels last?
Solar panels can last 25 years or more. Even after 25 years, most can still produce 80% of the power they could produce when they were brand new.
Article sources
ConsumerAffairs writers primarily rely on government data, industry experts and original research from other reputable publications to inform their work. Specific sources for this article include:
- U.S. Department of Energy, “Solar Photovoltaic Manufacturing Basics.” Accessed Feb. 13, 2026.
- U.S. Department of Energy, “Crystalline Silicon Photovoltaics Research.” Accessed Feb. 13, 2026.
- NREL, “Solar Photovoltaic (PV) Module Facts and Trends.” Accessed Feb. 13, 2026.
- U. S. Department of Energy, "Homeowner’s Guide to Solar.” Accessed Feb. 13, 2026.
- Center for Sustainable Energy, “Solar Energy Adoption: Information for Homeowners and Small Businesses.” Accessed Feb. 13, 2026.
- American Solar Energy Society, “Monocrystalline vs Polycrystalline Solar Panels.” Accessed Feb. 13, 2026.
