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Written byTamara Jude+1 otherReviewed bySarah WilderUpdated 03/25/2024
Tamara Jude
Tamara Jude is a seasoned content writer with more than seven years of experience in research and content production. She specializes in the solar energy, home warranty, and windows categories. Her interest in home improvement began as a child, when she regularly completed home projects alongsid…
See full bioSarah Wilder
Sarah Wilder is a solar workforce program analyst supporting the U.S. Department of Energy Solar Energy Technologies Office. Sarah has held various roles within the solar industry, including more than 10 years of photovoltaic (PV) design and installation work, four years as co-owner of a solar i…
See full bioChoosing the best solar panels for a home can feel overwhelming, especially if you are new to this technology. Solar panels are a big investment, and your choice will affect not only the aesthetics of your home but also the power and financial savings provided by your new system.
Our team has spent more than 300 hours researching the solar industry. In this guide, we’ll cut through the jargon to explain how different types of solar panels work. We’ll cover variations in design, materials, efficiency ratings, and more so that you can make an informed, confident decision for your home.
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Solar Panel Basics
Committing to going solar can be easy, but navigating the installation process may feel overwhelming. Doing some research can help you better understand solar technology and decide what system to install.
Solar panels are made up of dozens of photovoltaic cells (also called PV cells) that absorb the sun’s energy and convert it into direct current (DC) electricity. Most home solar systems include an inverter, which changes the DC electricity to alternating current (AC) electricity—the kind needed to power your home. Solar batteries can store unused energy for use at night or during an outage. You’ll want one of the best solar batteries to feel secure during outages or if you want to go off-grid.
There are three main types of solar panels: monocrystalline, polycrystalline, and thin-film. Monocrystalline and polycrystalline panels are used for residential installations, while thin-film panels are more common for small solar projects, such as powering an RV or shed.
Monocrystalline Solar Panels
Monocrystalline solar panels—or mono panels—are made from a single crystal. These are the best and most common type of solar panels for residential systems because they’re the most efficient solar panels and better suited for roofs with limited space. Their higher efficiency is perfect for homes with greater than average energy needs. Monocrystalline solar panels have a lifespan of 25+ years.
There are two kinds of monocrystalline panels:
- Passivated emitter and rear contact (PERC) panels: PERC panels are most commonly used for rooftop installations. They have an extra conductive layer on the backside of their PV cells to increase energy absorption.
- Bifacial panels: Bifacial panels can absorb light on both faces and at a higher rate than PERC panels. They are typically reserved for ground-mounted systems that leave both sides of the panels exposed. Bifacial panels are also used on awnings, canopies, and highly reflective white commercial roofs.
Design
Materials
Monocrystalline panels are mostly solid black but have some white space throughout. The black design makes them less noticeable on a rooftop.
Monocrystalline solar cells are manufactured using the Czochralski method, in which a seed crystal of silicon is placed into a molten vat of pure silicon at a high temperature. That creates a single silicon crystal, or ingot, which is then divided into thinner wafers. Those wafers make up the solar panels.
Polycrystalline Solar Panels
Polycrystalline panels are made using earlier solar technology, so they’re more affordable than the newer monocrystalline variety. However, because the technology is older, polycrystalline panels are less efficient than their modern counterpart.
Design
Materials
Polycrystalline panels have a blue hue that’s somewhat marbled in appearance, so you may see some variation in color and consistency among panels. Homeowners who don’t want to distract from their curb appeal should opt for monocrystalline over polycrystalline panels.
Polycrystalline panels use silicon solar cells, the same as monocrystalline panels. The difference lies in the cooling process for polycrystalline panels, which creates multiple crystals rather than just one.
Thin-Film Solar Panels
Thin-film solar cells are less efficient than monocrystalline and polycrystalline varieties. As a result of their lower efficiency, they are more often used in large industrial solar installations in which space is not a constraint. Thin-film panels can also be a good option for small solar projects, such as powering a boat, and small commercial buildings with thin metal roofs, such as a warehouse. Thin-Film panels also have a shorter lifespan compared to crystalline panels.
Thin-film panels have the sleekest appearance among the three panel types. They’re completely black, flat, and flexible in shape and size. They blend in easily on roofs, and they don’t require the scaffolding that monocrystalline and polycrystalline panels often do.
However, thin-film panels are not very efficient. You’d need many more—perhaps even enough to cover your entire rooftop—to generate enough power for a home. That means a higher overall cost and more opportunities for panel issues, failures, and degradation over time Because of all this, thin-film panels are almost never used for residential installations.
Thin-film panels are created by placing a thin layer of non-crystalline silicon, such as copper indium gallium selenide (CIGS) or cadmium telluride (CdTe), onto a solid surface, often glass. The photovoltaic substance used in the manufacturing process determines the properties of the final product, with amorphous silicon (a-Si) panels being the most flexible.
Compare the Major Types of Solar Panels
Type of Solar Panel | Pros | Cons |
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Monocrystalline |
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Polycrystalline |
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Thin-film |
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How Solar Panels Work
If you’re looking for more information about how solar panels work, the video below describes the process of how solar panels convert sunlight into electricity to power your home.
Solar Panel Costs
Monocrystalline panels are more costly to produce because they use a single silicon crystal, whereas polycrystalline panels can be made using leftover crystal fragments. Since production costs are lower and the manufacturing process is simpler, polycrystalline panels are much less expensive than monocrystalline panels. The cheapest type of solar panel is thin-film because of its ultra-light and thin construction.
Here’s the average price per watt for each panel type, which can give you an idea of how much solar panels will cost you. Note that you’ll need more polycrystalline panels than monocrystalline panels to power your home, and that thin-film panels should be reserved for nonresidential projects.
Average Cost Per Watt*
- Thin-film: $0.50–$1
Polycrystalline: $0.60–$1
- Monocrystalline: $0.60–$1.20
*Prices sourced from Fixr‘s contractor estimates.
Solar Panel Efficiency
The more electricity a solar panel can generate, the higher its efficiency rating. High-efficiency panels can generate more electricity while taking up less space, meaning you’ll need fewer panels for yourhome solar system. That’s why 35% of homeowners in our survey ranked efficiency as their No. 1 priority when shopping for solar panels.
Changes in sunlight throughout the day can impact your panels’ efficiency, since overcast skies will obviously reduce the amount of solar energy panels can absorb. High temperatures can also negatively affect energy efficiency. Panels build up heat throughout the day, lowering the power output by up to 30% during hot summer days.
Both monocrystalline and polycrystalline panels are suitable for most locations that receive an average amount of sunlight and have seasonal temperature fluctuations. Thin-film panels have a lower temperature coefficient than the other two panel types, meaning they lose less power as the temperature rises. This makes thin-film panels a good option for hotter climates or areas that get more annual sunlight.
While temperature changes affect all types of panels, those with high efficiency ratings account for these fluctuations and compensate for them in terms of overall power output. Monocrystalline solar panels have the highest efficiency ratings.
Below is a breakdown of efficiency ratings and power capacity for each solar panel type.
Monocrystalline
Polycrystalline
Thin-Film
- Efficiency: Over 20%
- Power capacity:300 watts and up
- Efficiency: 15%–17%
- Power capacity: 240–300 watts
- Efficiency: 6%–15%
- Power capacity: No standard measure, since thin-film panels aren’t uniform in size, but generally less output than crystalline panels
Other Factors To Consider When Selecting a Panel Type
Beyond sunlight exposure and heat, the following factors can impact a solar panel’s performance and longevity.
Solar panels are tested for hail impacts by dropping small steel spheres from a certain height or firing ice balls directly on panels to simulate hail.
Monocrystalline and polycrystalline panels are made of thicker materials and can therefore withstand hail hitting at speeds of up to 50 miles per hour. Thin-film solar panels are less resistant to hail because they’re more lightweight and flexible.
TheU.S. Department of Energy maintains a list of recommended specifications for solar panels in terms of their ability to withstand major storms, such as hurricanes. Panels that meet these specifications are designed with a locking or fastening mechanism to help prevent them from becoming windborne. Monocrystalline and polycrystalline panels are heavier and easier to modify with fastening devices than thin-film panels.
Our Conclusion
Monocrystalline solar panels are the best option for residential solar panel systems. Though more expensive than polycrystalline panels, monocrystalline panels perform better and last longer. This means that despite the higher cost, the increased efficiency and power output of mono panels may actually save you more money on electricity bills over time. Despite this, the majority of our survey takers chose polycrystalline panels—48% in fact. Roughly 29% chose monocrystalline panels, and 18% purchased thin-film. This is likely due to prioritizing upfront costs over long-term return on investment.
Polycrystalline panels are still a practical option for those who want to switch to renewable energy but can’t afford monocrystalline panels. Keep in mind that if you are worried about aesthetics, polycrystalline panels are the most noticeable of the rooftop solar options. There are also less common rooftop solar options that you may want to consider, such as solar shingles.
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We don’t recommend using thin-film panels for your residential solar system due to their low efficiency. However, they may be a good, affordable option if you want to power a shed, workshop, boat, or recreational vehicle.
Most solar panel installation companies will recommend a panel type and brand based on your home’s needs and your budget. Learn more about the solar panel companies we recommend in our guide.
FAQ About Residential Solar Power
How many solar panels are needed to run a house?
Most houses need about 30 solar panels. That estimate is based on an average energy consumption of 1,000 kilowatts per hour with 320-watt panels installed. The exact number of panels you need depends on several factors, including your average monthly energy consumption, your home’s size and available roof space, and your local climate and average sunlight.
Is it possible to run a house completely on solar power?
Yes, you can run a house completely on solar power. However, you’ll need backup generators and solar batteries that store excess energy to go completely off-grid. Off-grid systems are also larger and, thus, significantly more expensive than those tied to the power grid.
How long do monocrystalline solar panels last?
Monocrystalline solar panels can theoretically last 50 years, but they’re typically only covered under warranty for 25–30 years. All types of solar panels lose about 0.5% of their efficiency per year due to normal wear and tear, so they won’t be as effective in later years as when they were first installed.
What are the main disadvantages to solar energy?
The main disadvantage of solar energy is that solar panels are expensive to install, with an average cost of roughly $20,000. However, solar incentives, rebates, and tax credits can significantly reduce this price, and the annual savings you’ll receive on electricity bills will eventually pay for the system and then some.
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