Inter laboratory comparison of indoor performance tests on crystalline silicon solar PV modules

Abstract

The paper presents results from an inter laboratory comparison (ILC) of crystalline silicon PV module performance measurements from three different institutions within South Africa. The analysis quantifies the differences in power, current, and voltage measurements and compares power to the stated uncertainties for the measurements. The paper also explains the basics of PV module performance measurements, the link to PV module nameplate ratings, and describes the sources of uncertainty in the measurements. The results of the 2019 ILC I-V measurements among three South African institutions show differences of +/- 2.0% or less for maximum power measurements of crystalline PV modules, relative to the CSIR results. These differences are within the stated uncertainty for the measurements but greater than the +/-0.5% differences among international reference labs reported in a 2017.