Calculating PV Degradation Rates Using Open-Source Software

Got sensor drift, inverter clipping or data shifts due to maintenance events? RdTools, a new freeware toolkit, can handle any of these scenarios. It calculates robust degradation rates despite common performance data quality challenges. The degradation rate (Rd) quantifies the rate at which PV systems or modules lose performance over time. Rd values not only drive the results of long-term energy production estimates for financial projections and other studies, but also help provide consumers and investors with an indicator of PV system quality and durability. In conjunction with taking other quality assurance steps, project stakeholders can also use the Rd to guide product selection and determine whether PV products or installations meet warranty terms. Accurate Rd data are therefore essential to the solar industry's long-term success. Here we provide an introduction to RdTools, a free and publicly available software package intended to help users evaluate Rd more easily and quickly. One of the benefits of this open-source toolkit for calculating degradation rates is that it can accommodate common challenges associated with real-world performance data, including sensor drift, clipped power curves or data shifts due to maintenance events. Since accurate methods for calculating PV degradation rates are important for manufacturers, insurers, engineers, utilities, installers, investors, businesses and consumers alike, many solar industry stakeholders may find RdTools useful.