Update: Unfortunately, LG has decided to stop manufacturing solar panels. Watch the video below for a recap of what this means for the solar industry and for a list of brands that will help fill the void left by LG's exit.
If you’re thinking about making the investment in a solar system, you’re going to want the best equipment you can get, price considered. Which brand of solar panels you choose can affect everything from how long the panels are warrantied to how much electricity they produce.
That’s why we want to take a deep dive into two of the industry’s top solar panel manufacturers: SunPower and LG. After reading this, we hope you’ll come away with what you need to know to pick the brand that’s best for you.
We’ll compare panels from each brand based on the following criteria:
It’s a cliche, but it still rings true: you really do get what you pay for. There are a variety of factors that come into play when determining the price of a solar panel. The type of panel, the size of the panel, and the brand of the panel – these are all factors that determine how much you should expect to pay.
An easy way to compare prices is to look at how much a solar panel costs per watt. While some brands have a lower price per watt, they likely won’t offer the efficiency and wattage of a more expensive brand.
When it comes to SunPower and LG solar panels, both brands are at the upper end of the quality spectrum. While this means you’ll be getting efficient panels backed by robust warranties, they likely won’t be the least expensive of your options.
On average, LG panels typically come in less per watt than SunPower’s panels.
SunPower panels typically are more expensive than LG’s panels.
Overall, LG typically offers a better price than SunPower. At about a $0.10 or more per watt difference, this can add up quickly, even on a smaller residential system.
The amount of electricity your solar panels can produce will determine everything from how many panels you need to the payback of your system. We’ll look at a panel’s production based on two factors: efficiency and wattage.
Solar panel efficiency is how much energy the solar panel generates compared to how much energy it takes in from the sun. The more efficient your panels, the more electricity you’ll be able to produce. LG and SunPower offer options ranging from mid-tier efficiency to high-efficiency panels.
The wattage rating is how many watt-hours the panel will produce in one hour of full sunshine. These numbers are the result of lab tests, so it’s not likely your panel will produce exactly that amount of power all the time.
LG’s most efficient panel is in their LG NeON line and features an efficiency of 21.7%, while their least efficient panel currently on the market is 19.6%. Their wattage rating ranges from 405W to 335W.
SunPower’s X-Series offers solar panels with efficiencies of up to 22.7%. On the lowest end of the spectrum is the P-Series, which includes solar panels with efficiencies of up to 19%. The SunPower X-Series top out at 470W for commercial use only.
Their A-Series offers the highest wattage for residential systems with a 400W option. Their E-Series offers a lower watt option of 300W.
Determining which brand has more efficient panels or panels with a higher wattage depends on the specific models you go with. While SunPower has the most powerful combination of efficiency and wattage, that may not necessarily be the best option for your project.
More power comes with a bigger price tag. Sometimes that additional power is needed because of limited space on your site, or allows you to produce more energy and offset more electricity, but which option is best for you really depends on your situation.
All reputable solar module manufacturers back their products up with warranties. Most solar panels are guaranteed for 20 to 25 years.
In order to be eligible for the manufacturer’s product warranty, your panels need to be installed per their specs. This is one of the many reasons it’s important to be discerning when choosing who will install your system and how. While a DIY installation may seem like a good way to keep costs down, you really run the risk of voiding your equipment’s warranty. That’s why it’s essential to partner with a reputable solar company.
Another important thing to consider when comparing equipment warranties is the dependability and stability of the company itself. If your solar panel manufacturer closes its doors, they won’t be around to fulfill your warranty request.
LG offers a 25-year product warranty. Founded in 1958, LG Electronics has been around for decades, producing everything from dishwashers to televisions. This global company not only has plenty of staying power, but it also backs up its warranties with an insurance policy. That means LG has the capacity to stand behind its warranties even now that they have exited the solar panel segment of its business.
Like LG, SunPower also offers a 25-year warranty. However, SunPower is a younger company that specializes only in solar. In November of 2019, SunPower announced its plans to separate into two independent companies – SunPower and Maxeon Solar Technologies. SunPower will continue as a solar installer, and Maxeon will take over the solar panel manufacturing. This change introduces a bit more uncertainty relating to manufacturing warranties.
While both LG and SunPower offer 25-year warranties, LG comes out on top in our book. With solar panel warranties backed LG Electronics, you can rest assured they’ll be able to fulfill warranties decades down the road.
Solar panel degradation is a process all solar panels go through. It’s the slow decline in your solar panel’s efficiency over time. The slower the degradation rate of your panels, the more electricity they’ll produce for you.
While degradation may sound bad, solar panel manufacturers offer protection against excessive degradation through warranties. The manufacturer will make things right if your panels degrade more quickly than they should.
LG will guarantee that some of their panels (depending on the model you select) will degrade no more than 10% in 25 years, meaning they’ll be at least 90% efficient after 25 years.
SunPower’s degradation or performance warranty is 92% after 25 years. That means that over 25 years, your panels will only degrade 8%.
LG and SunPower offer lower degradation rates than most other solar panel manufacturers. However, SunPower comes out on top in this arena with an 8% power decline to LG’s 10%.
To put it simply, SunPower is often the leader in efficiency, power output, and degradation rates. However, LG offers you almost all the high-quality, high-efficiency options SunPower does, but at a lower cost.
When it comes to warranties and degradation, SunPower offers the lowest 25-year degradation rate, meaning your panels will produce more electricity for a longer time. However, as a diversified global tech giant, LG’s warranties are backed by an extremely stable business that isn’t going anywhere.
While SunPower offers the most efficient panels on the market today, they charge a premium for that technology. LG, on the other hand, stands toe-to-toe with SunPower’s technology while still maintaining a lower price per watt.
View our other solar panel manufacturer comparisons:
*We accessed these specs on each company’s website in November 2019. To find out more about each company’s offerings, visit LG’s website here or SunPower’s website here.