Results of a series of tests designed by the National Renewable Energy Laboratory (NREL) and conducted by PV Evolution Labs (PVEL) to measure the performance of various inverter technologies in various shading conditions were published. The test determined the annual percentage of energy recovered by power optimizers and micro inverters when compared to traditional string inverter systems in shaded conditions. The results indicate that the SolarEdge optimized system generates 2%, 5% and over 8% more energy than traditional string inverters in light, medium and heavy shading scenarios, respectively. The SolarEdge system outperformed all systems in annual energy production demonstrating higher results than the leading micro inverter solution as well.
"The SolarEdge system yielded more energy than the string inverter system in all tests. On an annual average, the SolarEdge system recovered 24.8% of energy lost due to shading, while the microinverter system recovered 23.2%," says Matt Donovan, PV Evolution Labs.
SolarEdge power optimizers track Maximum Power Point (MPP) at the module-level and thus mitigate shading losses occurring with string or central MPP tracking. In addition, as opposed to micro inverters, power optimizers can track a module’s MPP at voltages as low as 5V, a specification allowing SolarEdge to optimize module performance even under severe shading conditions.
“The results of the NREL shading test further confirm what we have stated previously,” says Peter Mathews, VP of North America Sales & Marketing, “The SolarEdge system offers the highest performing module-level power management at a cost that is similar to other string level PV inverter solutions. Not only do we offer a higher level of shading protection, we also offer an efficiency gain over other module-level solutions.”