Comparison of Indoor and Outdoor Performance Measurements on Cis Thin Film Solar Modules

In the present work we compare the indoor and outdoor performance of a set of CIS medium/large-area modules coming from different industrial/pilot productions. By comparing indoor to outdoor data we observe that the maximum power Pmax (Voc, and FF) measured indoors by our flashed solar simulator is systematically lower than the power measured outdoors. In the best cases the indoor measurement underestimates the Pmax by only 2.5%, in the worst case by more than 11%. Furthermore, for some devices we separately investigate the effects which lead to a discrepancy of outdoor to indoor data: (a) material¿s related quasi-stable effects, usually related to light soaking; (b) measurement related sweep-time effects: the influence of the duration of the IV scan when using a pulsed solar simulator; and by (c) what we define the pre-measurement state: the state in which the device is kept, sometimes for a very short interval (some ms), before the measurement. Moreover, we demonstrate that our pre-conditioning procedure (20 minutes of LS at 800 W/m2, T¿40°C and with a subsequent period of 15-30 minutes for adaptation to ambient conditions) significantly reduces the discrepancies between indoor and outdoor measurements for all the devices under test giving a more precise estimation of the outdoor performance of the module.

VIRTUANI Alessandro;  PAVANELLO Diego;  KENNY Robert;  NIKOLAEVA-DIMITROVA Miglena;  DUNLOP Ewan; 

2009-02-05

WIP - Renewable Energies

JRC40299

https://publications.jrc.ec.europa.eu/repository/handle/JRC40299,