Spectral mismatch correction factor indicated by average photon energy for precise outdoor performance measurements of different-type photovoltaic modules

Outdoor performance of different-type photovoltaic (PV) modules ((1) heterostructure-with-intrinsic-thin-layer, (2) single-crystalline silicon back-contact, (3) multi-crystalline silicon, (4) CuInSe2, and (5) CdTe), which is short-circuit current (ISC), is measured using common single-crystalline silicon (sc-Si) PV module as PV module irradiance sensor (PVMS) with fast measurement time (below 200 ms). Errors between corrected ISC (outdoor measurement) and ISC (indoor measurement) under standard test condition (STC; AM 1.5G, 1 kW m−2 and 25 °C) of the PV modules are investigated. The corrected ISC of outdoor PV modules in the whole year is derived by correcting their measured ISC with a ratio of ISC of PVMS under STC to the measured ISC of PVMS for irradiance correction, thereby yielding the decrease in the error. Moreover, spectral mismatch correction factor (MMF) is also utilized for the correction of the measured ISC of different-type PV modules for the precisely corrected ISC. The average photon energy, indexing spectral irradiance, is proposed as an indicator of the MMF for the first time. Ultimately, median (−0.87%) and interquartile range (1.36%) of error for CdTe PV module are achieved by correcting the measured ISC using PVMS and MMF, although spectral response of CdTe PV module very different from that of PVMS.