Cloud Advection and Spatial Variability of Solar Irradiance

A model for predicting smoothing of solar irradiance by spatially distributed collectors was analyzed. The model assumed cloud advection dominates the relationship between sites and represented the distributed plant with a transfer function. The transfer function representing the smoothing effect was shown to be the Fourier transform of the plant's spatial distribution, and as such, the plant represents a low-pass filter. Comparison with measured data from the HOPE-Melpitz campaign showed that the model is able to replicate dynamics present in the measured plant transfer function and showed good frequency domain agreement. Generalization of the approach is needed for broader applicability, as the current analysis only validated against one-dimensional, advection dominated conditions. However, the approach warrants further study as it has demonstrated an ability to reveal frequency domain characteristics not currently reflected by state-of-the-art models.