Fraunhofer ISE and PTB Ensure Precision in Photovoltaic Module Measurements Through Rigorous Comparison

In a collaborative effort to maintain the high standards of precision in photovoltaic (PV) module measurements, Fraunhofer Institute for Solar Energy Systems ISE’s CalLab PV Modules and Germany’s National Metrology Institute (Physikalisch-Technische Bundesanstalt, PTB) engage in regular comparisons of their independent output measurements. This meticulous process serves as a crucial reference for PV module manufacturers and developers of PV power plants, ensuring the quality of modules and providing accurate yield forecasts.

The recent comparison between CalLab PV Modules and PTB yielded remarkable results, with the measured outputs (Pmpp) deviating by less than half a percent from each other. This underscores the consistent accuracy of their calibration standards, instilling confidence in stakeholders within the PV industry.

Martin Kaiser, head of CalLab PV Modules at Fraunhofer ISE, emphasized the significance of these comparisons in maintaining a stable calibration standard. He highlighted the transparency provided to project partners, fostering trust in the reliability of CalLab PV Modules, a calibration standard upheld since 2008.

Dr. Stefan Riechelmann, head of the working group Solar Modules at PTB, reaffirmed their commitment as a national metrology institute to collaborate with calibration laboratories for the benefit of solar market stakeholders. The objective is to establish an unbiased and transparent calibration chain with minimal measurement uncertainties.

Regular round robin tests, a cornerstone of quality assurance, have been conducted by PTB and Fraunhofer ISE for years. These tests involve independent measurements of the same PV modules and solar cells under standard conditions, ensuring the calibration standard’s integrity. The institutions are planning to broaden their collaboration, incorporating additional methods such as measuring the solar module’s spectral response and expanding the range of measurements to encompass various module technologies.

This ongoing partnership reinforces the commitment of Fraunhofer ISE and PTB to uphold the highest standards in PV module measurements, contributing to the reliability and accuracy of the solar energy industry.