SunPower solar panels review

SunPower solar panels: the complete review

SunPower solar panels are one of the most frequently requested solar panel brands on the EnergySage Solar Marketplace, and for good reason. SunPower panels are often the most efficient (read: powerful!) products on the market today, and they offer an industry-leading warranty. For many years, SunPower has been a fully-integrated solar shop: manufacturing solar cells & panels, and then offering sales and installation services for residential and commercial applications as well. While they are considered some of the best panels, they come at a premium price.  In 2019, SunPower announced that they’re spinning off their manufacturing arm into a new company–Maxeon–to focus on installing solar panels.

This is an unbiased review: EnergySage is not paid to review brands or products, nor do we earn money from affiliate advertising in this article. The content of this blog is based on research and information available at the time of writing. Learn more about our mission and how we make money as a company.

Key takeaways

  • SunPower panels are manufactured by Maxeon.
  • SunPower’s solar panels range in efficiency from 20.1% to 22.8%, and they have a materials warranty lasting for 25 years.
  • SunPower solar panels cost between $3.12 and $3.74/W on the EnergySage Marketplace – that’s $18,720 to $22,440 for a 6 kW system, before the federal solar tax credit.
  • Shop for SunPower solar panels (and many other brands!) today on the EnergySage Marketplace.

What’s in this article?

How much do SunPower solar panels cost?

This means that, for a 6 kW system, your gross cost would be anywhere from $18,720 to $22,440. However, remember that most homeowners end up paying much less than the total gross cost. There are plenty of solar incentives and rebates to help you reduce upfront costs, including the 26 percent federal tax credit for solar.

Our SunPower reviews wouldn’t be complete without a discussion of how much SunPower solar panels cost. As you might expect, if you want to invest in the highest-quality solar panels available, you’ll end up paying a higher sticker price as a result.

However, the price of SunPower solar panels might not be as high as you think. We reviewed quotes offered on the EnergySage Solar Marketplace that included SunPower solar panels and found that these systems were priced between $3.12/Watt and $3.74/Watt. By comparison, the average price on the Marketplace during the same time period was $2.77/W – SunPower systems were pricier, but not by an astronomical amount.

How SunPower X-Series, E-Series, and A-Series solar panels compare to other panel manufacturers

As you evaluate overall solar panel quality, there are four key metrics that you should consider: efficiency, performance, warranties, and price. To help you with your decision, EnergySage has developed SunPower reviews for each metric, along with a comparison of SunPower solar panels (including the esteemed SunPower X-Series) against the other leading panel manufacturers offered on the EnergySage Marketplace.

Note: SunPower doesn’t manufacture their own solar panels. While the information included in this article refers to their panels manufactured by Maxeon, due to supply chain constraints SunPower has recently been offering solar panels by other manufacturers, which can differ in quality. So, be sure to double check which solar panels you’re receiving if you choose to go with SunPower!

How SunPower panels compare to other manufacturers


Temperature coefficient

SunPower X-Series Residential AC SPR-X22-360-E-AC

25 years

PMax: -0.29
Panasonic EverVolt WBS EVPV370 WBS25 years

PMax: -0.26

Silfab Elite SIL-380

30 years

PMax: -0.377

REC Alpha REC400AA Pure Black

25 years

PMax: -0.26


25 yearsPMax: -0.34

How SunPower panels compare to one another

Panel seriesWatts Efficiency

470W22.7% efficiency



22.7% efficiency



25% efficiency


The term “solar panel efficiency” refers to how well a solar panel can convert sunshine into useful electricity. Given the same conditions, a high-efficiency solar panel can produce more electricity than a lower-efficiency panel of the same size. For this reason, a higher efficiency rating is generally preferable.

SunPower solar panels are the most efficient panels currently available on the market in the United States. While the majority of solar panels fall in the 14% to 18% efficiency range, SunPower’s products are much more efficient – between 20.1% and 22.8%. If efficiency is your top priority, the technical specifications of SunPower solar panels are unparalleled.

Performance (temperature coefficient): SunPower X-Series

For this portion of EnergySage’s SunPower reviews, we use the temperature coefficient as an indicator of panel performance. The temperature coefficient represents how well your solar panel can handle less-than-ideal conditions. Solar panels, like other electronics, perform their best when they are kept cool (ideally around 25° C/77° F). You can use the temperature coefficient to get a sense of how your panel’s performance will change during hot sunny summer days.

For every degree above 25° C (77° F), your solar panel’s electricity production will decrease by its temperature coefficient. For example, SunPower’s SPR-X21-345 panel has a temperature coefficient of -0.3%/°C. This means that, if the panel’s temperature increases by one degree from 25° C (77° F) to 26° C (79° F), its electricity production will be reduced by -0.3%. If its temperature increases all the way to 35° C (95° F), electricity production will decrease by 3%.

Ideally, you want the lowest temperature coefficient possible. SunPower’s solar panels offer some of the best temperature coefficient ratings on the market today, between -0.35 and -0.29.


Whether you’re buying a TV, a car, or solar panels, the manufacturer should stand behind their product with a strong warranty. A solar panel’s materials warranty (sometimes referred to as the product or equipment warranty) guarantees that it will be replaced in the event of equipment failure due to manufacturing defects or environmental issues.

Most solar panel manufacturers offer a 10-year materials warranty, but the best solar panels come with a 12, 15, or even 25-year warranty. In keeping with SunPower’s industry-leading position in the other metrics we’ve assessed, the company offers a 25-year warranty against any defects in their products.

Every solar panel’s production naturally degrades over time. The performance warranty is a manufacturer’s guarantee that your solar panels’ production won’t degrade too quickly. In addition to a leading materials warranty, SunPower offers one of the best performance warranties of any solar panel manufacturer we’ve reviewed. Most solar panel brands offer a performance warranty stating that their panels will still be producing at somewhere between 80% and 83% of their original capacity after 25 years. By comparison, SunPower’s performance warranty is 94% after 25 years – a full 9% to 12% higher than most other panel manufacturers offer.

Check out our in-depth review of SunPower’s warranty.

Frequently asked questions about Sunpower solar panels

Are SunPower solar panels any good?

In addition to their good prices, SunPower solar panels also have a best-in class warranty to give homeowners peace of mind.

What brand of solar panels does SunPower use?

Sunpower uses their own internal brand of panels called Maxeon.

Is SunPower a good solar company?

SunPower has a strong warranty, customer service, and products.

Who bought SunPower?

TotalEnergies SE purchased a controlling interest in SunPower for $1.37 billion in 2011.

What inverter does SunPower use?

SunPower uses microinverters. A microinverter converts the power from DC to AC for increased efficiency.

How to find the best price on SunPower solar panels 

SunPower panels are, without a doubt, some of the best solar panels available today. When EnergySage ranked the best solar panels on the market, our SunPower reviews were the highest of any panel brand. If you have a limited amount of space and need to maximize your solar panel system’s production, you can’t go wrong with an installation that includes SunPower solar panels. However, not every homeowner needs the most efficient panels available on the market. If you have enough space for a larger system, installing slightly less efficient panels may give you the performance you need at a slightly better price.

The best way to determine whether SunPower solar panels are the best solar panels for your home is to review multiple quotes with different solar equipment options before making a decision. When you compare all of your options on the EnergySage Marketplace, you’ll find the right combination of price and quality that meets your needs. When registering, simply note in your profile that you’re interested in receiving quotes that include SunPower solar panels for your home. Many of our qualified, pre-vetted solar installers are part of SunPower’s certified solar installer network, which means you can be confident that every aspect of your solar system installation meets the highest standards.

64 thoughts on “SunPower solar panels: the complete review

  1. Debra Morrison-Orton

    I purchased a house with Sun Power (SP) panels. I had significant damage on my roof related to the July GV storms and need roof repair. I need to have the panels removed to repair the roof. Since July our family has reached out to SP to come and remove the panels so this repair can occur. At least 40 calls later there has been either no response or we are given a # to agencies that claim they cannot do it. It is EXTREMELY POOR CUSTOMER SERVICE I would not recommend this company. Save your money and your sanity. It is now 24 Sept 2021 and no one has followed up.

    1. Guillermo De la vega

      Sounds like you need to call your insurance company, damage to your roof from a storm has no blame on solar panels.

    2. DannyMcO

      If you own the panels this problem is usually more easily mitigated – but it highlights the perils of leasing (that being no owning what’s on your own roof).

  2. Danno

    Wow, this is scarey to read. I had Sunpower installed and activated just 3 weeks ago, so far so good.
    My 9.45 KW system has been pumping out over 40KW each sunny day since, I sure hope it continues…

    1. Brian Rezac

      Danny, you are good to go. You bet on the worlds number 1 panel in efficiency and quality. If you went with any other panel, the statistical probability you’d habe a issue is higher. You’ll be just fine. You have Stanford University tech on your roof. Nothing is perfect, and you shouldn’t expect perfection, but the best panel money can buy is on your roof.

  3. Joesph Jones

    Just wanted to thank the many many individuals who took the time to relate their experiences with Sunpower. I have been investigating solar manufacturers and sellers as I plan to go solar this year.
    Thanks to the wonderful heads up I actually canceled a sales call with the local Sunpower sales rep.
    If there is one thing I’m not looking to purchase it’s more headaches.

    1. Georgia

      Great job! I think that was a great idea. I purchased these and the follow thru from Sun Power is TERRIBLE. I have had issue and have wasted hundreds of hours resetting my system and fighting with Sun Power to do the appropriate warranty work. You definitely saved yourself some headaches!

      1. PT

        Just checking, but are you based in the Philippines? I’m wondering if support/service varies largely based on country/region.

    2. Georgia

      Great to hear. I hope Sun Power starts to realize the way they do business DOES impact their business.


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