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Energies 2018, 11(2), 294;

Organic Soiling: The Role of Pollen in PV Module Performance Degradation

Renewable Energies Chair, University of Evora, 7002-554 Evora, Portugal
Institute of Earth Sciences, University of Evora, 7000-671 Evora, Portugal
Hercules Laboratory, University of Evora, 7000-089 Evora, Portugal
Author to whom correspondence should be addressed.
Received: 14 December 2017 / Revised: 12 January 2018 / Accepted: 16 January 2018 / Published: 26 January 2018
(This article belongs to the Special Issue PV System Design and Performance)
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Soiling is a problem for solar energy harvesting technologies, such as in photovoltaic modules technologies. This paper describes not only one complete year of Soiling Ratioindex and rates measured in a rural environment of Southern Europe, but also focuses on the seasonal variation of the type of soiling, mainly spring and summer. The Soiling Ratio index is calculated based on the maximum power output and short circuit current of two photovoltaic (PV) panels, along with Scanning Electron Microscopy and Energy Dispersive X-Ray of glass samples to provide visual and chemical inspection of the type of soiling. Mass accumulation on glass samples mounted on a “glass tree” was weekly measured with a microbalance and related with the Soiling Ratio metrics. Soiling rates were calculated to infer the degree of soiling for each season and the respective comparison made. Results show a soiling rate of 4.1%/month in April (spring), 1.9%/month in July (summer) and 1.6%/month in September (fall). Rain (the main natural cleaning agent of the photovoltaic modules) as well as aerosol optical depth (proxy for atmospheric particle concentration) were correlated with the Soiling Ratio. In-depth analysis on the type of organic soiling was performed. View Full-Text
Keywords: solar energy; photovoltaic module performance; organic soiling; Scanning Electron Microscopy (SEM) solar energy; photovoltaic module performance; organic soiling; Scanning Electron Microscopy (SEM)

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Conceição, R.; Silva, H.G.; Mirão, J.; Collares-Pereira, M. Organic Soiling: The Role of Pollen in PV Module Performance Degradation. Energies 2018, 11, 294.

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