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DIY solar panels: pros, cons and installation guide. Home pv panels

DIY solar panels: pros, cons and installation guide. Home pv panels

    Home pv panels

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    Solar electric systems are the ideal way to produce your very own power, cutting your monthly energy bills, allowing for energy independence, or even going completely off the grid.

    These systems are available in small and large sizes, can be custom sized to fit your household, and allow you great independence and energy savings. In many areas, the electricity produced can even be sold back to the grid for even more savings or a profit.

    Benefits of Solar Electric PV Systems

    Cut your electric bills: The energy from the sun is free, so once you’ve paid for the initial cost of your solar pv system, you generate free electricity – with no cost to you.

    Generate money with your PV system: In many areas, there are SRECs (Solar Renewable Energy Credits) that you generate for the power your PV system produces – even if you use the power. These credits can be sold every month, generating income – while still reducing your electric bills.

    Sell energy to the grid: With grid-connected PV systems, you can often sell the energy you don’t use back to the power company (aka, the grid). This often results in a credit, or even income paid to you by the power company.

    Contribute to a clean environment: Solar energy in all forms is clean, and contributes to a reduced carbon footprint. Renewable energy, unlike fossil fuels, doesn’t release harmful gases or pollutants. By installing a solar PV system, you contribute to reducing your own personal carbon foot print, as well as help sustain a clean environment for the planet.

    Energy independence: A solar PV system gives you independence and freedom from electric rate hikes and cost increases, and many systems can be configured to provide power during storms, blackouts, and other power outages. No noisy or costly gas generators, or inconvenient power losses, a solar PV system can give you the energy independence you deserve.

    How a PV System Works

    (1) When sunlight strikes the solar array, the panels begin to produce electricity. The electricity produced by solar PV panels is direct current (DC) electricity.

    In order for your home to safely use this energy, it must first be converted from DC to AC (alternating current), which is what most homes use today.

    (2) The DC power is fed into a solar inverter, where it is converted from DC to AC so the electricity will be compatible. Different types of solar inverters are used, depending on application.

    For example, micro-inverters are a type of solar inverter that is mounted on the solar panel itself.

    AC solar panels are also used, which produce AC current, and do not need to be run through a separate inverter. String inverters are very common as well, as they allow a number of PV panels to be fed into one device for conversion.

    (3) The AC power is then fed into your service panel, so that the power can be supplied to various loads, such as your lights, refrigerator, or TV.

    (4) When a surplus of power is generated (you are producing more power than you are using), the excess electricity is fed through your utility meter. In some areas, there is a separate utility meter for power being produced.

    (5) This energy is then fed back to your power grid, which the power company will buy back from you. This can result in a credit, or in generating income in some areas, for energy you aren’t using.

    This is just one example of a grid-tied solar pv system. Other configurations, such as off-grid systems, or systems with battery backup are used as well. Grid-tied systems, however, are by far the most commonly installed PV systems. For more information on other types of systems, please contact us.


    Solar Panels Plus offers complete home solar electric PV systems for locations all over the USA. These solar PV systems have been engineered and packaged to seamlessly integrate into your home’s current electrical grid.

    Available in a number of sizes and power outputs, these packages allow you to generate your own power for free, and drastically cut your electric bills. regardless if your power consumption is small or large.

    These packages include the following components:

    Solar PV Panels

    The solar PV panel array is the primary component in any home solar pv system. The PV panels used can be specified as Buy American Act Compliant, and come backed by a full 25-year warranty. ensuring reliable, free energy generation for decades to come.

    These panels are UL tested and certified, complying with international safety standards. They are available in various sizes, such as a 230W and a 270W panel. These PV panels are also eligible for federal, state, and local rebates. drastically reducing the upfront cost of your entire solar pv system. For a full listing of incentives, please visit

    Solar PV packages are sized for various electrical loads, and can contain as little as 6-8 PV panels, or as many as 20 or more PV panels. Various sizes are available depending on your electrical consumption, or we can quickly and easily size a custom package to meet your specific electrical demands and budget.

    Our solar AC module can also be included in packages, making solar PV more affordable than ever before.

    Solar Inverter

    The solar inverter is another critical component to a home’s solar PV system. The solar inverter takes the direct current (DC) power generated by PV panels, and converts it to usable alternating current (AC) so it can be safely used to power appliances and items in your home. or fed back to the power grid.

    Solar inverters are available in two types of technologies. string inverters and micro inverters. Both types of solar inverters are included in our packages, and are available for home application.

    String inverters allow all the solar panels to be wired together, and then fed into a single device. Our string inverters are American Made, high efficiency, and are backed by a full 10-year warranty.

    Each string inverter has been sized to match the number of panels in each package, taking into consideration temperature variances, voltage, amperage, and the voltage and phase of the home.

    Options are available for these inverters, such as remote web based monitoring.

    Micro-inverters are mounted onto each individual pv panel at the time of installation, inverting the electrical current from DC to AC right at the source. Our micro inverters are available from a number of manufactures, such as the well-known Enphase. They are reliable, high performance, and sized to match the number of panels in each system.

    Micro-inverters also allow for increased customization options, giving you the freedom to get the exact power output you want for your home. Or you can come back later and add more panels easily, allowing you to slowly build up the size of your solar PV system over time.

    PV Racking

    Each package includes a set of PV racking for your system. The racking is crucial for safe and easy mounting of your PV panels. Various options are available for racking, increasing the flexibility of where your PV panels are installed.

    Roof mounting, ground mounting, and pole mounting options are just a few of the types available for your home PV system.

    Ground mount or pole mount PV mounting systems can be used to install PV panels if you don’t have the roof space or if shading is a problem.

    Charge Controllers

    Charge controllers are included in our off-grid and battery backup pv systems. Charge controllers are a crucial part of any pv system that includes battery backup for storage.

    These controllers use the latest technology to improve the lifespan of your batteries, and give you optimal charge for longer. They allow you to get the most out of your investment in an off-grid or battery backup system.

    PV Components Balance of System

    A number of other items are also included in each package that is built for your solar installer. This allows your installer to shop at a single place, and receive one shipment with everything he needs for a fast, safe, and simple install. Batteries, wiring, cables, and much more are available. For more information, please contact us.

    DIY solar panels: pros, cons and installation guide

    To save money, it’s no surprise that many homeowners are considering “do it yourself”, or DIY, solar. You can install solar panels yourself, but there are some advantages and disadvantages to doing it alone. In this article, we’ll break down the top pros and cons that you need to know about do-it-yourself solar panel systems before making a decision.

    Can you install solar panels yourself?

    A solar panel system is complicated, which is why so many companies across the U.S. specialize in providing professional solar installation services. However, that doesn’t mean you can’t build your own solar panel system – you can install your own panels, a DIY solar panel setup can be a viable option for some solar shoppers wanting to tap into renewable energy.

    According to data from the EnergySage Marketplace, the average cost of going solar for homeowners (after accounting for the federal tax credit) is about 20,650 in 2023. Of that amount, design and installation labor costs contribute about 10% of the total bill; this 10% is what a DIY solar installation will save you since you’ll still have to buy the equipment and components yourself. Regardless, it’s still tempting to look into building your own solar panel installation to save money and be in full control of your home renewable energy project.

    Your solar energy system should continue to generate electricity for 25 to 35 years, so you must consider both the upfront costs and the relative financial benefits for all of your solar options. If you buy a home solar kit like the ones for sale at Costco or Home Depot, it may be less expensive per watt, but you aren’t getting the same quality equipment that solar installers can offer you. For the most part, solar installers buy from equipment distributors that don’t sell to the general public – and they’re often getting lower because they’re able to buy in bulk and have access to the best solar panel brands. Going for the more expensive option now may end up saving you money in the long run because you’ll likely have a system built to last a few decades, offsetting your monthly electric bills.

    Pros and cons of DIY solar panels and solar panel kits

    DIY panels can be a great option for going off the grid and some small home applications. For powering your entire home, however, it may be in your best interest to go with a professional installer.

    DIY solar pros and cons

    Pros of DIY solar panelsCons of DIY solar panels
    Provides more energy independence for homeowners by not being tied to the electricity grid. Require much more maintenance that would otherwise be covered by an installer warranty.
    Effective in powering smaller items like RVs, boats and other appliances For an entire home, installation may be difficult for an individual without the knowledge and experience of a professional installer.
    Allows homeowners to save roughly 10% on the overall cost of installation that would otherwise go towards labor. DIY installation may be illegal where you live according to local zoning laws.

    Most home DIY all-in-one solar panel solar kits (including items like solar batteries, and inverters) are designed for off-grid use, which means you can’t use them and remain connected to your utility. If you’re an average homeowner, going off-grid is probably not in your best interest – being able to access utility-generated electricity is important if your solar array doesn’t produce enough electricity to meet your needs at all times of the day throughout the year.

    However, home solar kits can be a good solution if you’re not trying to power your entire home. RVs, boats, and the increasingly popular tiny houses are all opportunities to explore do-it-yourself solar because they are already off-grid and mobile. Storage kits are also a good option for backup to help in the case of a blackout and can contain battery banks and battery systems.

    If you want to install a DIY solar project, compare several options beforehand. Grape Solar is a major manufacturer (among others) and offers a few different DIY products and components for both grid-tied and off-grid systems, which you can find more information on below.

    DIY solar options

    ProductSystem size (watts)System costDollars per wattRetailer link
    Grape Solar 400 watt PV solar panel kit 400 588 1.47 Home Depot
    Grape Solar 600 watt PV solar panel kit 600 857 1.42 Home Depot
    Renogy solar 12-volt/24-volt premium kit 800 1,350 1.69 Renogy
    ECO-WORTHY off-grid solar panel kit 800 1,090 1.36 Amazon

    When you decide on DIY solar panels, remember that you get what you pay for. A home solar kit may be less expensive, but solar installers offer tremendous value for a relatively little additional cost (remember that 10% figure?). When it comes to installing an expensive electrical system on your property, finding someone who knows what they’re doing can save you both time and money in the long run.

    Some of the best solar installers have been in the business for decades – an experience that no amount of online research or DIY guides can replicate. Every state requires that installers are licensed and qualified to install solar, and independent certifications like the North American Board of Certified Energy Practitioners (NABCEP) Solar PV Installation Professional Certification ensure that the company you choose to work with has an intimate understanding of the process. Because of this, they can provide experienced insight and help you assess what equipment is the best fit for your property and whether a battery system is right for you.

    Your solar installer will also help you complete and file the permits and applications that you need to submit to get your solar power system up and running. This is particularly important because your utility won’t let you connect your system to the grid without a sign-off from a certified electrician.

    Because of your solar installer’s experience, they’ll also have a strong understanding of the financial incentives for solar available in your area, and might even be able to help you save more money by finding any rebates and tax incentives that you may have missed. Lastly, it is important to note that many equipment manufacturers will only honor their warranties if a qualified installer installed their equipment. Many installers will also offer an additional warranty to back up their work, too.

    The 6-step guide to DIY solar panels: how to install solar panels

    The DIY solar panel installation process can be simplified into six major steps:

    Purchase your solar equipment and components (solar panels, batteries, inverters, racking, etc.)

    Equipment and components including panels can be purchased with help from the EnergySage Buyer’s Guide. You can compare panel, battery, and inverter models based on specs like efficiency, warranties, and more.

    Install the racking or mounts for the panels on a roof or the ground

    Once you have the necessary equipment, designs, and permits in order, it is time to install your equipment. For roof mount systems, this begins with installing your racking and mounting equipment. To start, mark where your system will be installed, drill where lag bolts will be put in place, caulk the holes, put in lag bolts, and lock rails onto them. For ground mount systems, the steps are similar, only the panels will be installed at the ground level on some type of racking system.

    Install your equipment

    The first items to install are the solar inverters, which convert the electricity generated by your solar panels into usable electricity. After these are installed using provided bolts, you will need to connect a grounding wire. This is a piece of copper wire across the rails that serves as a safety precaution against lightning strikes and other faults. After this, you can attach your solar panels to your racking equipment.

    Connect to your main electrical board

    After you have fully installed your panel and system, be sure to schedule an inspection with the local construction authority closest to you. This will ensure that your system complies with local ordinances. Once you pass this inspection, you can apply to connect to the grid. The local utility company will give you a meter to record your power exports.

    Get in touch with your utility company and request permission to turn on (PTO) if necessary in your area

    From there, turn on your system after you have the proper approval and check how the system is functioning with a solar monitoring app.

    Maintenance of DIY solar panel systems

    One of the benefits of working with a certified solar installer is the warranty that comes with their service. Solar panel manufacturers provide a range of warranties that guarantee you will have support and coverage in the unlikely event of an issue caused by unusual circumstances, such as large hail or falling tree branches. Power output warranties guarantee that panel performance won’t fall below a specified level over the term of the warranty (usually 25 years). For instance, a manufacturer might provide a warranty to guarantee that peak power output won’t fall below 85% for 25 years.

    Frequently asked questions about DIY solar panels

    If you’re considering a DIY solar panel kit, but still have concerns about the best options, process, and general cost, check out a few of the most common questions we encounter when talking to solar shoppers:

    DIY solar panels may be tempting to install, but their long-term worth may be up for debate due to quality alone. Typically, a solar panel system should continue to generate electricity for 25 to 35 years, so it’s important to invest in quality equipment and a reputable installer. If you purchase a home solar panel kit from a retailer, you may be paying less per watt, but you’re not going to get the same efficiency or quality that professional installers usually offer with their products.

    You’ll also likely forgo any warranties that come with your solar panel system, as warranties often only apply when the system is installed by a certified installer. It’s also important to mention that if you still need to rely on some utility power and remain connected to the grid, DIY solar panels are typically not worth it. They are best used for small off-grid applications, like RVs, where a solar generator or solar battery bank can provide you power when you otherwise may not have access.

    As a DIYer, you don’t need to be an electrician to install solar panels. It’s certainly not illegal to go the DIY route if you choose to. However, when it comes to installing a costly electrical system on your property, we recommend relying on professionals with technical know-how —their experience is invaluable and it can make a huge difference in the overall quality and performance of your system. Plus, solar installers will help you fill out permits and file important paperwork that you might not otherwise know is required.

    You can find reliable DIY solar panels at retailers like Home Depot or from manufacturers like Grape Solar, for between 6,000 to 11,000, depending on your system size needs. For lower cost options, some manufacturers sell DIY solar panels on Amazon for anywhere between 1,600 to 2,500. You may be looking at additional costs if you want to install a solar battery and charge controller system as part of your DIY project.

    Should you install solar yourself or hire an installer?

    If you’re wavering between a DIY solar system and hiring a solar installer, getting a ballpark estimate for an installation may help you in your decision process. With our Solar Calculator, you can see upfront cost and long-term savings estimates based on your location and roof type to determine if a solar installation is the best choice for you. If you’re looking to get quotes from local contractors today, be sure to check out the quote comparison platform in the EnergySage Marketplace.

    reading on EnergySage

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    Everything You Need to Know Before Installing Solar Panels on Your Home

    A SunPower expert shares common misconceptions, surprising savings, and proper maintenance.

    Making the switch to solar power has never been easier — or more appealing. That’s in part due to the recent passage of The Inflation Reduction Act says Nuala Murphy, Vice-President of Customer Care for SunPower, a home solar and energy services company. The legislation contains more than 300 million earmarked for clean energy spending, some of which will come back as tax incentives and credits to homeowners who choose to purchase solar systems.

    All of that sounds great, but, as with any home upgrade, you’re probably wondering about what the process entails. Read on for Murphy’s answers to questions about cost, savings, installation, and other considerations when it comes to harnessing the sun to light up your home.

    How do I know if my home is solar ready?

    Companies like SunPower have systems and processes in place to guide you at every step of installation, including the primary phase of research. “A custom analysis of your home will ensure our team can design a system with the intent meet your energy needs for today and the future,” explains Murphy.

    By assessing factors including the position of your home on its lot, SunPower will determine details like how many panels your roof can accommodate and what the ideal arrangement for the panels would be. They’ll also examine your current energy usage and help you think about what that might look like in the future; a family with five kids living at home will have different needs than a pair of soon-to-be empty-nesters.

    If you see cloudy days as often as sunshine, that doesn’t mean your home is not a contender. Murphy notes that it’s a myth you need to live in an especially sunny climate to take advantage of solar power.

    “There are about 100 million homes all across the U.S. that are great candidates for solar,” she says. “It’s also important to remember that most roof types in use in the U.S. — like asphalt, shingle, and clay tile — are capable of holding solar panels.”

    Not sure where to start? SunPower’s Design Studio tool enables you to see what your home would look like with solar panels, and get an estimate of your energy savings by typing in your address.

    How much do solar panels cost?

    The price of installing a solar system varies from house to house, based on needs and location. The average cost of a system is about 20,000, which can be paid up front or financed through monthly installments. If you’re paying for the system outright, it has the potential to be a major asset if and when you decide to sell your home, with research showing that installing a system can boost its value, especially in certain states.

    But financing a system means you might start to see savings even quicker, as the payments are offset by decreased electricity. According to SunPower, many customers who finance their systems via loan start seeing utility bill savings as soon as their system is activated.

    Can solar take me completely off the grid?

    Possibly, depending on how much energy you use, how many panels you have, the climate where you live, and if you opt for battery storage. Even if you reach that milestone, as Murphy explains, there’s reasons to stay connected to the grid: “You may be able to run all of your electricity needs during daylight on your solar system and even generate excess power, which can be sent back to the grid for credits on a future energy bill. That then helps the community by lessening the load on grids in times of bad weather and high demand.”

    There’s also a growing market for backup battery systems that enable homeowners to bank any extra energy generated by their home’s solar panels. For example, SunPower’s SunVault 26-kilowatt-hour battery system can store enough power to run essentials like lights and refrigerator as well as items that make life more comfortable like and HVAC a washer/ dryer during an outage.

    When combined with a solar storage system, solar power can give you peace of mind that you’ll be able to keep your electricity on, even in a blackout. You can also deploy energy stored in a battery during times when grid energy rates are highest for another way to help save money on electricity bills.

    I’ve gone solar. Now what?

    Many people have questions about the maintenance of a solar system. Your provider can share a full checklist, says Murphy, but she notes that a key tip is trimming back trees to make sure the system is working at its full potential, and avoid falling branches or leaves causing issues. Most crucial, says Murphy, is working with a reputable company that you are confident will be around for the life of the system.

    Next, consider a warranty to give you peace of mind and protect your investment if something unforeseen should go wrong. When shopping for a warranty, look for one that covers everything from performance to parts, and make sure you fully understand the terms.

    Solar systems typically last between 25 and 30 years, so with a properly installed, well-maintained system, your home’s energy future can look bright for decades to come.

    Most Efficient Solar Panels Of 2023 (Guide)

    Samantha covers all topics home-related including home improvement and repair. She previously edited home repair and design content at The Spruce and HomeAdvisor. She also has hosted videos on DIY home tips and solutions and launched multiple home improvement review boards staffed with licensed pros.

    We earn a commission from partner links on Forbes Home. Commissions do not affect our editors’ opinions or evaluations.

    Installing the solar panels for your home is an excellent way to conserve energy and lower utility bills. However, it’s important to understand the differences in the fabrication of solar panels in order to choose the most efficient solar panels for your commercial or residential installation. For those looking to install solar at home, we’ve searched for and found the best solar companies for consideration.

    THIS IS AN ADVERTISEMENT AND NOT EDITORIAL CONTENT. Please note that we do receive compensation for any products you buy or sign up to via this advertisement, and that compensation impacts the ranking and placement of any offers listed herein. We do not present information about every offer available. The information and savings numbers depicted above are for demonstration purposes only, and your results may vary.

    Power Your Home With Solar

    Find a network of trusted installers for your solar system, solar panels and electricity needs. Find a solar panel installer today!

    How Efficient Are Solar Panels?

    The efficiency of solar panels is determined by the amount of sunlight reflected on the panels’ surface, which is then transformed into electrical or thermal energy. Previously, the average efficiency of solar panels was around 15%, but thanks to advancements in photovoltaic technology, the efficiency of solar panels is currently between 15% and 22%. High-efficiency solar panels can even reach nearly 23%. As a result, 370W is the typical power rating of a panel, an improvement from 250W. Two factors go into determining solar panel efficiency: photovoltaic (PV) cell efficiency and total panel efficiency.

    Panel Efficiency

    PV cell efficiency comes as the result of the cell design and silicon type, while cell layout and configuration along with the solar panel size are the basis for total panel efficiency.

    Cell Efficiency

    Total panel efficiency is determined by the maximum power rating under standard test conditions divided by the total area of the panels (in meters).

    Most Efficient Solar Panels

    While the most efficient readily available panels all share efficiency percentages above 20%, Canadian Solar’s HiHero series panels are tied with SunPower for the highest efficiency rating at 22.80% under optimal conditions.

    However, the Canadian Solar HiHero 445 H-AG solar panel has a temperature coefficient of 0.26%. Compared to SunPower’s coefficient of 0.29%, the HiHero edges out its competition when the temperature rises over 77 degrees Fahrenheit.

    Canadian Solar HiHero High Efficiency Heterojunction (HJT) Cell Module 445H-AG -0.26 22.80%
    SunPower 420-440W Residential AC Module M-Series: M440 -0.29 22.80%
    Q Cells Q.Peak Duo Blk ML-G10 £410.00 -0.27 20.90%
    REC Solar REC Alpha Pure-R REC430AA PURE-R -0.26 22.30%
    Panasonic Solar EverVolt™ Series EVPV410H -0.26 22.20%
    Silfab SILFAB Elite SIL. 380 BK 0.38 21.40%
    Residential panels with data correct as of April 2023

    Canadian Solar

    Canadian Solar offers consumers ten solar panel model series. Its lineup of HiKu Mono PERC panels on one end of the spectrum provides up to 425 watts at 20.9% efficiency, while at the other end, the company’s BiHiKu7 models start at 580 watts and continue through six more wattages to reach a whopping 610 watts.

    However, the company’s most efficient solar panel is its HiHero 445 H-AG model, which features a 445-watt capacity at a 22.8% efficiency rating and a 0.26% coefficient rating.


    SunPower offers three lines of residential panels along with components and energy storage systems. The company’s M series solar panels consist of five models that range in efficiency from 21.7% in the M420 model to the highest in our review, the M440, with a 22.8% rating.

    SunPower’s two other series are the X and U lines. The X lineup uses the company’s own Maxeon technology and ranges from 21.2% to 22.7% in efficiency. The U series is SunPower’s most recent budget-friendly addition that steers away from using Maxeon panels but still comes with similar warranty protections.

    Q Cells

    Q Cell’s residential panel selection includes several models in the Q-Peak Duo BLK ML-G10 and the Q-Peak Duo BLK-G10 lines. The BLK-G10 series features panels that range from 350W to 370W with efficiency ratings from 19.5% to 20.6%.

    The ML-G10 is Q Cell’s most recent lineup featuring higher watt ratings and slightly higher efficiency. Panels in the series include a 385W model with 19.6% efficiency and five more models. The most powerful one in the series is a 410-watt panel with 20.9% maximum efficiency and a temperature coefficient of 0.27%.

    REC Solar

    REC Solar provides five solar panel series to choose from—Starting with its 360W to 375W N-Peak 2 series and increasing in wattage capacity through each series. Its most powerful and efficient panel is the company’s Alpha Pure-R, featuring 430 watts of power rated at 22.3% efficiency with a coefficiency percentage of 0.26.

    Panasonic Solar

    Among numerous industries that Panasonic is involved in, the company offers a selection of 15-panel models in six series variations in its solar energy sector. The collection, called Evervolt, consists of residential solar panels with watt ratings from 350 to 410.

    The highest wattage Evervolt H Series Solar Module offers 410 watts with a 22.20% efficiency rating and a 0.26% temperature coefficient.

    Silfab Solar

    Silfab’s solar panel offerings include two residential series, Silfab Prime and Silfab Elite. Models available in both series have efficiency ratings topping out at 21.4%. The company’s most powerful panel, the SIL-410 BG churns out up to 410 watts with a coefficiency rating of 0.377%

    How You Can Check Solar Panel Efficiency

    Monitoring your solar panels’ performance and efficiencies allows you to compare calculations to keep an eye out for panel degradation, or notice sudden drops in efficiency that could indicate a problem with the system.

    To calculate the efficiency of an individual panel, you’ll need to measure the surface dimensions and determine the total production area in meters squared. You’ll also need the current power production amount in kilowatts.

    There are several ways to determine the kilowatt output. If you’re looking for the panel’s potential, simply use the panel watt rating for the calculation and divide by 1,000. For more accurate testing, take the wattage number from your solar meter or use a multimeter to measure volts and amps. Multiply the two results to arrive at the total watts. Divide the watts by 1,000 to reach the kW measurement.

    With those two numbers, divide the panel output by the total area of the solar panel surface in square meters. Multiply the result by 100. The total is your current efficiency rating of the panels you’re testing.

    For example, a solar panel that measures 182 cm by 106 cm has a surface area of 1.82 m x 1.06 m or 1.93 square meters. If the panel is producing 400 watts or 0.40 kW. Dividing 0.40 by 1.93 equals 0.207. Multiply by 100 for an efficiency reading of 20.7%.

    Efficiency by Solar Panel Type

    There are three types of solar panels that are most often used in commercial or residential installations: monocrystalline, polycrystalline, and thin-film. Here is a brief explanation of each, as well as for what applications they are most useful:


    Monocrystalline solar panels are often touted as the most efficient option and are often installed for larger energy systems in commercial and residential properties. However, panel sizes do vary; therefore, monocrystalline can be used in smaller installations as well.


    • Made out of silicon with a high purity rating, boosting their efficiency to 15% to 23%
    • Don’t require as much space as polycrystalline and thin-film panels
    • Monocrystalline panels can last upwards of 25 years due to the stable and inert properties of the silicon


    • Price point is high because of their complex construction
    • Not a good choice for cold-weather climates, as snowfall can damage the solar cells and cause the system to fail.

    Monocrystalline brands: SunPower, LG, and Panasonic


    Like the name suggests, polycrystalline solar panels are constructed from multiple pure silicon crystals that are melted together. crystals aren’t always better, though. Polycrystalline panels are actually less efficient than their monocrystalline counterparts. They are, however, made in a variety of power settings ranging from 5W to 250W and higher, making them a good choice for both small and large-scale installations.


    • Process to create them is simpler, so they are less expensive than monocrystalline
    • Less waste after the melting process, making them better for the environment
    • Durable and long-lasting, just like monocrystalline solar panels, so they are a good choice for budget-minded homeowners


    • Lower efficiency (13% to 17%) because the silicon used to make them is lower in purity.
    • Take up more space to produce the same level of power as that of monocrystalline cells.

    Polycrystalline brands: TrinaSolar and YingliSolar

    THIS IS AN ADVERTISEMENT AND NOT EDITORIAL CONTENT. Please note that we do receive compensation for any products you buy or sign up to via this advertisement, and that compensation impacts the ranking and placement of any offers listed herein. We do not present information about every offer available. The information and savings numbers depicted above are for demonstration purposes only, and your results may vary.

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    Though they are lightweight and easy to move, thin-film PV cells—which are not made of silicon—are the least efficient type of solar panel. Use them only for installation that won’t need to produce too much power; flexibility and portability are the two top factors with these.


    • Easier and less expensive to produce
    • Excellent for solar transportation applications, such as panels that are installed on bus rooftops and refrigeration for cold-storage trucks


    • Not a good choice for rooftops, as they require a large space to harness enough solar power for energy output.
    • Weaker so they break down more quickly than crystalline panels. Only short warranties are available for thin-film panel installations, which is something homeowners especially should consider depending on how long they plan to stay in their homes.

    Thin-film brands: Stion and Solopower

    Factors That Impact Solar Efficiency

    Several things can affect solar panels’ efficiencies, such as the type of solar panel, the inverter efficiency, thermal cycling, etc. Here are some factors to consider before purchasing a solar panel system:

    Solar Panel Types

    When figuring out which type of solar panel is right for your home, the first thing to do is to get acquainted with each type, its construction and its efficiency:

    • Monocrystalline Solar Panels: The most popular and most efficient type of solar panels, monocrystalline solar panels, are popular amongst residences and businesses. They are made of individual pure silicon crystal and can generate between 300 and 400 (sometimes even more) watts of power each.
    • Polycrystalline Solar Panels: Polycrystalline panels are made from several pieces of silicon that are separated into fragments and melted together. They are slightly less expensive but also less efficient than monocrystalline solar panels.
    • Thin-Film Solar Panels: Thin-film solar panels can be made of three different materials: Amorphous Silicon (a-Si), Cadium Telluride (CdTe) and Copper Indium Gallium Selenide (CIGS). Each type of thin-film solar panel is less expensive than both crystalline panels but is also less efficient.

    Sunlight Hours

    While solar panels can generate electricity in various light conditions, even on cloudy days, their efficiency rates drop dramatically during hours with little light available. Generally, about four hours per day of direct sunlight is necessary to achieve the optimum performance of your solar panel array.

    However, during the remaining daylight hours, when sunshine is present but not direct, your solar panels can still generate substantial electrical power. The same is true of overcast days.

    The total number of hours of any kind of sunlight per day directly affects the overall efficiency of your panels in the short term. There are no long-term effects to solar panels that don’t receive an optimal amount of sunlight daily.

    Inverter Efficiency

    The inverter is what converts general Direct Current (DC) to Alternating Current (AC) electricity, which is what your home runs on. Most inverter’s conversion efficiency is around 97% to 99%, so the energy loss is relatively minor.

    Temperature Coefficient

    Solar panel efficiency ratings are measured and recorded under laboratory conditions called Standard Test Conditions or STC. The lab conditions include measurements taken at 25 degrees Celsius (77F). The temperature coefficient rating for solar panels measures the percentage of the panel’s efficiency loss when its surface rises above that temperature.

    For each degree Celcius that the panel’s temperature rises above 25, the panel’s efficiency will lessen by the coefficient rating percentage.

    For example, SunPower’s most powerful solar panel, the M440 produces a maximum output of 440 watts under ideal conditions at 25 degrees Celsius. Its efficiency rating at that temperature is 22.8%. The panel has a temperature coefficient rating of 0.29%.

    When the panel temperature increases by 10 degrees Celsius (50F), which isn’t uncommon under hot sunlight, its efficiency will decrease by 2.9%, meaning its overall efficiency drops below 20%. Essentially, it produces less power when it’s hot.

    Damp Heat

    Solar panel damp heat testing puts a subject solar panel through a rigorous test in which it’s sealed in a chamber kept at 85 degrees Celsius and 85% humidity for 1,000 hours. The test aims to recreate and accelerate the harsh conditions that the product will experience over several years of direct exposure to the elements.

    While damp heat testing doesn’t directly measure the effects of weather on a panel’s efficiency, the process tests the unit’s integrity related to delamination and corrosion, which, in turn, affect the panel’s overall efficiency.

    Thermal Cycling

    Thermal cycling tests your solar panel to see if it can withstand a wide temperature range. Solar panel components can expand and contract during Thermal Cycling, which may affect their efficiency.

    Solar Panel Orientation

    South-facing roofs are ideal for generating electricity with solar panels. West-facing roofs are the next best option, and east-facing roofs are next. If you have a north-facing roof, you may want to reconsider. West and east-facing panels will generate up to 15% less energy than a south-facing array while north-facing panels can lose as much as 20%.

    Identifying the prime installation angle towards the sun is essential to optimize solar panel performance. The exact angle degree varies based on latitude but generally lands between 30 and 45 degrees. The installation angle affects how much time per day the panel receives direct sunlight.

    The installation angle is most impactful during winter when the sun is lower on the horizon. Correct orientation and angle during winter can yield around 50% more energy than panels installed without the same consideration.

    Environmental Factors That Impact Solar Efficiency

    In addition to the typical factors, your environment is also something to consider before purchasing a solar panel system. Environmental factors such as average temperature, weather conditions and even dust and dirt build-up also impact solar efficiency.


    Solar panels work best at about 77°F, with peak efficiency between 59°F and 95°F. However, when the surface temperature of your solar panels gets higher than 149°F, solar panel efficiency can decline.


    The color of the back sheet that protects the panels can also affect efficiency. For example, while black might look more attractive for a protective back sheet, the color absorbs more heat. This results in higher temperatures and, therefore, a reduction in the total conversion efficiency, so other colors like dark blue, green or even patterns might be a better option for your solar panels.

    Extreme Weather Conditions

    Anything that stands between the sun and your solar panels reduces the amount of solar energy your system produces. Therefore, extreme weather conditions such as snow, wind, rain and hail can potentially affect your solar panel’s efficiency.

    Since snow accumulates onto the surface of your solar panels, the sun cannot penetrate the panels, which will ultimately affect the efficiency of your system.

    Since the wind could potentially cool your solar panels down, the wind can make them more efficient as long as the sun is still shining on them.

    Rain does not affect your solar panel efficiency; however, rain clouds could affect how much sun reaches them. However, constant rainstorms help keep layers of dirt and dust from covering the panels and blocking the light, which could decrease solar energy production.

    Unlike snow and rain, a hail storm can present slight problems for your solar panels. Although solar panels have been tested to withstand hail-like conditions, there is a chance of solar panel damage from a hail storm.

    Dust and Grime Build Up

    As time passes, your solar panels are bound to have some dust and grime build up due to the elements. If there is a layer of dust and grime on your solar panels, the sun will not be able to effectively reach the panels, causing a lapse in efficiency until the panels are cleaned.

    THIS IS AN ADVERTISEMENT AND NOT EDITORIAL CONTENT. Please note that we do receive compensation for any products you buy or sign up to via this advertisement, and that compensation impacts the ranking and placement of any offers listed herein. We do not present information about every offer available. The information and savings numbers depicted above are for demonstration purposes only, and your results may vary.

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    Why Is Solar Panel Efficiency Important?

    Solar panel efficiency is measured by the percentage of sunlight that hits your panel and is converted into usable electricity. Therefore, efficiency is most important when roof space is limited.

    For instance, if you have limited roof space and cannot fit as many solar panels on your roof as you would like, it may make sense to pay more to install higher-efficiency panels to absorb as much sunlight as possible.

    However, lower-efficiency panels will produce the same energy as high-efficiency ones, but they’ll require more to do so and more space. Therefore, lower-efficiency panels can cover your electricity use and help you save money if you have the space to house them.

    The amount of power a panel with 15% efficiency can create can be as much as 100 watts less than a panel of the same size that can achieve 22% efficiency. In an average residential solar setup, the home could require up to eight additional 15% solar panels to generate the same power as 20 units at 22%.

    Why Aren’t Solar Panels 100% Efficient?

    A panel with 100% efficiency can transform all the light that hits the panel into electrical energy. However, since solar panels cannot absorb energy from the entire solar spectrum, they cannot convert sunlight into electricity with 100% efficiency. Specific wavelengths of light are reflected off the solar panels or lost altogether.

    What to Consider When Installing Solar Power Panels


    Solar panels can be costly upfront, which is why many homeowners do not take the decision to go solar lightly. The Center for Sustainable Energy reports that the installation can cost, on average, between 15,000 and 25,000. Polycrystalline solar panels are considered the most cost-effective choice in solar panel installations, but it depends on the type of panels and how many are needed for installation.

    solar, panels, pros, cons

    While your initial investment in solar panels can be recouped over the years, it might take longer for you to see back your money based on a number of factors, including energy usage and weather conditions; the latter might affect solar panel functionality.


    Solar-powered energy, not surprisingly, is more efficient in places where there is more sun exposure. Residential and commercial buildings in Southern California, for example, would likely reap the benefits of solar power more so than those in the cloudy Pacific Northwest. Still, even places that aren’t the sunniest can benefit from solar power, as cooler temperatures will cause the panels to create more power.

    Energy Usage

    If your energy bills are high, then it makes sense to install solar panels to reduce costs and to earn back the initial investment over time. However, if your energy usage is minimal, solar panel installation might not be worth the expense. It is also important to note that top efficiency is only achieved in top conditions and only at the beginning of the panel’s lifetime of use. As the solar panels age and are exposed to the elements, they will begin to perform less efficiently.

    Solar Installation Companies

    The company you choose to install your solar energy system is a crucial decision. While some installers use several solar panel and component manufacturers, many install just one or two brands. Ensure the installation company you choose is willing to install the solar panel brand of your choice and can service the system when necessary.

    solar, panels, pros, cons

    Solar Incentives

    The federal residential solar tax credit allows homeowners to deduct 30% of the cost of their installed solar energy system from their taxable income for the year. However, that’s just one of several incentives that may be available depending on your location. Look for local, state and regional incentives as well. Your solar installation company should be well-versed in helping you discover these benefits.

    solar, panels, pros, cons

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    THIS IS AN ADVERTISEMENT AND NOT EDITORIAL CONTENT. Please note that we do receive compensation for any products you buy or sign up to via this advertisement, and that compensation impacts the ranking and placement of any offers listed herein. We do not present information about every offer available. The information and savings numbers depicted above are for demonstration purposes only, and your results may vary.

    Frequently Asked Questions (FAQs)

    What is the highest efficiency solar panel?

    Currently, the highest recorded solar panel efficiency rating took place in a lab and is rumored to have reached over 40% efficiency. However, in more practical conditions, the most highly efficient solar panels available to homeowners is Canadian Solar’s HiHero 445 H-AG model.

    What is the most efficient type of solar panel?

    Monocrystalline solar panels are often considered the most efficient solar panel option. Therefore, they are typically installed for larger energy systems in commercial and residential properties.

    How does increased energy efficiency benefit you?

    Increased energy efficiency in solar panels has several benefits for homeowners.

    • Potentially fewer solar panels to purchase and maintain
    • Highly efficient solar panels produce more power in direct and indirect sunlight.

    What solar panel type has the highest efficiency?

    Monocrystalline solar panels are often considered the most efficient solar panel option. Therefore, they are typically installed for larger energy systems in commercial and residential properties.

    How many solar panels do you need?

    With a home of roughly 1500 square feet, it is estimated that 15 to 18 solar panels will be needed.

    Can you DIY a solar panel installation?

    It’s tempting to save money and install solar panels yourself, especially if you have numerous successful DIY projects under your belt. But installing solar panels is a project that is best left to the pros. Depending on the type of panel you choose, installation might require complex configurations that are otherwise difficult to install correctly without the training experience.

    Additionally, professional installation might be required to uphold the warranty. As with many projects, getting a professional to install a solar energy system means that it will be done right the first time so that you can begin reaping the benefits of it immediately.

    How long will it take to recoup the cost of solar panels?

    This answer will vary depending on a variety of factors, including the initial expense of the solar panel system, the amount of energy incentives and electricity usage. On average, though, it takes homeowners six to 10 years to recoup their initial investment.

    How long do solar panels last?

    Solar panels have an average lifespan of 25 to 30 years. However, they can last as many as 50 years. The longevity of solar panels depends on the weather conditions where they are installed, as snow, wind and debris from storms can affect their operation.

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