Architects, engineers and urban planners have today at their disposal several tools for simulating the energy yield of photovoltaic systems. These tools are based on mathematical models that perform repetitive calculations to determine the annual irradiation received by solar panels; hence when photovoltaic systems are installed in complex urban environments, the simulations become highly computationally demanding. Here we present a simplified and yet accurate model for the direct calculation of the annual irradiation and energy yield of photovoltaic systems in urban environments. Our model is based on the correlation between the solar radiation components and the shape of the skyline profile. We show how calculations can be simplified by quantifying the skyline using two indicators: the sky view factor and the sun coverage factor. Model performance is evaluated in different climates using measured data from different photovoltaic systems. Results indicate that the proposed model significantly reduces the required computation time while preserving a high estimation accuracy.
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The data that support the plots within this paper and other findings of this study are available from the corresponding authors upon reasonable request.
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We thank the Dutch company Solar Monkey (www.solarmonkey.nl) for providing skyline profiles and annual AC yield measurements of PV systems monitored in the Netherlands for the validation of our model.
The authors declare no competing interests.
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Calcabrini, A., Ziar, H., Isabella, O. et al. A simplified skyline-based method for estimating the annual solar energy potential in urban environments. Nat Energy 4, 206–215 (2019). https://doi.org/10.1038/s41560-018-0318-6
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