Evolution of cell cracks in PV-modules under field and laboratory conditions

Buerhop C, Wirsching S, Bemm A, Pickel T, Hohmann P, Nieß M, Vodermayer C, Huber A, Glück B, Mergheim J, Camus C, Hauch J, Brabec C (2017)

Publication Language: English

Publication Type: Journal article, Original article

Publication year: 2017

Journal

Progress in Photovoltaics Wiley-Blackwell

DOI: 10.1002/pip.2975

Abstract

Damaged modules, especially with cell cracks, can be observed quite often in photovoltaicinstallations.
Little knowledge exists about long‐term stability of precracked modules at real operating
conditions. Previous investigations and existing standards focus on the degradation of new,
defect‐free modules. This work highlights a twofold approach for life‐time study of precracked
modules: (1) outdoor exposure of 54 precracked modules for 1 year and (2) artificial stressing
of 20 representative precracked modules with a novel load test setup simulating snow and wind loads. The outdoor exposure reveals that at moderate weather conditions, no changes were detectable, neither in electric performance nor in EL‐images. However, the accelerated static load tests with stepwise increasing pressures point out that above a certain threshold, cracks grow.
Below this threshold, formerly unseen cracks become visible at the loaded stage. In addition,
modules with a smaller number of damaged cells have a stronger tendency to degrade further
than modules with an already large number of cracked cells. Remarkably, the power output measured with a solar simulator after a stress test up to 2500 Pa (describing conservative proof conditions for severe snow loads according IEC 61215) remains unchanged for almost all modules.

Authors with CRIS profile

Sven Wirsching Chair of Engineering Design Julia Mergheim Lehrstuhl für Technische Mechanik Christoph Brabec Institute Materials for Electronics and Energy Technology (i-MEET)

Involved external institutions

Bayerisches Zentrum für Angewandte Energieforschung e.V. (ZAE Bayern) DE Germany (DE) Allianz Risk Consulting GmbH, AZT DE Germany (DE) ADLER Solar Services GmbH DE Germany (DE) ECOlution Engineers UG DE Germany (DE)

How to cite

APA:

Buerhop, C., Wirsching, S., Bemm, A., Pickel, T., Hohmann, P., Nieß, M.,... Brabec, C. (2017). Evolution of cell cracks in PV-modules under field and laboratory conditions. Progress in Photovoltaics. https://dx.doi.org/10.1002/pip.2975

MLA:

Buerhop, Claudia, et al. "Evolution of cell cracks in PV-modules under field and laboratory conditions." Progress in Photovoltaics (2017).

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