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A solar system can provide electricity for over two decades, saving homeowners thousands of dollars in power bills over time. Getting familiarized with the main types of solar panels is a useful first step when deciding on a solar panel system. This way, you can pick the best option for your home or business.

No matter which type of solar panel you choose for your project, make sure it's a high-quality product with a solid manufacturer warranty. Getting a professional installation is also critical, since even the best solar panels can malfunction when wired incorrectly. Poor workmanship can also create a fire risk, and the warranty will be voided if solar panels are not used as indicated by the manufacturer.

If you're ready to get a quote for a home solar installation, you can use this tool or fill out the free form below to get connected to a certified professional in your area.

3 Main Types of Solar Panels

You will find that solar panels come in many sizes, ranging from large commercial modules that are nearly 7 feet tall to compact and portable panels that fit in your pocket. However, the vast majority can be classified into three main types: monocrystalline, polycrystalline and thin-film. Each uses materials that produce electric power when they receive sunlight, but the specific materials used in the panels are different.

Like in any design decision, each type of solar panel has pros and cons, which are summarized below:

Type of Solar Panel

Major Pros

Major Cons


+ Highest efficiency, which means more kilowatt-hours per square foot covered

+ Long lifespan (25 years or more)

- Most expensive type of solar panel


+ Balanced cost and efficiency: intermediate between monocrystalline and thin-film solar panels

+ Long lifespan (25 years or more)

- Lower efficiency than mono panels

- High temperatures can lower their productivity and durability


+ High temperatures only have a small impact on their productivity

+ Lower weight than mono and poly solar panels

+ Lowest cost per panel

+ There are flexible and adhesive thin-film panels available

- Lowest efficiency, which means fewer kilowatt-hours per square foot covered

- Generally less durable than mono and poly solar panels

Polycrystalline and monocrystalline panels both use solar cells made of silicon crystals, but with a different physical structure. On the other hand, thin-film solar panels use non-crystalline silicon or other photovoltaic materials.

Monocrystalline Solar Panels

Monocrystalline solar panels have the highest efficiency ratings in the industry. These solar panels can normally convert over 20% of sunlight into electricity, and the most efficient panels now exceed 22% efficiency. Mono panels are an excellent choice when you have limited roof space, since they will generate more electricity per square foot.

Mono solar panels are also characterized by their black photovoltaic cells, and many homeowners prefer this appearance over the lighter blue tone of poly solar panels. The main downside of these panels is their high cost, but in return, they give you more electricity per panel you purchase.

Polycrystalline Solar Panels

Polycrystalline solar panels have a lower efficiency than monocrystalline silicon panels — typically below 17% — but they are also more affordable. High efficiency really only becomes critical when your roof has limited space for solar panels and you need to make the most of the available area. When space is not a limitation, you can simply install a few additional polycrystalline panels to compensate for their lower efficiency.

Contrary to popular belief, lower efficiency does not mean lower quality when comparing solar panels. In the case of polycrystalline panels, this is just a consequence of their material property: They have multiple silicon crystals per cell, as opposed to a single crystal that carries electrons more efficiently. You can find high-quality solar panels of both types, mono and poly, with solid warranties from their manufacturers.

Thin-Film Solar Panels

Thin-film solar panels are not divided into cells like polycrystalline and monocrystalline modules. Instead, their entire surface has layers of photovoltaic material. Since these panels use material layers instead of rigid cells, they can be manufactured to be flexible and lightweight. There are also adhesive thin-film panels, which can be used on windows and other vertical surfaces. These panels are also popular for RV solar energy systems.

However, thin-film panels generally have a lower efficiency than the other two types, which means you need to cover a larger area to produce as much power as mono and poly panels. For this reason, thin-film panels are more suitable for large commercial and industrial rooftops, or ground-mounted solar farms. They are not normally recommended for homes, since they need too much space to be productive.

Key Differences: Design, Cost & Efficiency

When comparing solar panels, the purchase decision is often based on appearance, cost and efficiency. While all types of solar panels perform the same function, there are important differences between them in these three areas:

How Different Types of Solar Panels Look

The appearance of solar panels can be described based on their color and number of cells.

  • Monocrystalline solar panels have black cells with cropped corners, and most panels have 60 or 72 silicon solar cells. The latest designs use 120 or 144 half-cells that boost efficiency, but panel dimensions are roughly the same.
  • Polycrystalline solar panels have blue cells with sharp corners. Like mono panels, they are normally available with 60 or 72 cells (or 120 or 144 half-cells in newer models).
  • Thin-film solar panels have a uniform surface with layers of photovoltaic material, instead of separate solar cells. Their color depends on the material composition, and you can find black, blue or even gray thin-film panels.

Cost of Each Solar Panel Type

The specific price of a home solar system will depend on the panel brand and model, as well as local labor costs. Also keep in mind that your total installed cost of solar will include components like the inverter, racking, wiring and circuit breakers. However, the cost of solar panels themselves can be ranked as follows:

  • Monocrystalline: Highest price
  • Polycrystalline: Intermediate price
  • Thin-film: Lowest price

This is the general pricing trend you can expect, but there may be exceptions.

Efficiency and Power Ratings

The efficiency and power output of solar panels is closely related, since a higher efficiency means more watts with the available sunshine. However, you also need to consider the dimensions of solar panels, since a larger product has more area to collect sunlight.

Assuming you compare solar panels of similar sizes, you can expect the following ranking when it comes to efficiency and wattage:

  • Monocrystalline: Top efficiency, typically over 19%
  • Polycrystalline: Medium efficiency, typically 15-17%
  • Thin-film: Lowest efficiency, typically below 15%

Solar manufacturers are constantly investing in research, and all three types of solar panels have been improving over time thanks to new technology. There are now thin-film panels that can match the efficiency of mono and poly panels in laboratory conditions. However, they are not widely available as commercial products yet.

What Are The Different Types of Solar Panels Made Of?

The appearance and efficiency rating of solar panels depends on their material composition. While having high efficiency is favorable, this metric is overestimated in some cases. There are high-quality solar panels of all three types, and you can get excellent results with polycrystalline and thin-film panels when space is abundant.

As mentioned above, polycrystalline and monocrystalline panels are both made of crystalline silicon wafers. However, the microscopic structure of those crystals is different in each type of panel:

  • Monocrystalline solar cells are made from PV cells that are cut from a single crystal of pure silicon (hence the prefix "mono"). This is an advanced manufacturing process, which is a key reason why mono solar panels have higher prices.
  • Polycrystalline solar cells are made from multiple crystalline silicon fragments that are melted together during the manufacturing process, and they are also called multicrystalline for this reason. Their manufacturing process is simpler, since there is no need to carefully grow a single crystal of silicon. This leads to a lower cost, but also a lower efficiency.
  • Thin-film solar panels don't use silicon crystal cells. Instead, they use thin layers of photovoltaic material. The most common chemical compositions are copper indium gallium selenide (CIGS), cadmium telluride (CdTe) and amorphous silicon (a-Si).

Choosing the Right Panel for Your Solar Installation

Monocrystalline solar panels are often considered the "best" due to their superior efficiency, but any of the three types of solar panels can achieve great performance when used in the right applications. Efficiency is only one of several performance metrics, and there are cases where polycrystalline panels offer a better return per dollar invested. Thin-film panels may not have the best efficiency, but their low weight and reduced thickness make them viable in applications where the other types are impractical.

If you're a homeowner who wants to maximize electricity production with limited roof space, monocrystalline panels are the recommended option. The same applies if you have plenty of space but want your solar panel system to be as compact as possible. Finally, mono panels are recommended if you prefer the black color of their solar cells.

When space is not a limitation for your home solar system, you can also consider polycrystalline solar panels. They are also recommended when you want to keep the budget as low as possible: Assuming equally sized systems with the same number of panels, the total cost will be less with polycrystalline options.

Thin-film solar panels are not generally recommended for residential roofs. Since their efficiency is low, you need to cover a much larger area with more panels to achieve a significant output. However, thin-film panels are excellent for recreational vehicles and camping, as they are lighter and more portable. You can also find thin-film solar panels with flexible or adhesive designs, which can be used in surfaces that are not suitable for the other two types.

So, which type of solar panel is best for your home? To find out for sure, you'll need to talk to a solar installer near you. Most of the best solar companies offer free consultations that can tell homeowners what type of panels they should buy and how much they will cost.

To get started, you can use this tool or fill out the form below and get connected to a pre-screened solar installer in your area.

Leonardo David is an electromechanical engineer, MBA, energy consultant and technical writer. His energy-efficiency and solar consulting experience covers sectors including banking, textile manufacturing, plastics processing, pharmaceutics, education, food processing, fast food, real estate and retail. He has also been writing articles about energy and engineering topics since 2015.
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We Are / DigitalVision / Getty Images

Humanity's digital presence is growing – and with it, our carbon footprint.

In May of 2020, one-third of employed people were conducting their jobs remotely as a result of the coronavirus, up from a mere 6%. While taking our work (and many other aspects of our lives) online seems more sustainable – as our need to travel diminishes and hard copies become all but obsolete – it intensifies our digital carbon footprint, and carries a huge environmental cost.

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Average Cost of Solar Panels in Arizona: What to Expect (2022)

We break down what the average homeowner pays for solar in Arizona.

Frank Staub / Photodisc / Getty Images

Anyone who has spent time in the southwestern U.S., particularly in the deserts of Arizona, would find it no surprise that the region has some of the best natural solar resources in the country. But all the sunshine in the world won't mean anything if the cost of solar panels in Arizona keeps renewable energy out of reach for homeowners across the Grand Canyon State.

From reduced energy bills to shrunken carbon footprints, there are many benefits of going solar. Regardless, for most homeowners, making the switch comes down to one key question: How much do solar panels cost in Arizona?

In this article, we'll discuss the average cost of solar panels in Arizona as well as key information about financing solar, public policies that may incentivize solar installations and more. If you want to see how much solar would cost for your home, specifically, you'll need to get a free quote from a solar installer near you. You can do so using this tool or by filling out the form below.

How Much Do Solar Panels Cost in Arizona?

Solar panel costs in Arizona are about on par with the U.S average. Local factors and supply limitations don't hamper Arizona installations or pull prices in either direction. Based on market-based research and data from top solar companies, we've found that the average cost of solar panels in Arizona is $2.61 per watt (the national average is $2.66 per watt).

Of course, solar systems aren't purchased one watt at a time, so what does that price look like in terms of actual installations? Using the state average, for a modestly sized 5-kilowatt (kW) system, the total system cost would be $13,050, but after the federal tax credit is applied, out-of-pocket costs would be lowered to about $9,657.

For larger systems to be installed on homes, businesses, schools or other facilities, average solar power costs break down as follows:

Size of Solar Panel System Arizona Solar Panel Cost Cost After
Federal Tax Credit
5kW $13,050 $9,657
6kW $15,660 $11,588
7kW $18,270 $13,520
8kW $20,880 $15,451
9kW $23,490 $17,383
10kW $26,100 $19,314

The above table provides statewide average prices, but each home solar panel installation will have its own unique characteristics, so costs will vary in actuality.

Some installations will be more straightforward (such as those on a roof that readily faces the sun) while others will be more complicated (such as an irregular-shaped roof or a ground-mounted system), so the actual price for a specific project is best estimated with an installer who can account for your individual needs.

What Determines the Cost of Solar Panels in Arizona?

There are a number of factors that can influence the cost of solar panels in Arizona, including the extent of your home's energy needs and the local incentives you're eligible for. Here are a few other key things that will play into pricing:

Solar Equipment

Not all solar energy systems are alike, and the specific equipment chosen for your project will influence the final cost. Solar panels themselves are seeing lots of research and development, meaning the most efficient solar panels can generate greater amounts of electricity — but they come at a higher cost.

Similarly, things like inverters, solar batteries and the mounting equipment needed to secure the panels to your roof will vary in cost based on the quality of materials and complexity of the install. If you opt for added features like rotating panels or smart technology, your investment will be even more significant. These factors can all be discussed during a free consultation with a solar expert.

Solar Financing

Regardless of the size and quality of the solar system being installed, the total will usually be relatively high upfront. Because of these capital requirements, it's extremely common for customers to finance their solar systems. The type of financing used will not only impact what a customer pays upfront, but it will also affect the length of the customer's solar payback period, or how long it takes to "break even" on the investment.

Here's how the three most common payment options can affect the cost of solar panels in Arizona:

  • Cash: For homeowners with the capital available to cover the full price of their solar system, it's smart to pay in full upfront. This is less common because of the aforementioned high price point, but if workable, it results in the lowest overall cost and thus shortens your payback period.
  • Loans: If you're unable or unwilling to pay in full, there's the option to take out a simple loan to pay for the solar system. A solar loan can allow you to purchase a more expensive, premium system, but of course, loans come with interest, and that extra cost will eat into your payback period.
  • Leases or power purchase agreements (PPAs): Lastly, potential solar customers may opt to work with a solar company that leases panels to homeowners. With this payment method, you don't have to pay upfront costs, but you also don't own the system (and, thus, are ineligible to cash in on tax credits). In the long run, the amount you will save on energy bills will be much lower, but you are also relieved of the burden of paying for the system yourself.

Installation Company

A third factor that really impacts the cost of solar systems for Arizonans is the choice of installation company. The solar industry is booming, and as such, there is no shortage of contractors and installers who will be eager to help you install your residential solar system.

As with any major home improvement project, different installers have their own rates, oftentimes correlated with the quality or even speed of their work, and it's up to the customer to do their homework to evaluate potential installation companies. Simply going with the lowest-cost installation company may not be wise if it isn't reputable, but at the same time, certified local installers may charge lower prices to compete with big-name national installers.

Our best advice is to look at the best solar companies in Arizona, research what deals or specials are available, and talk to neighbors or look at online reviews to find a company that offers you a good price and will deliver the quality of work you need.

Arizona Solar Incentives

Public policy leaders have done a fair job of offering financial incentives that lower the cost of solar in Arizona. Although the state's net metering program was phased out in 2016, there are still a number of tax credits and incentives available to homeowners. These include:

Arizona Solar Incentive How it Affects the Cost of Solar Panels in Arizona
Arizona solar tax credit This statewide program allows people who install solar on their homes to be credited 25% of total installation costs (up to $1,000) in the form of a personal income tax reduction.
Solar tax exemptions The 5.6% of sales tax that's typically charged in Arizona is not applied to the purchase of solar equipment.
Similarly, most upgrades to homes will increase the value of the home, and that value is what is taxed via property taxes. Arizona, however, excludes the value increase from solar panels when evaluating how much property tax you must pay.
Local solar incentives On top of state incentives, numerous towns, cities and counties may have their own incentives to encourage citizens to engage with solar. Because these can vary greatly from one jurisdiction to the next, you should research your area (or call your local representatives) to find out more.
Federal solar tax credit Anyone in the U.S., including Arizona, is able to take advantage of the federal solar investment tax credit, or ITC. For any solar systems installed before the end of 2022, 26% of the cost of the system is available as an income tax credit.

FAQ: Cost of Solar Panels in Arizona

Is it worth going solar in Arizona?

Yes, it is generally worth going solar in Arizona. Solar panels are a great way to reduce electric bills and carbon emissions for your home or business. Depending on the size and cost of the system, customers who install solar can expect to see a full return on their investment decades before the end of life of the system, turning additional savings into pure profit.

How long does it take for solar panels to pay for themselves in Arizona?

The average payback period for solar panels is about eight years, and the average lifespan of a system is about 25 years. The payback period can be greater or shorter depending on the size of installation, tax incentives utilized and total cost paid by the customer.

How many solar panels are needed to power a house in Arizona?

The average home needs about 20 to 25 solar panels to offset 100% of energy needs. However, that figure will vary widely based on the energy used by the home, the size and efficiency of the panels, how much shade falls onto the panels from nearby buildings or trees, and other factors.

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What Is Solar Energy & How Does it Work?

We walk you through the basics of solar power.

Tim Robberts / Stone / Getty Images

For homeowners who are looking for clean energy solutions, solar power is utterly essential. But what is solar energy, exactly, and how does solar power work?

Solar energy is the energy emitted by the sun that reaches the earth's surface. In this article, we'll cover how it's converted into electricity that we use to power our lives, as well as discuss the biggest advantages and disadvantages of using solar energy.

The U.S. has one of the best climates for solar power in the world and is home to some of the best solar companies and manufacturers. So how should we take advantage of this natural, renewable energy we enjoy in such abundance? Let's dive in.

Solar Energy Definition

In its simplest form, solar energy is the heat and light released by the sun. Individual particles of sunlight are known as photons, and they carry high amounts of the sun's energy to Earth. In fact, during any given hour, the Earth receives enough solar energy to theoretically fuel our entire population's energy needs for one full year.

But where does all of this solar power actually come from? Well, like any other star, the sun is basically one big nuclear reactor. There are nuclear fusion reactions happening in the sun's core all the time, a process through which hydrogen atoms collide and fuse to create helium atoms.

This process produces an enormous amount of energy, as the sun fuses about 620 million metric tons of hydrogen every second.

Nuclear fusion is the process through which hydrogen atoms collide and fuse to create helium atoms.MARK GARLICK / Getty Images

That solar energy can be collected here on Earth via photovoltaic technology, which converts solar energy into electricity that can be used to supply power to a home or a business. Solar power currently represents 18% of the global energy economy, and it's rapidly gaining in popularity (and necessity), largely thanks to the falling costs of solar and a desire among governments and homeowners alike to reduce energy costs and carbon emissions.

Using Solar Power

You've likely heard the term "PV" associated with solar power, which as we've mentioned refers to photovoltaic technology used in most solar cells. Most commonly, PV cells are made with a silicon semiconductor due to its cost and abundance. Generally used for small-scale applications, such as residential solar systems or portable solar generators, PV represents the most common method of harnessing solar energy.

Another option, called solar thermal capture, is typically better suited to produce solar electricity on a larger scale, like in a power plant.

We'll focus more on the former, as it's the most common method.

Converting Solar Energy via Solar Panels

By installing solar energy systems made with solar photovoltaic cells, or PV cells, home and business owners can collect solar energy and convert it into electricity. Here's a breakdown of that process:

  1. The sun's photons reach the surface area of the solar panel, and through the photovoltaic effect, those photons excite and displace loose electrons within a solar cell.
  2. Solar panels are designed so that these displaced electrons flow toward metal plates that line the outside of the panel. This creates an energy current.
  3. This electric current within the solar panel is a direct current (DC), which has to be converted into an alternating current (AC) in order to be used as electricity for a home. Inverters convert the current from each panel.
  4. This AC electricity can then be channeled to the primary circuit board of your home, where it can be directed either into the home's electrical system as power or into a battery to be stored for later use. If your utility company has a net metering program, you can also send excess energy to your local power grid in exchange for energy credits.

Usable sunlight hits a solar cell, which sets off the photovoltaic effect.Alejomiranda / Getty Images

Solar PV is one of the best methods we have today for generating power on a large scale with a renewable, clean resource like solar energy.

Why Switch to Solar Energy?

The benefits of solar power go beyond just saving money on your energy bills; you can take complete control of your electricity use and energy efficiency, reducing or even eliminating your reliance on utility companies. Even more impactful, you can directly lower greenhouse gas emissions and your reliance on fossil fuels, which provides a number of tangible environmental benefits.

But are solar panels really worth it for homes and businesses? Let's walk through the pros and cons of solar energy.

Environmental Benefits of Solar Energy

The environmental benefits surrounding solar energy are perhaps the most well known:

  • Being a clean and renewable energy resource, collecting solar energy directly offsets carbon emissions and air pollution associated with burning fossil fuels like oil and gas.
  • Though not as well publicized, mining and burning coal, as well as fracking natural gas, require an extremely high volume of freshwater. Using solar energy rather than non-renewable resources contributes to healthier water systems by fighting water scarcity and acidification.
  • No matter which way you look at it, solar technology helps us reduce our reliance on fossil fuels and the companies that profit off of environmental degradation. Every single home that goes solar gives a small slice of power back to the people.

Financial Benefits of Solar Energy

There are also a number of financial perks that come with solar, including:

  • Solar energy use can reduce your monthly electric bills and, in some cases, eliminate those bills completely. This produces big cost savings over time.
  • When you buy solar panels, there are a number of tax credits, incentives and rebates available to offset startup costs, including some available at the federal level and some that are state-specific. More companies are adopting solar financing to increase accessibility.
  • Most residential and commercial solar systems will produce electricity for 20 to 30 years and require very little maintenance. This allows you to reliably budget your energy costs decades in advance rather than relying on power plants and public infrastructure, which is far less predictable.

Challenges of Solar Energy

Solar power is one of the best renewable energy sources available to us, but that doesn't mean it's perfect. Some of the most significant challenges to solar energy include:

  • The initial cost of solar panels is fairly significant, typically ranging between $10,000 and $20,000. Tax incentives and monthly utility savings can offset this cost, but paying these upfront costs just isn't an option for every homeowner.
  • Some homes aren't suited for solar. If your house is shaded by trees or other buildings, or you don't get enough exposure to the sun, then a home solar system may not work out.
  • If you live in an area where electricity is inexpensive, then the savings you get from a solar system may not be worth the cost and the hassle.
  • It's much better to deal with a broken solar panel than a leaky oil rig, but even solar panels have an impact. With well over a million panels in use nationwide, we'll have to address the system for recycling solar panels.

Is My Home Suitable for a Residential Solar Energy System?

The best way to determine whether your home is a good fit for solar electricity is to contact a solar installer in your area. A solar energy specialist can come to take a look at your home and give you a custom recommendation.

Generally speaking, solar energy is best suited for those who live in sunny areas, have plenty of surface area on a south- or west-facing roof and whose homes are unobstructed by trees or neighboring buildings.

What to Look for in a Solar Energy System

As you shop around for home solar systems, make sure to keep the following factors in mind (read our guide to purchasing solar panels for more information):

  • The efficiency of your solar panels, or how much sunlight they actually turn into electricity (the most efficient solar panels convert over 20%).
  • The capacity of your solar battery storage system.
  • Warranties and other protections for your home solar system.
  • The total number of panels you need to get the desired results.
  • The services offered by your solar installer (such as individual system design).

If you're interested in solar, it only takes 30 seconds to get a free, no-obligation quote. You could save up to $2,500 per year on utility bills and get a tax rebate all while reducing your carbon footprint. Use this tool or fill out the form below to get started.

FAQ: What is Solar Energy?

What is solar energy in simple words?

Solar energy, in simple words, is the light and heat radiated by the sun. Here on Earth, we can collect that solar energy with solar panels and convert it into electricity we can use to power our homes.

What are five advantages of solar energy?

Five advantages of solar energy include:

  1. It's a truly renewable energy source that directly offsets carbon emissions and air pollution.
  2. It helps homeowners save money on power bills.
  3. There are low maintenance costs for homeowners.
  4. Solar can be used in remote applications to power homes or shelters that aren't connected to an energy grid.
  5. Solar panel manufacturing and installation creates thousands of green jobs per year.

How do you explain solar energy to a child?

Here's how we would explain solar energy to a child: You know how when you step into the sun, you feel hot? That heat is a form of energy. Solar panels are a way of catching that energy, and using it to power your home.

Karsten Neumeister is a writer and renewable energy specialist with a background in writing and the humanities. Before joining EcoWatch, Karsten worked in the energy sector of New Orleans, focusing on renewable energy policy and technology. A lover of music and the outdoors, Karsten might be found rock climbing, canoeing or writing songs when away from the workplace.
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We're here to help. Below, you'll find nine of the most common arguments against solar. Of course, this goes beyond just speaking with family — we hear the following misconceptions about solar from a number of sources, so we've decided to put together a guide about how to address them.

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So, you've read up on the best solar panels available and have decided to prioritize efficiency. Smart move. Buying the most efficient solar panels provides you with the most bang for your buck when working with limited roof space and is often (but not always) the best choice for homeowners.

In its simplest terms, solar panel efficiency refers to the amount of sunlight that falls on the panels that is converted into energy, or solar power. In this article, we'll break down what makes solar efficiency important and help you pinpoint the most efficient solar panels for your home.

If you're ready to seek out a certified solar installer in your area, you can use this tool or fill out the form below to get connected and receive a free quote.

Understanding the Efficiency of Solar Panels

Efficiency measures the amount of electricity a solar panel produces relative to the amount of sunlight (or irradiation) that strikes its surface. The most efficient solar panels on the market today only reach about 22.8% (shoutout to SunPower) — meaning that the panel converts about 22.8% of the sun's irradiance into usable AC electricity.

This may sound like a small amount, but the rapid progress of solar technology has surpassed most expectations. Only about 10 years ago, solar panels averaged around 15% efficiency. The first solar panels from the mid-1950s only reached an efficiency of 2%. There are currently panels in development reaching efficiency levels nearing 50% that we may see hit the market sometime in the future.

Tracking Solar Panel EfficiencyData Credit: National Renewable Energy Laboratory (NREL)

What Are the Most Efficient Solar Panels Available Today?

With so many recent advancements in solar technology, let's take a look at the most efficient solar panels available in 2022. Based on our research, these are the best solar panels for efficiency at the time of publication:

Most Efficient Solar Panels

Efficiency Rating


SunPower Maxeon M-Series


420-435 W



405 W

Jinko Solar Tiger Neo


620 W

REC Solar Alpha


405 W

Panasonic EverVolt


380 W

Trina Solar Vertex S


670 W

Silfab 380-BLK


380 W

FuturaSun FU M Zebra


360 W

LONGi Solar Hi-MO 5


485-505 W

Q Cells Q.Peak DUO G9+


360 W

Power refers to the wattage output capacity of the panel. The more powerful the panel, the more electricity it is able to produce. Note that power works in conjunction with efficiency, rather than determining it.

What Determines Solar Panel Efficiency?

Two main factors determine solar panel efficiency: the makeup of the photovoltaic (PV) cell, and the structure of the panel. You might wonder what differentiates the two.

Solar Cell Efficiency

A solar cell is the smallest unit within a solar panel, usually composed of silicon atoms. The photovoltaic effect — which is the process by which sunlight is turned into electricity — happens in the solar cells themselves, and solar panels join together multiple cells to produce higher amounts of power and allow that power to flow through a home.

Solar cells on a solar panelvisdia / Getty Images

The most efficient types of solar panels are usually monocrystalline (rather than polycrystalline or thin-film). In this type of panel, the solar cell is cut from one solid silicon crystal. This leads to fewer imperfections in the cell, making them more capable of absorbing sunlight and, thus, more efficient.

It's possible you've heard about N-type or P-type solar cells in your research as well. This won't matter very much to the average customer, but if you're curious, these solar cell types differ in their chemistry due to the number of electrons they carry. N-type cells are negatively charged (via phosphorus), while P-type cells are positively charged (via boron). Multi-junction solar cells exist, too, made with both P- and N-type materials.

Solar Panel Efficiency

Overall solar panel efficiency has more to do with the structure of the panel itself. Even if you have the most efficient solar cells available, the next step is to gather those electrons and direct a current in a specific direction. A solar panel has to be as smoothly interconnected as possible, so as not to lose any energy in this part of the process. Temperature, cell type and design will have a large effect on overall efficiency in this context.

Why Is Solar Panel Efficiency Important?

It would be unfair to equate the most efficient solar panels with the best solar panels, as a number of other factors — namely durability, cost, warranty and power — can have a large impact on overall quality.

However, in residential solar, efficiency is typically one of the more important considerations. Here's why.

Quicker Payback Period

The more efficient your solar power system, the higher your power output will be, and the more quickly you'll recoup your initial investment. The cost of solar panels can be intimidating, but efficient panels will help slash a larger portion of your electricity bills, accelerating your solar payback period.

Something else to keep in mind is that the more efficient your solar panels are, the lower number of solar panels and inverters you'll need to achieve your home energy goals.

Better for Limited Space

Many residential solar energy projects are confined in terms of space available for solar panels. Some might see their roofs and think there's plenty of space, but zoning laws and regulations often require spaces between panels and gaps between the arrays and the sides of the roof. For homes with less roof space, high-efficiency panels allow you to do more with less.

In commercial solar installations where you have more space to work with, efficiency won't be as big a factor.

Doing More With Less

In addition to working with limited space, requiring fewer solar panels lowers the impact of your solar project itself. As Dr. Yifeng Chen, head of efficiency research and development at Trina Solar, says, "improving module efficiency is a key to helping customers save land, labor, cables, etc."

The highest-efficiency solar panels require fewer materials, shipping costs and waste. It may not seem like much to shave off one or two panels from your solar array, but seeing as the U.S. averages some 3 million solar installations per quarter, the impact can add up.

Other Factors Impacting Efficiency

At the risk of getting too technical, here are a number of other aspects of solar panels that factor into efficiency.


The spectrum of light that a solar cell is able to absorb can vary. Most modern solar cell technology is only capable of capturing visible light, excluding other wavelengths like infrared and UV rays. In general, the wider the spectrum of light that can be captured, the more efficient the cell will be. Some researchers are currently focusing on solar cells capable of capturing infrared rays, which would dramatically increase efficiency.


High temperatures and extreme weather conditions can put a lot of stress on a solar panel. In fact, solar panels are actually more effective in colder conditions when they can work without overheating. Panels that are durable, and that can withstand high temperatures, will have greater overall efficiency and lifespan.


Solar panels need a protective coating on them to ensure their longevity. What's challenging, however, is that this protective coating shouldn't reflect any of the potential energy the solar cells are trying to capture. Higher-efficiency panels will have high-quality protective coatings that reflect the least light possible, increasing overall energy production.

Environmental Factors Affecting Efficiency

While solar panel efficiency is determined in large part by solar cell technology and the construction of the panels themselves, there are also a number of other real-world contributors to the overall amount of power your system will be able to generate.

Climate and Latitude

Climate and latitude have a large impact on the overall efficiency of your solar energy system. The closer you live to the equator, the more direct sunlight you'll receive on an annual basis. Climate factors in as well. If you live somewhere rainy or often covered by clouds, you won't get as much production out of your system.

Solar Panel Orientation

Similar to the role of latitude, your panel orientation will affect efficiency. If you live in the northern hemisphere, the best direction for your solar panels to face is south (and north if you're in the southern hemisphere), as this is how they will get the most direct sunlight. If your roof isn't at a great angle for solar, your system will be less efficient.

Dirt, Dust or Grime Buildup

This factor is particularly unappreciated — you might be surprised how much production you lose when you don't clean your panels. Fortunately, it's pretty easy to give your panels the routine maintenance they deserve to keep your home powered on clean energy.

How to Find the Most Efficient Solar Panels

Solar panel manufacturers continue to make large strides in solar panel efficiency as the industry continues to recognize its value. Highly efficient, monocrystalline panels are ideal for residential solar systems, as those projects typically have the least amount of space to work with. For this reason, most top solar companies should be certified to sell and install the most efficient solar panels listed above.

If you're looking to invest in high-efficiency panels, we recommend getting in touch with solar installers near you to inquire about their product portfolios. Now that you know so much about solar efficiency and why it matters, you'll be well prepared to find the proposal with the best value for your money.

To start getting in touch with certified local installers, you can use this tool or fill out the form below.

FAQ: Most Efficient Solar Panels

What is the most efficient solar panel?

As of publication, SunPower's M-Series panels hold the throne for the most efficient solar panels on the market, at 22.8% efficiency. Though there are more efficient solar panels in development, it will be some time before they're available commercially.

Can solar panels be 100% efficient?

"In science, nothing is ever 100%." — Michio Kaku

For a common solar panel to be 100% efficient, it would have to convert all potential energy that strikes its surface area into AC electricity. This means a solar panel would need to absorb no heat, cover every spectrum of light, not reflect any light, and not lose a single electron over decades of complex chemical processes.

However, there is research being done on what's called "multiple exciton generation" (MEG). Researchers claim solar cells have surpassed 100% efficiency using MEG, a process by which "a single high energy photon can produce more than one electron-hole pair per absorbed photon. The extra efficiency comes from quantum dots 'harvesting' energy that would otherwise be lost as heat." So, 100% efficiency may be attainable if we think outside the box.

Which solar panels produce the most electricity?

Another way to phrase this might be, "which solar panels are the most powerful?" This is measured by wattage. This past year was a landmark year for the power of solar panels, as some commercial and industrial panels from brands like Jinko and Trina are nearing 700 W.

Karsten Neumeister is a writer and renewable energy specialist with a background in writing and the humanities. Before joining EcoWatch, Karsten worked in the energy sector of New Orleans, focusing on renewable energy policy and technology. A lover of music and the outdoors, Karsten might be found rock climbing, canoeing or writing songs when away from the workplace.