By Sarah Lozanova, Solar Marketing Professional
Technological advances continue to transform the solar energy industry. Today’s solar panels are significantly more efficient, producing more power in the same amount of space. Meanwhile, prices have fallen, reducing the cost of solar electricity.
But are some solar panels a better choice for homeowners? Which models and manufacturers are the most reliable and durable? Do some models create less pollution in the manufacturing process? Do panel manufacturers use recycled components or provide solar panel recycling options at the end of life? Let’s explore these critical issues in the pursuit of the best solar panels on the market.
We compared the efficiency, warranty, environmental performance, and more for the following solar panel models in the comparison chart below. Because LG Electronics recently announced it would exit solar panel manufacturing, its products are not included.
Solar Energy Is a Dynamic Industry
Despite the pandemic, the solar energy industry has been quite resilient. However, factory closures, tariffs, raw material shortages, and shipping bottlenecks sometimes create supply chain shortages and delays.
Because solar panel technology continues to advance and evolve, the market is very dynamic. Manufacturers release new products as older models become obsolete. The cost of advanced solar batteries has been dropping as demand has surged. The most efficient solar panels on the market today will probably not seem so advanced in a decade as the technology matures.
Solar Panel Considerations
Solar panel efficiency relates to how much available sunlight is converted into solar electricity. And the more efficient a solar panel is, the more electricity it generates in a given space.
Thanks to technological advances, solar panels have become significantly more efficient in recent years. Solar panel efficiency becomes more critical when there are space constraints due to the size of your roof or property.
Unfortunately, more efficient solar modules typically cost more. For installations with limited space, panel efficiency is an essential consideration. If space isn’t an issue, efficiency is less crucial.
Long-Term Power Generation
Like most other technological devices, solar panels degrade over time. They become less efficient in turning sunlight into electricity. The degree to which they degrade is significant because solar panels can last 30 years or more. Ideally, your solar system will still be generating plenty of energy a few decades from now, even if someone else owns the house.
Solar panel manufacturers offer a power production guarantee to ensure a particular output level over a given time. For example, many solar panel manufacturers guarantee 90% production for 10 years and 80% for 25 years.
Some manufacturers differentiate themselves by offering more robust warranties. For example, SunPower leads the industry by providing a 25-year performance guarantee of 92% or higher, depending on the model. The higher the value of the 25-year production warranty, the more power the panels will likely generate 25 years down the road.
Solar panel warranties cover defects and failures, helping to protect your investment. Warranties vary a lot by the manufacturer, and this often corresponds to the price range of the solar panel.
For example, SunPower and Silfab offer a 25-year product warranty, whereas Jinko and Ja Solar offer just a 10- or 12-year warranty. Of course, the longer the warranty, the lower the investment risk. But, in many cases, a more extended product warranty means higher solar panel prices.
Product warranties cover defects and failures, helping to protect your investment. Solar panel warranties vary a lot by the manufacturer, and this often corresponds with the price range of the solar panel. For example, SunPower and Silfab offer a 25-year product warranty, whereas Trina and Jinko offer just a 10-year warranty. The longer the warranty, the lower the investment risk. But in many cases, a more extended product warranty means higher solar panel prices.
Also, just because the manufacturer offers a long product warranty doesn’t mean your solar installer will provide an equally long labor warranty. That means that it might be necessary to pay an installer to replace defective panels — even if the manufacturer’s warranty covers the equipment.
The Silicon Valley Toxics Coalition (SVTC) is dedicated to a safe and sustainable solar photovoltaic (PV) industry. They produce a solar scorecard (the most recent is from 2018-2019) that rates manufacturers on extended producer responsibility, supply chain, workers rights, emissions reporting, module toxicity, greenhouse gas emissions, conflict minerals, and water use. The companies with the highest ratings are the most sustainable.
Some of these manufacturers have made additional strides in sustainability. SunPower is the first to earn Cradle-to-Cradle certification for its E-series and X-series DC solar panels. In addition, First Solar is a leader in solar panel recycling and is the only manufacturer that is a Preferred Recycling Partner of the Solar Energy Industries Association (SEIA) National PV Recycling Program.
Solar Panel Reliability Testing
PV Evolution Labs (PVEL) tests solar panels for reliability and performance measurements. Solar panel performance has a significant impact on the solar electricity of an array over time. Such testing helps ensure high-quality panels, reducing financial risk. PVEL produces a list of top-performing PV panels, and all the products on our list are top performers.
Most solar panels are manufactured in Asia, Europe, or North America. Modules made in the United States tend to be more expensive, but some solar shoppers want to support domestic manufacturing. Many companies produce panels in two or three countries. For example, Hanwha produces products in the United States, Malaysia, South Korea, and China. In 2019, they also opened a facility in Georgia that is the largest solar panel manufacturing plant in the Western Hemisphere.
Keep in mind that the manufacturing location and the company’s headquarters are not necessarily the same. Also, the manufacturing location isn’t necessarily an indication of quality. However, panels manufactured closer to the installation site might have lower emissions related to the product’s transportation, and the country of origin can have an impact on the worker conditions.
Solar Panel Aesthetics
Although traditional PV panels have a white backsheet and a silver frame, all-black modules have a black backsheet and frame. As a result, these panels have a sleek appearance and can blend in well with a dark-colored roof. Although they are relatively new, most major solar panel manufacturers offer all-black modules, but they sometimes have lower efficiency.
More Articles By Sarah Lozanova, Solar Energy Writer:
How Much Does a Home Solar System Cost?
How to Make Solar Farms More Sustainable
The Complete Guide to Solar Panel Recycling
What is a Microgrid?
Sarah Lozanova is a renewable energy copywriter and solar marketing specialist that uses digital marketing campaigns to drive results. She has an ability to gain media attention, boost website traffic, and engage interest on social media platforms. Lozanova connects solar energy companies to their target markets, by raising visibility, then hooking and engaging readers to request more information or take next steps.
Her renewable energy writer experience includes residential and commercial solar energy, battery energy storage systems, electric vehicles, and utility-scale wind energy, and she is the author of Humane Home: Easy Steps for Sustainable & Green Living. Sarah Lozanova holds an MBA in sustainable management from Presidio Graduate School and resides in Midcoast Maine.