Main text This report describes performing the international supplementary comparisons of the values ​​of colour coordinates and L *, a *, b * of reflecting surfaces transmitted by means of measurement standards - transfer standards from the participants of comparisons to the coordinating laboratory. These comparisons were carried out within the framework of the regional metrological organization (RMO) "Euro-Asian Cooperation of National Metrological Institutions" (COOMET) in accordance with the COOMET 743 / UA / 18 Project. The National Scientific Center "Institute of Metrology" (NSC "IM", Ukraine) acts as the coordinating laboratory for these comparisons. Supplementary comparisons are aimed at determining the degree of equivalence (DoE) for the National Photometric Laboratories participating in these comparisons. The DoE shows the deviation of the color coordinates and L *, a *, b * values ​​of the reflecting surfaces obtained by the Participant from the Reference Values (RV) ​​obtained between the National Photometric Laboratories participating in these comparisons. The comparisons will support the following CMCs from the classification of services in photometry and radiometry: color, reflection, Y, x, y,; color, reflection L *, a *, b *. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/. The final report has been peer-reviewed and approved for publication by the CCPR, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

One of the most important parameter used for the evaluation of the energy rating of PV modules is, their spectral responsivities which are the measure of electrical performance parameters per incident solar radiation. In this work, spectral responsivity measurements of a mono-crystalline, a poly-crystalline, a CIGS thin film and a bifacial module were measured using xenon-based flash type solar simulator system and a set of band pass filters. For the comprehensive characterization of parameters that may influence the spectral responsivity measurements, initially the simulator system was characterized both optically and thermally according to the IEC60904-9 and IEC60891 standard requirements. The optical characterizations in terms of spectral match, spatial non-uniformity and temporal instability indicate that the measured results (~3.0%, ~0.30% and ~0.20%) according to the IEC 60904-9 standard’s classification requirements correspond to A+A+A+ classes. Moreover, thermal characterizations in terms of the temperature uniformity show that over the 2 × 2 m area temperature uniformity of simulator system’s light distribution (1ºC) is almost two times better than the IEC 60891 standard requirements (±2ºC). Next, PV modules were electrically stabilized according to the IEC 61215-2 standard requirement’s (stability test) to reduce the fluctuations in their electrical performance parameters. Then, using the band pass filters, temperature controlled xenon-based solar simulator system and a reference PV module of the spectral responsivity of PV modules were measured from 400 nm to 1100 nm with 50 nm steps with relative uncertainty of 10-3 level.

Photovoltaic (PV) modules performance testing and energy rating as described in IEC 61853-1 standard depend on electrical performance parameters (short-circuit current, open-circuit voltage, maximum-power) of PV modules as a function of temperature and irradiance.In this work, in order to precisely determine the effects of temperature on the electrical parameters of a monocrystalline PV module, the temperature controlled, xenon light based solar simulator system with irradiance attenuating masks was used.This solar simulator, according to the IEC 60904-9 standard in terms of spectral match, spatial non-uniformity and temporal instability has A+A+A+ classes which are two times better than the standard requirements for a solar simulator to be used in PV module measurements.Moreover, the thermal chamber used in this work is a closed type chamber with fast opening door for not allowing the distortion of temperature uniformity over the surface of PV modules under test.Within about 2 m × 2 m area within 15˚C to 75˚C temperature interval, the temperature uniformity obtained for this system is less than 1.0˚C which is almost two times better than the IEC 60891 standard requirements (±2.0˚C).The temperature and irradiance dependent measurements of the electrical performance parameters of a mono-crystalline PV module at various irradiance levels and the evaluation of its temperature coefficients [α (% ˚C-1 ), β (% ˚C-1 ) and δ (% ˚C-1 )] were done by implementing the interpolation method described in IEC 60891 standard.

This work aims to determine the radiance responsivity to be used in the calibration of polychromatic radiation sources with low uncertainty using GUM and GUM Suplement-1. The spectral radiance values of the polychromatic lamps are obtained using the radiance responsivity of the system. The study aims to develop the derivation and better understand traceability of the other radiometric and photometric quantities with low uncertainty from the fundamental radiometric radiance unit. Measurement results obtained in the extended measurement uncertainty scale are determined using both classical and Monte Carlo methods.

The Euramet.PR-K2.a comparison on spectral responsivity for the wavelength range 900 nm to 1600 nm, as described in this report, was carried out to establish the degree of equivalence for the participating European laboratories with respect to the Key Comparison Reference Value (KCRV) of the CCPR-K2.a-2003 comparison. Seven laboratories, including pilot and link laboratory, participated. The comparison was piloted by VSL (Netherlands). Both VSL and NPL (UK) act as link laboratories to the CCPR-K2.a-2003 comparison. Most laboratories show a DoE within 1 % from the CCPR KCRV for almost the full wavelength range, with some slightly larger differences mostly above 1450 nm. One laboratory shows larger deviations, up to 3%. This report provides an overview of the comparison, a description of the characterization of the reference detectors, the data-analysis, participant results and their uncertainties and the degree of equivalence of participating laboratories with the CCPR KCRV. The full Technical Reports of the participants are included in the Appendix of the comparison report. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCPR, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).