Electrical and Computer Engineering Publications

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Renewable Energy

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There has been a recent surge in interest in the more accurate snow loss estimates for solar photovoltaic (PV) systems as large-scale deployments move into northern latitudes. Preliminary results show bifacial modules may clear snow faster than monofacial PV. This study analyzes snow losses on these two types of systems using empirical hourly data including energy, solar irradiation and albedo, and open-source image processing methods from images of the arrays in a northern environment in the winter. Projection transformations based on reference anchor points and snowless ground truth images provide reliable masking and optical distortion correction with fixed surveillance cameras. This allows individual PV module-level snow shedding ratio determination as well as average cumulative snow load by employing grayscale segmentation. The data is used to determine the no-snow losses of two systems during summer and snow losses during winter. The results found monofacial snow losses are in average 33% for winter period, and 16% on an annual basis. Bifacial systems perform better than monofacial in severe winter conditions as average winter snow losses was 16% and the annual losses were 2% in the worst-case scenario. In addition, there was a bifacial gain of 19% compared to monofacial system during winter.

Creative Commons License

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.

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