Investigation of More Than 100,000 Months of Inverter Power Conversion Efficiency Data Using the Power Factors Database

Inverters are a key component of solar energy production, but most solar developers do not require independent verification of inverter performance. Module performance is often verified by independent test labs, but inverter specifications are accepted with no additional testing. In this report more than 100,000 inverter months of data were characterized to determine typical field inverter power conversion efficiency. Results indicate that most inverters perform within specification and newer inverter models with higher specifications do perform better. Additionally, performance degradation as a function of time in the field was not observed. That said, outliers still exist, and this benchmark can serve as a tool to identify low performing inverter models.