December 20, 2024 | by Julia Ravelson | Engineering + Technology, Solar Resource Measurement
Calibrating solar instruments used in your solar resource measurement campaigns is critical to minimizing measurement uncertainty, ensuring data integrity, and maintaining compliance with IEC, ISO, and WMO standards. In the final installment of our blog series highlighting the critical role of meteorological data in building and operating successful utility-scale solar projects, we explore the importance of instrument calibration and how NRG Systems is uniquely equipped to support this endeavor.
Understanding the Calibration Process
Instrument calibration occurs at two key points during a solar resource measurement campaign:
- Pre-Deployment Calibration: Conducted as a final step in the manufacturing process, this ensures precise, high-quality data from the outset of a measurement campaign.
- Post-Deployment Recalibration: Performed after two years of data collection, this addresses potential sensor drift to maintain measurement integrity.
The Role of Instrument Calibration in Measurement Success
According to IEC 61724-1:2021, Class A pyranometers must have calibration uncertainties of less than or equal to 2% at 1000 W/m^2. This specification sets a stringent margin of error, ensuring the sensor deviates by no more than 2% from the true measured value after calibration. Low calibration uncertainty indicates that the pyranometer is highly accurate and reliable, enabling high-quality data collection critical for solar resource assessment, energy yield predictions, and performance monitoring.
Over time, pyranometers may experience shifts in their response to incoming radiation due to degradation, environmental factors, or sensitivity drifts. Recalibrating these sensors periodically accounts for these accuracy drifts, ensuring long-term datasets remain consistent and reliable for performance assessments and predictions.
How NRG Supports Efficient and Effective Calibrations
Every pyranometer purchased through NRG Systems – whether our own R2 Pyranometer or sensors from our portfolio of trusted third-party instruments – includes a calibration certificate traceable to the world standard and sensor-specific data. R2 calibration reports are easily accessible via the Calibration Report Retriever tool on the NRG website.
When your fielded instruments are due for calibration, NRG Systems streamlines the process to minimize downtime and avoid data interruptions. Our expert Technical Services team supports you at every step, starting with coordinating your sensor shipment to NRG for diagnosis. From there, we facilitate calibration at an ISO-accredited facility. After calibration, we manage the safe return of your sensors, perform a post-calibration check and ship securely to the desired location. This comprehensive approach ensures your sensors are field-ready with optimal performance and accuracy.
Maximizing Project Success Through Calibration
Following pre- and post-deployment calibration protocols is essential for conducting accurate solar resource assessment campaigns and ensuring reliable long-term solar resource monitoring. By adhering to international standards like IEC 61724-1:2021 and leveraging NRG Systems’ end-to-end calibration services, you can minimize measurement uncertainty, maintain data integrity, and maximize the long-term value of your solar projects. Trust NRG Systems to keep your solar instruments performing at their best – because precise measurements drive better decisions.
For more information about NRG’s solar solutions, including our calibration processes and services, contact sales@nrgsystems.com. Be sure to read the previous installments of this blog series HERE.
