IEC TS 60904-1-2:2024 describes procedures for the measurement of the current-voltage (I-V) characteristics of single junction bifacial photovoltaic devices in natural or simulated sunlight. It is applicable to encapsulated solar cells, sub-assemblies of such cells or entire PV modules. For measurements of I-V characteristics of non-encapsulated solar cells, IEC TS 63202-3 applies.
The requirements for measurement of I-V characteristics of standard (monofacial) PV devices are covered by IEC 60904-1, whereas this document describes the additional requirements for the measurement of I-V characteristics of bifacial PV devices.
This second edition cancels and replaces the first edition published in 2019. This edition includes the following significant technical changes with respect to the previous edition:
a) The scope has been updated and refers to IEC TS 63202-3 for the measurement of non‑encapsulated solar cells.
b) The requirements for the non-uniformity of irradiance have been updated and now refer to classifications introduced in IEC 60904-9.
c) The requirement for non-irradiated background has been revised.
d) Spectral mismatch corrections are no longer mandatory, unless required by another standard. Spectral mismatch would have to be considered in the measurement uncertainty.
e) The requirement regarding the calculation of bifaciality has been modified: Equivalent irradiance shall not be calculated based on the minimum bifaciality value between ISC and Pmax, but on the bifaciality of ISC.