SunPower is a US-based manufacturer who currently holds the record for the most efficient solar panels in the industry (22.8% as of 2022).
The brand is very popular in the US, and you have probably seen it already if you’re considering solar panels for your home. SunPower is considered the most premium solar panel brand, where you pay above-average prices but also get superior performance and durability.
The installed average cost of a home solar system in the US is around $3.06 per watt, according to the Solar Energy Industries Association (SEIA).
When using SunPower panels, you can expect to pay around $3.35 per watt, according to system pricing data gathered by EnergySage. However, you will get the most efficient solar panels in the industry for that extra investment: SunPower reaches 22.8% efficiency, followed by LG (22.3%) and REC (21.9%).
SunPower is an excellent option when you have limited space for solar panels, since they convert a higher percentage of sunlight into electricity. This means they will save you more dollars per square foot covered, compared with less efficient panels.
SunPower Solar Panels: What Product Lines Are Available?
SunPower solar panels come in four product lines, each with its own specifications. The following table summarizes their main features:
|SunPower Product Line
|Up to 22.8%
|390 – 420W
|Up to 22.8%
|Up to 370W
|Up to 20%
|320, 327, or 435W
|Up to 19%
|380 – 400W
The A-Series, X-Series and E-Series all use the Maxeon monocrystalline solar cell technology, which was developed by SunPower. The P-Series uses a shingled solar cell design that is also from SunPower, and they are optimized for larger commercial systems.
SunPower not only offers photovoltaic panels, but also complete solar systems with inverters and energy storage, along with the installation service. This gives you the advantage of dealing with a single manufacturer, instead of using components from different brands.
Did you know? SunPower also offers better warranty conditions when you purchase a complete solar power system.
In case you’re planning a roof replacement, SunPower has a roofing system called OneRoof, which is designed for easy integration with their solar panels. Their OneRoof system is UL certified and it has a Class A fire rating.
The size of SunPower panels varies depending on the specific product you pick, and keep in mind that commercial modules are larger. Here are the dimensions of some of their most popular solar panels:
- SunPower E-Series E20-327 = 61.3” x 41.2”
- SunPower X-Series X22-370 / X22-360 = 61.3” x 41.2”
- SunPower A-Series: A420 / A415 / A410 / A400 / A390 = 72.2” x 40”
SunPower manufactures both monocrystalline and polycrystalline modules. However, their most efficient products use monocrystalline Maxeon cells, as you might expect.
Overview of the SunPower Solar Panel Warranty
SunPower not only offers superior efficiency, but also some of the best warranty terms in the industry. The brand gives you a 25-year warranty that covers both defective products and loss of performance over time. In case you purchase your entire PV system from SunPower, the warranty will also cover labor and other components.
- The performance warranty from SunPower offers you 92% DC output after 25 years, which means their solar panels remain productive for a very long time.
- For comparison, some low-end solar panels are only rated for 80% performance after 25 years of use.
- Even if their power output warranty has the same duration, the electricity delivered over time is much less, and this also means your power bill savings are reduced.
Having a reliable warranty with a long coverage period is very important when purchasing solar panels, since it protects your investment.
Many homeowners decide to install solar panels due to the savings achieved over time, and a warranty ensures these savings will reach your pocket. On the other hand, a low-quality solar system without warranties may fail in just a few years or months before you can recover your investment.
Even if a solar manufacturer offers a warranty with excellent conditions, be aware that an unprofessional installation may void that warranty. SunPower offers you the option of purchasing the entire solar system, not only the panels, which means you can combine all component warranties.
- Normally, when you need to file a warranty claim, you must prove that the fault was not caused by other components of the solar power system.
- However, this hassle is avoided when the same brand responds for all components.
Are SunPower Solar Panels Suitable for Hot Climates?
To find out how a solar panel brand performs under the heat, you can look at its temperature coefficient. This may sound like a very technical term, but the concept is simple:
- The temperature coefficient is the productivity loss suffered by a solar panel, for each Celsius degree of temperature rise.
- Keep in mind that the capacity lost with temperature does not represent permanent damage for solar panels. Once they cool down, they regain that generation capacity.
Depending on the specific product, the temperature coefficient offered by SunPower ranges from -0.38% to -0.29% per °C. There are few solar manufacturers who have achieved temperature coefficients below -0.30% per °C, and SunPower is part of that list.
However, keep in mind that this coefficient varies from product to product. If you plan to use SunPower panels in a place with very hot weather, you should ideally use a solar panel model with a temperature coefficient of -0.29% / °C. With this temperature coefficient, a temperature rise of 25°C will only reduce the electricity output by 7.25%.
On the other hand, if you pick a SunPower panel with a coefficient of -0.38% / °C, there is a 9.5% loss with the same temperature rise. The difference may seem small, but it adds up when solar panels are constantly operating in a high ambient temperature.
What Are Some Alternatives for SunPower Solar Panels?
SunPower is considered a premium solar panel brand, but there are other manufacturers who offer products with comparable specifications. Here we will compare SunPower with other top-tier solar brands.
If you’re looking for high efficiency solar panels, SunPower is the industry leader. However, the following brands also offer superior efficiency, and there is only a small difference between them and SunPower:
- LG Solar: Up to 22.0% efficiency
- REC: Up to 21.7% efficiency
- Panasonic: Up to 21.2% efficiency
Solar panels with high efficiency produce more kilowatt-hours during their service life, and they also make each square foot of roof space more productive. However, there is a common misconception that lower efficiency means lower quality, but that is not the case.
You can find excellent solar panels with efficiency ratings below 20%, and they often have a lower cost per watt than high-efficiency modules. Unless your roof space is very limited, solar panel efficiency is not a critical factor.
In case you’re looking for solar panels with a long product warranty, there are many other brands that offer 25-year coverage. LG Solar, REC and Panasonic are also part of this list, along with brands like Silfab, Solaria and Q Cells. The warranty period varies depending on the solar panel brand and model, but you should look for at least a 10-year coverage, since this protects your return on investment.
Finally, if you’re looking for brands with good performance at high temperature, Panasonic and REC offer temperature coefficients up to -0.26% per °C. They’re slightly ahead of SunPower in terms of hot weather performance.
Regardless of the solar panel brand you pick, we strongly recommend you get a professional installation. Even the best solar panels will give trouble if they are not installed and wired properly, and you could end up losing the warranty.
To summarize, SunPower is a premium brand that focuses on high efficiency and long-term warranty coverage. As you might expect, these benefits come with a higher price tag: while many solar brands have installed costs below $3 per watt, SunPower has an average cost of $3.35 per watt according to EnergySage data.
Depending on what incentives are available in your area, the net price of a SunPower solar panel system can be less. Regardless of where you live in the US, you will get 26% of your investment back as a federal tax credit when you file your next declaration.
When this financial incentive is considered, the average cost of SunPower panels drops to around $2.50 per watt. If your local government or power company offers additional incentives, you can achieve an even lower net price.
Keep in mind that not all SunPower solar panels have 22.8% rated efficiency, and they also have value products with lower efficiency ratings and prices. However, they are also high-quality solar panels covered by a 25-year warranty. SunPower also offers complete home solar systems along with installation services, which are a good option if you prefer not to deal with several brands.
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