How do solar panels work? Solar power explained
Solar panels may seem complicated—we'll make it simple.
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You probably already know that solar panels use the sun's energy to generate clean, usable electricity. But have you ever wondered how they actually do it?
At a high level, solar panels are made up of solar cells, which absorb sunlight. They use this sunlight to create direct current (DC) electricity through a process called "the photovoltaic effect." Because most appliances don't use DC electricity, devices called inverters then convert it to alternating current (AC) electricity—the form that your home can use. This is the electricity that ultimately saves you money on electric bills.
Don't worry—we're not here to overwhelm you with the nitty-gritty details. But if you want to understand how solar panels create electricity a bit more, we'll explain what you should know.
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Key takeaways
Solar cells are typically made from a material called silicon, which generates electricity through a process known as the photovoltaic effect.
Solar inverters convert DC electricity into AC electricity, the electrical current appliances run on when plugged into a standard wall socket.
Other types of solar technology include solar hot water and concentrated solar power. They both use the sun's energy but work differently than traditional solar panels.
Solar energy is the light and heat that come from the sun. To understand how it's produced, let's start with the smallest form of solar energy: the photon.
Photons are waves and particles created in the sun's core (the hottest part of the sun) through a process called nuclear fusion. The sun's core is a whopping 27 million degrees Fahrenheit. This extreme temperature and pressure causes hydrogen atoms to collide and fuse, creating helium. The reaction releases massive amounts of energy in the form of photons.
This process is constant. Over 500 million tons of hydrogen atoms are converted into helium every second, resulting in photons that generate solar energy here on Earth.
In a nutshell, solar panels generate electricity when photons (those particles of sunlight we just discussed) hit solar cells. The process is called the photovoltaic effect.
First discovered in 1839 by Edmond Becquerel, the photovoltaic effect is a property of certain materials (known as semiconductors) that allows them to generate an electrical current when exposed to sunlight.
About 95% of solar cells are made from the element silicon, a nonmetal semiconductor that can absorb and convert sunlight into electricity. Here's how it works:
Solar cells have two layers of silicon. Each one is specially treated, or "doped," with phosphorus and boron to create the positive and negative sides of the solar cell, respectively. When photons hit the solar cells, they create an electric field at the junction between the layers.
This electric field knocks electrons loose from the atoms in solar cells, setting them in motion.
The electrons flow through the solar cell and out of the junction, generating an electrical current.
Metal plates on each side of the solar cells capture the electrical current and transfer it to connecting wires.
The electrical current flows through the wires to a solar inverter (or multiple inverters), which converts it to usable electricity for your home (more on this part below).
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While silicon is the most common semiconductor used in solar panels, alternative options exist.
Thin-film solar cells are a broad category of solar cells made from lightweight and often flexible materials. There are four main types: cadmium telluride (CdTe), amorphous silicon (a-Si), copper indium gallium selenide (CIGS), and gallium arsenide (GaAs). The light-absorbing layers in thin-film cells are about 350 times thinner than those in standard silicon cells, hence the name.
Organic solar cells are a type of thin-film cell that use carbon-based materials as semiconductors. Sometimes called "plastic solar cells" or "polymer solar cells," they're produced by dissolving organic compounds in ink and printing them onto thin plastics.
Perovskite solar cells are a third type of thin-film solar cells built out of perovskites, a class of man-made materials with a unique crystallographic structure that makes them highly efficient at converting photons of light into usable electricity. Perovskite cells are built using "solution processing," the same technique used to print newspapers. What makes perovskites especially promising is their ability to be layered on top of standard silicon cells, forming what researchers call "tandem" cells. These dual-layer devices capture a wider range of the solar spectrum—the perovskite layer absorbs high-energy visible light, while the silicon layer captures lower-energy infrared light. The result is efficiency that far exceeds what either material could achieve alone. LONGi Solar achieved a certified 34.85% efficiency in 2025, verified by the National Renewable Energy Laboratory (NREL)—compare that to the 20–23% you'd expect from a standard commercial silicon panel.
A typical solar module includes a few essential parts:
Solar cells: These do the heavy lifting, absorbing sunlight and generating electricity. Most silicon solar cells are either monocrystalline or polycrystalline. Monocrystalline cells are made from a single silicon crystal, while polycrystalline cells are made from silicon fragments. Monocrystalline cells give electrons more room to move, which translates to higher efficiency (and higher-priced panels).
Glass casing: Provides durability and protects the solar cells from the elements.
Insulation layer and back sheet: These are under the glass exterior and protect against heat buildup and humidity inside the panel, both of which can reduce solar panel performance.
Anti-reflective coating: Maximizes how much sunlight the cells can absorb instead of bouncing away.
12V wire: Regulates the amount of electricity transferred to your inverter.
Bus wire: Connects silicon solar cells and carries the electrical current between them.
Generating an electric current is the first step in the process of a solar panel’s working, but the process doesn't end there. Here's how a solar array creates a complete, usable electricity system for your home:
We've mainly focused on photovoltaic (PV) solar because it's the technology most homes and businesses use to generate clean electricity. But two other types of solar technology are worth knowing about:
Solar hot water heater
Solar hot water systems capture thermal energy from the sun and use it to heat water for your home—no electricity needed. These systems include collectors, a storage tank, a heat exchanger, a controller system, and a backup heater.
In a solar hot water system, there's no movement of electrons, and no creation of electricity. Instead, the solar panels, known as "collectors," transform solar energy into heat. Sunlight passes through a glass covering and strikes an absorber plate, which captures solar energy and converts it to heat. That heat is transferred to a fluid (either antifreeze or water) running through small pipes in the plate, which eventually heats the water in your tank.
Concentrated solar power
Concentrated solar power (CSP) also starts by converting sunlight to heat, but then takes it a step further. CSP technology uses mirrors to focus sunlight onto a single point, generating intense heat that drives a steam turbine to produce electricity.
CSP is primarily used in utility-scale installations—large power plants that feed electricity into the grid. It serves as a renewable alternative to fossil fuel-based power plants and can pair with thermal storage systems to generate power even after the sun goes down.
Most homeowners save around $60,000 over 25 years
- Vetted installers
- Unbiased advice
- Completely free
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