Top 5 Most Efficient Solar Panels (2023 Reviews)
By Karsten Neumeister /
In this EcoWatch guide on SunPower Solar Panels, you’ll learn:
We’ve helped thousands of homeowners save time and money when going solar by breaking down exactly what they need to know about SunPower’s solar panels. Let’s get started!
SunPower, which is based in California, is one of the most well-established names in the solar industry, and it’s best known for manufacturing the highest-efficiency panels available for home solar systems. In this SunPower solar panel review, we’ll be discussing what makes its panels (now actually manufactured by sister company Maxeon Solar Technologies) so appealing and why we think it’s the best brand you can invest in for your home.
We’ll explain why things like the high efficiency, long warranty coverage and durability matter to you, how they compare to the industry average and, most importantly, how they can save you money over time.
Yes, SunPower’s panels are widely considered the best in the industry for several reasons. They come at a high cost per watt, but they also deliver some of the most impressive performance specifications available.
Some noteworthy specs include:
In our opinion, the cost is well worth it, especially since the superior performance is likely to save you more on utility bills and pay for itself over time.
SunPower used to have a few different series of panels available, including the X Series panels, the A Series panels and the M Series panels. Since it split operations and pushed manufacturing to its sister company, Maxeon, it now offers two options, one of which is the Maxeon line.
The Maxeon line from SunPower—which includes the Maxeon 3 and Maxeon 6 panels—is the high-performance model available from the manufacturer. It comes in multiple sizes and different wattages, ranging from 420 watts up to 440 watts. You’ll get the highest efficiency rating of any solar panel in the industry at 22.8% if you opt for the 440-watt variety.
The peak efficiency is achieved, in part, by using a unique solar cell foundation that helps recuperate energy that normally would be lost to the environment. The solid copper foundation also helps improve durability, which allows SunPower to provide a warranty that’s nearly twice as long as the industry average.
These panels are all black, super sleek, and don’t have any visible grid lines. Since many homeowners care about the appearance of the panels on their roofs, this is another positive attribute of these PV panels.
The Performance line from SunPower—which includes the Performance 3 and the Performance 6 panels—is a slightly more affordable but less capable line of photovoltaic (PV) modules. These panels range from 370 watts up to 415 watts, with a peak efficiency of 21.1%, which is still above the industry average.
The Performance line of panels doesn’t use the solid copper foundation that the Maxeon line is best known for. Instead, it uses a traditional silicon and metal fiber foundation in its monocrystalline PERC solar cells. PERC (passivated emitter and rear contact) is a term used for advanced solar technology that is designed to boost performance by reducing the amount of sunlight lost by the panel.
While PERC technology isn’t unique to SunPower, the “hypercell” these panels use is. We’ll explain this tech in greater detail in the next section, but for now, just know that it helps boost durability and performance in all situations.
SunPower panels are known for their industry-leading specifications, and there are two innovative technological advances the company has made that lend themselves to such high performance.
Most notably, the panels in the Maxeon series are made with a new manufacturing technique using solid copper as a foundation rather than a baked sheet of silicon and metal shards. The solid foundation helps boost solar energy absorption, increasing panel efficiency.
The innovative solid copper backing also improves the durability of the PV cells. The M-Series is, as of this writing, the only panel in the industry to use this manufacturing technique.
SunPower also uses “hypercell” technology in its Performance series. It’s manufactured by layering six strips of a solar cell in a shingle formation and connecting them with an adhesive that’s designed to flex.
The flexibility improves durability and reduces the risk of damage, even with excessive temperature swings. SunPower released a short video about how this technology works and why it’s superior to the traditional manufacturing method. You can watch that below:
Overall, the technology SunPower uses is superior to anything else we’ve seen from manufacturers. The tech speaks for itself, too, as SunPower’s efficiency ratings, temperature coefficients, warranty coverage options and degradation rates are some of the most advanced in the industry.
SunPower solar panels outperform most other panels we’ve reviewed in both hot and cold climates.
Solar panels lose efficiency in hotter temperatures due to excited electrons escaping the PV cells. At present, this is unavoidable, but some companies have made advancements that help boost PV performance in high temperatures.
The metric used to explain solar module performance in the heat is called temperature coefficient, which is the percentage of the panel’s efficiency that is lost for every degree above 25 degrees (C) or around 77 degrees (F). The higher the temperature coefficient, the less efficient the panel will be in hotter climates.
SunPower has one of the lowest temperature coefficients on the market at just 0.27%. The only other panel we’ve seen below 0.3% comes from Panasonic. Ultimately, that means SunPower panels will lose less solar energy in hot temperatures, boosting performance and production.
In colder climates, solar panels tend to get more efficient due to fewer excited electrons escaping the cells. SunPower’s above-average efficiency rating helps boost production in the cold as well.
Watch Below: See Why SunPower Solar Panels Can Perform Well in the Shade
SunPower doesn’t manufacture inverters, microinverters, racking systems or electric vehicle (EV) chargers, but it did recently start offering the SunPower SunVault, which is a residential solar battery.
The SunVault comes in a few sizes, ranging from 13 kilowatts (kW) up to 52 kW (as part of the SunPower Equinox system), making it one of the larger battery options available. It has an above-average continuous power rating of 6.8 kW and an above-average peak power rating of 10 kW. That means these solar batteries can provide power to just about as many appliances or electronics at once as you might need.
The SunVault costs between $12,000 and $50,000, depending on the storage capacity you need, and it averages around $1,000 per kW of storage. The price per kW is slightly above average.
The upsides to the SunVault systems include the ability to maintain electricity seamlessly through power outages, and you can also boost your savings and get access to effective net metering if your state or utility company doesn’t offer it.
On average, SunPower panels cost around $3.30 per watt, which is well above the national average of $2.66 and above the average for tier-one panels, which hovers around $3.00.
Of course, your total price for a SunPower solar power system depends on your energy needs, the size of your home, your location and more. For the typical 9 kW solar array, you’re looking at a total of $29,700 before any perks, which would be $20,790 after the federal investment tax credit (ITC).
These numbers assume you have an average size home of around 1,800 square feet and consume the average amount of energy of just under 900 kW per month.
If you couple your SunPower panels with a SunVault battery, you can expect to pay a total of around $41,000 before perks for a 12 kW battery or $79,700 for a complete 52 kW storage system.
Luckily, the ITC also applies to SunVault components, so your total after the federal credit would average around $28,700 for the 12 kW system or $55,790 for the 52 kW system.
You can use our solar calculator to get a better idea of how much solar may cost to install for your house.
SunPower recently underwent some inter-company changes, and it now only handles solar installations. Its sister company, Maxeon, now technically handles all solar cell and solar module manufacturing.
If you choose to go solar with SunPower, you’ll have access not only to the leading solar technology but also to all of the typical payment options for PV equipment. SunPower accepts cash purchases, solar loans, solar leases and power purchase agreements (PPAs).
We strongly recommend a cash purchase if you can swing it, as this leads to the fastest panel payback period and the highest long-term energy savings. Of course, this is the least accessible option because it requires a large payment upfront that many solar customers cannot afford.
A solar loan is the next best option. You’ll pay interest, which will reduce your overall savings, but your upside will be greater than you’d see with a lease or PPA. Plus, you’ll own your panels, so you’ll eventually pay them off, at which point your monthly savings will skyrocket.
In a solar lease agreement, you rent your panels for a fixed cost per month and get to use the power they generate to reduce your utility bills. Most companies set up leases so that your total payment is lower, leading to immediate savings. However, lifetime savings are lower because this option doesn’t lead to panel ownership.
A PPA is similar to a lease, but instead of paying a monthly rental fee, you get your panels installed at no cost, and you agree to pay the installer for the power they generate. This option yields the lowest overall savings, but it typically provides a reduced monthly expenditure immediately.
Since SunPower panels come in well above the average cost per watt, most customers look for ways to save when converting to clean energy with this manufacturer. There are a few things you can do to save.
Second, we strongly recommend you take advantage of all of the solar benefits you can. The federal solar tax credit is available to all U.S. residents and could save an average of around $8,900 on a SunPower solar energy system. This is more than you’d save, on average, on panels from other manufacturers—an average of around $7,200.
There are likely other incentives available to you, like solar rebates, state tax credits, net metering programs and more. We recommend asking your installer or checking the Database of Database of State Incentives for Renewables and Efficiency (DSIRE) for more information.
Filing for these perks and rebates is usually a breeze because reputable installers will do a lot of the work for you. If you have to file for everything on your own, you’re still only looking at a few hours maximum, and the savings are substantial enough to be worthwhile.
Finally, we recommend choosing your payment option carefully and opting for a cash purchase if possible. You’ll save the most money over time with a cash purchase, followed by a solar loan and then a solar lease. A power purchase agreement is expected to save you the least on your SunPower system.
To put this into perspective, a cash purchase on a typical system saves around $22,400 on energy bills over the life of the equipment after the system pays for itself. Choosing a PPA or lease is still expected to save you money, but lifetime savings are usually closer to $5,000, which is significantly less appealing than what you’d see if you paid in cash.
First, we recommend shopping around and getting multiple quotes from installers in your area. SunPower handles installations in-house, but it also uses a massive network of third-party installers to install its products. Getting multiple quotes might lead you to a solar provider that offers discounts or lower labor costs in an effort to get your business.
Getting multiple quotes can be time-consuming and involves being home for a few different in-person home inspections. However, it is often worthwhile and could save you hundreds or even thousands of dollars on your solar panel system.
Enter your zip code below to get connected with the top-rated installers in your area.
SunPower is the clear industry leader in solar technology and panel efficiency rating, but it also provides the best solar panel warranty coverage available for homeowners. SunPower’s warranty covers the equipment, including manufacturing defects, as well as the panel efficiency and a below-average rate of degradation.
SunPower’s product warranty covers manufacturer defects for 40 years, which is 1.6x the industry average of 25 years. SunPower also has a great reputation for responding to warranty claims.
The company also guarantees the panel efficiency for 40 years, which is also 1.6x as long as the industry average of 25 years. Most other panel performance warranties guarantee that between 85% and 90% of the starting efficiency will remain after the 25-year warranty term. SunPower guarantees that 92% will remain after that same term, which is the best in the industry and only matched by a few other manufacturers.
The expected lifespan of SunPower panels is a minimum of 40 years, but many solar customers are likely to find that their panels continue producing sufficient energy after that point.
SunPower only sells its panels through its in-house installers and its certified third-party installers. They aren’t available for purchase for DIY solar panel installations. You can follow the steps below to get a SunPower system installed on your home:
SunPower has a large network of installers that is split into three categories: SunPower Authorized Dealers, SunPower Elite Dealers and SunPower Master Dealers.
There are hundreds of SunPower Authorized Dealers located throughout the country, with representation in all 50 states. Authorized Dealers are approved by SunPower to install its high-performance panels and go through special training to get authorization. These companies are also held to certain customer satisfaction and labor quality standards.
Elite Dealers complete advanced training programs through SunPower and meet even stricter standards when it comes to customer satisfaction and overall high-quality workmanship.
Master Dealers are hand-picked by SunPower to represent the brand. They uphold the highest standards set forth by the manufacturer.
As one of the biggest solar companies in the country, SunPower’s network of installers is unusually large. You can click the buttons below to get connected with approved installers in your area.
SunPower’s commitment to quality products is evident in the A+ rating with the Better Business Bureau (BBB) and in the customer reviews for the panels themselves. Most customers rave about the customer service, and specifically the attention they receive in response to warranty claims and issues post-installation. It’s obvious that customers trust the manufacturer and are pleased with the panel performance.
Conventional panel manufacturers that don’t have as rigorous of an installer selection process don’t get the same reviews, although most negative reviews stem from a lack of service from the installer and not the manufacturer. Few customers complain about panels themselves, to be fair.
The reviews we read through in which customers do mention the performance of their SunPower panels are overwhelmingly positive.
One complaint we often see about individual panel brands is less appealing performance and production than the customer expects. In many cases, this is the fault of the installer, as they are responsible for accurately representing expected production. Since SunPower manufactures the most efficient solar panels, and because the company vets its installation network, this is a rare occurrence among homeowners who get SunPower panels installed.
Most customers mention that they’re pleased with the production. We also see comments about warranty coverage and the company’s willingness to fix issues if they do arise. Again, this is not always a reflection on SunPower panels alone but also on the installers with which the company works.
Overall, most solar customers seem to be pleased with SunPower panels and dealers, which is really saying something, given the company’s size.
Thankfully, there are relatively few negative comments about SunPower panels other than the fact that they’re quite expensive.
There are some instances in which homeowners don’t get the quality of service they expected, but these complaints are directed toward the installers and not the actual products. Still, it does suggest that SunPower isn’t always able to ensure its many authorized dealers uphold its in-house commitment to service. Your experience can vary based on where you live and which installer you choose.
This kind of complaint is very common among different manufacturers, so we don’t believe it’s indicative of an issue specifically with SunPower.
Overall, we believe SunPower is the number one panel manufacturer in the industry. It uses cutting-edge technology to maximize panel production and efficiency and minimize degradation. Ultimately, this helps customers reach greater energy savings and allows them to install fewer panels on their homes, which is great news if you have limited roof space.
The table below includes some key specifications for SunPower panels as compared to panels from other manufacturers. This should help illustrate why SunPower is so highly rated and why we think it’s the best option overall.
|Max Efficiency Rating||22.8%||22.3%||20.6%||22.2%||21.4%|
|Degradation Per Year (After 1st Year)||0.25%||0.5%||0.5%||0.26%||0.5%|
|Equipment Warranty Term||40 years||25 years||25 years||25 years||25 years|
|Efficiency Warranty Term||40 years||25 years||25 years||25 years||25 years|
|Average Price Per Watt||$3.30||$3.00||$2.90||$3.10||$3.00|
|Panel Manufacturer Review||–||Read Our REC Panel Review||Read Our Tesla Panel Review||–||Read Our Silfab Panel Review|
Yes, absolutely. Overall, SunPower is the number one panel brand we recommend, and it’s the one we’d be most comfortable installing on our own homes. SunPower panels are the most efficient in the industry. They outperform most other brands in most areas, come with an industry-leading warranty and have one of the best reputations for quality and value available.
SunPower panels are more expensive than most other options, but we strongly believe the quality and high efficiency will lead to a lifetime of higher energy savings that will more than pay for the increased price you’ll pay. We suggest using the buttons below to get estimates from multiple SunPower installers to get the best upfront price possible.
When we review any solar manufacturer, we look at 18 different criteria across seven categories to ensure we only recommend the best products available. We’ll briefly explain what we looked at when reviewing SunPower below.
Below, we’ll answer some of the most common questions we see from customers about SunPower panels.
Yes! SunPower panels are widely considered the best in the industry. They have above-average efficiency ratings, greater durability and lengthier warranty coverage. They are expensive, but we believe they’re well worth the high cost.
SunPower is one of the few solar companies that advertises its panel failure rate, and it’s extremely low. The company claims that only 1 in 20,000 panels will fail. Even if a SunPower panel does fail, the company’s 40-year warranty is likely to cover the replacement.
SunPower used to manufacture its own panels and outsource the installation to third-party companies. Its sister company, Maxeon, now handles manufacturing, and SunPower exclusively installs Maxeon panels.
SunPower panels are warrantied for an incredible 40 years for manufacturer defects and power production. The panels are expected to last at least that long, but they can and do last longer in many cases.