PVEL Scorecard Gives Out Top Marks for Solar Modules
On May 28th the 2020 PVEL scorecard was released. This annual listing is an incredibly helpful resource for solar professionals everywhere whether you’re just getting into solar or have been installing for years. In this article, we’re breaking down the 2020 scorecard results and what it means for the solar industry in 2020 and the future.
Who is PVEL?
PV Evolution Labs (PVEL), located in Berkeley CA, is an independent testing lab that strives to provide PV consumers with reliable data in order to accelerate the adoption of solar power. Starting in 2010 PVEL has been working to increase confidence in the dependability of solar modules by providing a comprehensive data source for consumers. Through their reliability and performance tests, PVEL creates a yearly Scorecard that they have been releasing since 2014.
What is the PV Module Reliability Scorecard?
The Scorecard provides readers with a list of manufacturers who are the top performers that year along with any previous year that those manufacturers were a top performer. The list is ordered based on how many years they have been selected as a top performer and then by alphabetical order. Previous years Scorecards are available on the PVEL website.
The 2020 Scorecard was created through the results of five tests PVEL runs along with a factory level audit of manufacturers plants. The tests include Thermal Cycling, Damp Heat, Dynamic Mechanical Load Sequence, Potential-Induced Degradation (PID), and a PAN test. Each test was designed to simulate different conditions that could affect the quality of the module under certain conditions or the performance of the modules.
The Thermal Cycling test is designed to challenge the reliability of modules during changes in temperature. The test involves the modules being exposed to extreme temperature changes rapidly. This test was created to discover how modules react to changing temperatures and if they are likely to be damaged or decrease performance. Modules that are deemed top performers have a power degradation of 2% or less. However, most modules that have passed historically do much better, with a median degradation of only .67%.
The Damp Heat test’s goal is to determine the reliability of modules under high heat and humidity conditions. The test puts modules in a testing area where they are exposed to high levels of heat and humidity for about 84 days. This test is valuable as these weather conditions can cause the adhesives that bond PV module components together to weaken; this causes lower module performance due to foreign elements, like dirt or soil, entering the module. For a module to be considered high performing it must suffer less than a 2% degradation in power.
The Dynamic Mechanical Load Sequence is “one of the most rigorous test sequences”. The test is designed to mimic the different stresses that modules face during heavy wind or snow conditions. The test proves that modules can withstand the adverse weather conditions that many areas of the country face. Top-performing modules are those that only suffered a 2% degradation or less in power performance. During the test, modules are subject to large pressure increases, along with shorter versions of the thermal cycling and damp heat tests.
The PID test was born out of recent developments in module manufacturing, where higher voltage and ungrounded systems have become more common. Potential-induced degradation can occur when sodium ions from the glass in the modules react with the silicon coating; this reaction can lead to underperformance of the module and can cause permanent damage. The test puts modules at their full voltage and certain environmental conditions, which allows PVEL to detect leaks that occur in the cells. These leaks lead to sodium ions interacting with the coating and underperformance in the modules. Like the other tests, all top-performing modules had a degradation of 2% or less in their performance. A note from the report mentions that while many of the modules tested were top performers, the median level of degradation was the highest PVEL ever recorded.
The final test conducted by PVEL is PAN. PAN is the file type that PV modeling software uses to show the “irradiance- and temperature-dependent behavior of a PV module”. Essentially the PAN files model the energy yields of a module based on irradiance and temperature. PVEL created an experiment where they use each manufacturer's PAN specifications, for each module, and apply them to the same environment. The top performers are those who have the highest energy yield.
What are the 2020 scorecard trends?
The historical data PVEL provides shows that module efficiency has increased over time and that only 4% of previous scorecard top performers would have qualified in 2020. Overall, PVEL designated 22 manufacturers as top performers for the year 2020. Some of these top performers include Jinko Solar, Q-CELLS and Panasonic. Three of the top 22 manufacturers were first time top performers. Out of the 22 top performers, five had factories that were based in the US.
PVEL also highlights three top trends in solar module production:
- PERC cells have replaced Al-BSF cells
- Manufacturers have improved cell design to increase efficiency and lower costs
- Modules are being redesigned to be lighter, through thinner frames and lighter-weight materials.
As PV systems continue to be adopted by more households it’s important to provide yourself with the right information to make the best decision for your PV projects. If you want to talk with one of our CED Greentech experts about selecting the best solar panels for your projects, call your local rep or contact us today.