Solar technology harnesses the sun’s energy to generate electricity. It’s a form of clean energy that powers your home through solar panels on your roof. But what are solar panels and how do solar panels work? In this article, we’ll explain how solar panels power a home, the different panel types, and the benefits and drawbacks of solar.

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Types of Solar Power Systems

Solar power companies can install different system types according to how dependent a homeowner wants to be 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-tie: Grid-tie 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 completely self-reliant and doesn’t have access to the utility grid. Homes using this system have a backup generator in the event of a power outage.

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Types of Solar Panels

There are four solar panel types on the market. The type of panel you choose depends on your budget, location, available space, and energy needs. Different solar panels also come in various shapes and sizes. 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 design in black. These panels are the most expensive out of all four panel types 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. The use of fossil fuels accounts for 75% of greenhouse gas emissions, a leading factor of climate change.

To reduce the dependency on fossil fuels to produce energy, 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.
• Home value: Your home’s value increases. Buyers are willing to pay about $15,000 more when a seller has upgraded their power system with solar cells.
• Net metering: The utility company may pay you for unused energy if you’re on a grid-tie 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 receive a tax credit when you opt to go solar. The U.S. Department of Energy offers credits if you install solar panels on your house, which covers 30% of installation costs.
• Utility savings: Your electricity bill will be lower. According to Energysage.com, homeowners save an average of $20,000–$96,000 over 25 years; your exact savings will depend on how much electricity costs 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. 
• 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 panels cost a lot of money to install, and it could take a long time before you start 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 cost of solar panels depends on your home’s size, panel type, and a few other factors, but on average, homeowners spend $31,460 for a 11-kilowatt (kW) residential solar panel system, or $22,022 after applying the federal solar tax credit. Solar panel installations of this size can cost between $25,960 to $36,960 before applying the federal solar tax credit.

The following factors will affect your solar panel’s price tag:

• Location: Some locations have better tax incentives and savings plans because they have more ideal weather conditions for solar energy production. Certain states also offer robust incentive plans.
• Panel type: Monocrystalline and PERC panels are more expensive than thin-film panels.
• Roof angle and type: Solar panels need to sit at a certain angle. The solar installation company may need to adjust or add material to the panels depending on your roof’s incline or type, such as shingles or wood shakes. This could result in a higher price tag.
• Size: The solar energy system’s size affects the cost. 
• System type: Choosing an off-grid system will cost more than a grid-tied system.

Cost data in this section was sourced from EnergySage.

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Solar Panel Lifespan

According to industry standards, a solar panel’s lifespan is 25–30 years. It will continue to work after that time frame, but its output and efficiency will decrease from the manufacturer’s initial projection.

Solar panel degradation rate is up to 0.8% annually. This means a panel’s output slightly diminishes each year. The panels degrade faster if other external factors, such as wind and debris, affect them. 

Homeowners can assume their panels will work for the length of the warranty, which may cover manufacturer defects and projected energy production. You can make your PV panels last longer by:

• Hiring a reputable installer: Read reviews and Better Business Bureau ratings to learn about an installer’s experience and reputation.
• Inspecting your panels often: Inspect and maintain panels twice per year to extend their life span.
• Protecting panels from damage: Install wire mesh, critter guards, and other devices to protect the panels against inclement weather and animals.
• Using high-quality panels: Select PERC or monocrystalline panels to extend your system’s life.

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Our Conclusion

Oil is currently the main source of energy production in the United States, but supplies are shrinking. Finding and using alternative power sources will increase energy stores without the use of fossil fuels. Renewable energy sources, such as solar technology, can help lift the burden on oil reserves and help the planet. We recommend you install solar panels if your power usage is high and you plan on staying in your home for a long time.

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FAQ 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. 

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