April 17, 2017 | by Brittany Good | Engineering + Technology, Solar Resource Measurement
Photovoltaic (PV) modules often collect more than sunlight after they are installed. Depending on the siting location, particles ranging from dust to snow can accumulate on a PV module’s surface, reducing its performance and ultimately leading to significant power losses. This build-up – commonly referred to as soiling – can be compounded by such weather parameters as wind speed, relative humidity, and ambient temperature, as well as localized activities near or around the PV plant.
To address and ideally avoid power losses caused by soiling, the new IEC 61724-1:2017 standard for PV system performance monitoring suggests that operators of utility-scale and large PV projects measure soiling ratio, which is defined as the ratio of the actual power/current output of a PV array under given soiling conditions to the power/current that would be expected if the PV array were clean and free of soiling. By measuring soiling ratio, operators are armed with the vital information needed to make practical decisions, like scheduling solar panel cleanings, that can better optimize the performance of their PV plant.
NRG Systems recently introduced a Soiling Measurement Kit specially designed to help PV developers and operators obtain the information needed to quantify the site-specific impacts of soiling on prospective and current PV projects. The turnkey solution is offered as an accessory to our Solar Resource Assessment System and comes with three PV modules (one for data logger power, one clean panel, and one dirty panel), pre-installed back-of-module temperature sensors, flexible mounting hardware, and an integrated soiling interface module.
The Soiling Measurement Kit connects with NRG Systems’ SymphoniePRO Data Logger and provides a wealth of raw soiling measurement data that can be used to determine soiling ratio. Specifically, the Kit measures short circuit current and back-of-module temperature with the user’s choice of statistical interval as well as optional 1 Hz sample data collection, providing flexible analysis options to meet data demands. Generally, solar module performance decreases with increasing temperature, so back-of-module temperature measurements provide the critical information needed to accurately predict a PV plant's power output.
Whether you are looking to improve annual energy production for your pre-construction PV projects or optimize panel washing schedules and forecasting model for existing arrays, Renewable NRG Systems’ Soiling Measurement Kit provides an effective and straightforward way to collect the data you need to produce more energy more of the time. For more information about our Soiling Measurement Kit, please contact our sales team at email@example.com.