What Are Solar Panels?

Solar panels work by converting sunlight into electricity, giving you a clean and renewable way to power your home. Solar panels help lower power bills, reduce your reliance on the electricity grid, and shrink your carbon footprint. Whether you’re curious about how solar panels work, their benefits, or whether installing a system is a good idea, this guide covers everything you need to know about residential solar panels.

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How Solar Panels Work

Solar panels work by converting sunlight into usable electricity through a process known as the photovoltaic effect. Each panel contains multiple solar cells, typically composed of silicon, a semiconductor material. When sunlight hits these cells, it excites the electrons, generating direct current (DC) electricity.

This electricity then passes through a piece of equipment called an inverter, which converts the DC electricity into alternating current (AC) electricity, which is used to power appliances in your home. The AC power is then distributed throughout the home for immediate use. If your system produces more electricity than you need, you can either store the excess energy in a battery for later use or send it back to the electric grid, depending on your system setup.

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Types of Solar Power Systems

Solar power companies can install different system types depending on a homeowner’s dependence on a utility company. Homeowners can choose the type of solar power system or solar array they would prefer based on their budget and needs. These systems include:

• Grid-tied: Grid-tied systems are the most cost-effective option. Your house remains connected to the utility company’s grid, and you can store any excess energy in their system for later use or net metering, which is a way the electricity company credits your account.
• Hybrid: Hybrid systems allow you to remain off-grid, but they have battery storage that serves as a backup in the event of a power outage. 
• Off-grid: This means the energy system is entirely self-reliant and doesn’t have access to the utility grid. Homes using this system have a backup generator during a power outage.

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Types of Solar Panels

There are four solar panel types on the market. The type of solar panels you choose depends on your budget, location, available space, and energy needs. Different solar panels also come in various sizes and shapes. Below is an overview of the options available:

Monocrystalline Solar Panels

Monocrystalline panels are also called single-crystal panels because they are made from a single, pure silicon crystal that’s split into different wafers. They’re the most popular panels because of their efficiency, longevity, and aesthetic. 

Monocrystalline panels have the longest life span of all four panel types, lasting about 25 years, and their efficiency rates are between 15% and 24%. They also offer a sleek black design. These panels are the most expensive because they use a lot of silicon, but their electricity output offsets the price tag. 

Polycrystalline Solar Panels

Polycrystalline solar panels are composed of silicon fragments, which makes them easier to build. A manufacturer melts the silicon fragments and pours them into molds, where they solidify. Although they’re less efficient than monocrystalline panels, with an efficiency rate between 13% and 16%, they’re more affordable. You can also install more of them if you have enough space, which makes up for their lower efficiency. 

Polycrystalline panels aren’t recommended for homes in hot climates, as both efficiency and panel lifespan decrease in high temperatures. They’re also more noticeable on a rooftop because of their bright blue color.

Passivated Emitter and Rear Contact (PERC) Panels

PERC panels are a newer panel type. They’re similar to monocrystalline and polycrystalline panels, but they have an extra layer underneath the cells. This additional layer is reflective and can send the light that passes through the panel back into the cell, creating more energy. That same reflective surface also prevents longer wavelengths from otherwise damaging the panel’s performance. 

PERC panels collect more solar energy than traditional panels by up to 12%. They’re more efficient, making them ideal for smaller spaces, and they’re only slightly more expensive.

Thin-Film Solar Panels

Thin-film solar panels are made of thin layers of different semiconductor materials. These panels use fewer materials than traditional silicon panels, but they’re also less efficient. At the same time, they are more affordable than traditional panels because they’re lightweight and flexible. 

The different materials you might find in thin-film solar panels include:

• Amorphous silicon (a-Si): Amorphous silicon is a very flexible material, so these panels aren’t susceptible to cracks the way others are.
• Cadmium telluride (CdTe): Cadmium telluride creates more energy and has a lower carbon footprint than other materials, but manufacturers can’t mass produce panels with CdTe because telluride is rare. Another disadvantage of CdTe-based panels is that they use cadmium, which is highly toxic.
• Copper indium gallium selenide (CIGS): The combination of copper, indium, gallium, and selenium makes this panel the most efficient thin-film type, but it still produces less energy than its silicon counterparts.
• Organic photovoltaic (OPV): These affordable OPV cells create electricity using organic polymers and molecules. They aren’t efficient and degrade quickly, but they’re popular in the building-integrated photovoltaic market, which replaces conventional building components with solar energy materials.

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Concentrating Solar-Thermal Power (CSP) Systems

Conventional methods to generate electricity use fossil fuels to create heat and steam. The steam this creates powers a turbine, which produces electricity. Fossil fuels account for 74% of greenhouse gas emissions, a leading factor in climate change, according to the U.S. Energy Information Administration (EIA).

To reduce the dependency on fossil fuels to produce energy, concentrating solar-thermal power (CSP) systems use mirrors to reflect sunlight onto a receiver filled with water. The sunlight heats the water, which powers the turbine and generates electricity with solar energy.

CSP systems are different from photovoltaic (PV) panels, which convert thermal energy into electricity. While CSP technology uses the sun’s energy to power a system, PV panels convert sunlight directly to electricity. CSP can power large-scale systems, such as power plants, but you wouldn’t use it to power individual homes like you would with PV panels.

PV panels aren’t just for individual home use, though. Solar farms have large collections of panels installed on acres of land to serve many homes and businesses.

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Solar Panel Benefits and Limitations

When homeowners invest in solar panels, they reap many benefits, but they also encounter some limitations. In this section, we’ll cover solar panel advantages and downsides, providing you with a comparison to help you decide whether this electrical power system is right for you.

The benefits of solar panels include:

• Energy independence: You’ll no longer need to rely on the utility company to power your home. By using solar batteries to store extra energy or choosing an off-grid system with a generator, you may not need to depend on an external power source and can keep your lights on when the power goes out in your neighborhood.
• Flexible energy options: You don’t need to own a home to go solar. By joining a community solar program, you can share an array with others and power your apartment or rental with shared solar energy.
• Net metering: The utility company may pay you for unused energy if you’re on a grid-tied system. When your solar power system is connected to the electricity grid, any unused energy returns to the utility company, which credits your account through net metering. 
• Sustainability: You lower your carbon footprint. Most homes rely on fossil fuels for power, but homes dependent on solar energy don’t contribute to greenhouse gas emissions as much as their conventional counterparts.
• Tax incentives: You can receive tax credits and incentives when you opt to go solar.
• Utility savings: Your electricity bill will be lower. However, your exact savings will depend on the cost of electricity in your location and your usage.

Despite the advantages that come with solar panels, you’ll find some limitations. The disadvantages of going solar include:

• Accessibility: Solar companies may not service your area, so it may be hard to find a service carrier depending on where you live.
• Not easy to move: Moving solar panels to your new home is difficult and expensive, so if you have them installed and decide to move, you may have to leave them with the new owners.
• Payback period: Solar panels are long-term investments, and it may take 10 years before your savings offset the installation costs, which is known as the solar payback period. 
• Reliability: Solar panels are weather-dependent and require a few hours of sunlight per day. If you live in a cloudy area or your home receives a lot of shade, your panels won’t be as efficient. 
• Size: Your home’s size factors into overall savings. Smaller homes may not have enough room to attach the panels to their roofs, and sometimes larger homes use too much energy to make solar panels a worthwhile investment.
• Upfront costs: Solar panel costs are high, and it could take a long time to see any savings. You may also need to purchase solar batteries for nighttime use, which can be expensive.

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Cost of Installing Solar Panels

The average cost of a 6–8 kilowatt (kW) solar system is approximately $19,619, based on responses to our 2025 survey of 1,000 solar customers nationwide. However, that average doesn’t consider incentives, such as the federal solar tax credit, which can lower costs. However, the cost of a residential solar panel system varies based on factors such as your home’s size, panel type, and installation specifics. The following factors can impact your total system installation cost:

• Location: States with favorable solar incentives and optimal weather conditions can offer better savings.
• Panel type: High-efficiency panels, such as monocrystalline and PERC panels, typically cost more than thin-film alternatives.​
• Roof characteristics: Complex roof designs or less common materials may increase installation complexity and costs.​
• System size: Larger systems generate more energy but incur higher upfront costs.​
• System type: Off-grid systems cost more than grid-tied setups since they require additional components like batteries and generators.

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Solar Panel Lifespan

A solar panel’s lifespan is typically 25–30 years. While solar panels can often continue generating electricity beyond that timeframe, their efficiency gradually declines over time. On average, solar panels degrade at a rate of around 0.50%–0.80% per year, meaning you can expect a slow but steady drop in output over their lifespan. Environmental factors like wind, debris, snow, and extreme temperatures can accelerate this wear.

Homeowners can generally count on their panels to perform reliably for the length of any included warranties, which typically covers both manufacturing defects and expected performance. Many manufacturers offer a performance warranty guaranteeing 80% or more of the panel’s original output after 25 years, along with a product warranty that covers material or workmanship issues.

To extend the life of your solar system, consider the following tips:

• Choose a reputable installer: Research companies through customer reviews and Better Business Bureau (BBB) ratings to ensure quality workmanship.
• Schedule regular inspections: Complete solar panel maintenance and inspections twice a year to catch potential issues early.
• Protect your panels: Install wire mesh, critter guards, or other protective gear to shield panels from animals, debris, and harsh weather.
• Invest in high-efficiency panels: Monocrystalline and passivated emitter and rear contact (PERC) panels tend to degrade more slowly and perform better over time.

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Our Conclusion

Solar panels give you a sustainable way to power your home, reducing your reliance on the grid and lowering your energy bills. By harnessing sunlight, you can generate clean electricity, increase your home’s value, and shrink your carbon footprint. With improving technology and available incentives, going solar is more practical than ever, helping you save money while gaining more energy independence. Working with a top solar provider enables you to get the right system for your home

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FAQs About Solar Panels

Are solar panels always live?

Yes, solar panels are always live. They will always be on, but they may not generate electricity when they aren’t exposed to sunlight.

How long can a house run on solar power alone?

A house can run on solar power alone for 24 to 48 hours if you are using only basic utilities and have a solar battery. Running an air conditioner or the heat will drain the energy faster.

Can hail damage solar panels?

Yes, hail can damage solar panels. Light hail won’t destroy the panels, but a severe hailstorm can cause significant damage. You can protect your solar panels from hail using mesh wire, coverings, or spray-on monomers. A solar panel installer can also adjust the angle of the solar panels to protect them.

Do you have to clean solar panels?

You may have to clean solar panels of dirt and debris that can obstruct the sun’s rays and make the panels less efficient. However, regular cleaning is often unnecessary because rain is typically enough to keep your solar panels clean. 

Can you walk on solar panels?

You shouldn’t walk on solar panels because they could break or your weight can reduce their efficiency.