UC San Diego

The ability to predict short-term fluctuations in irradiance is a necessary component of ensuring the reliability of a solar PV system at a given location. Local cloud phenomena that are responsible for these changes are dynamic and difficult to model; on-site measurements of irradiance provide an easy way to capture these effects. In this study, cloud movement is tracked in time through its effect on irradiance signals at different locations and compared with the estimates of the travel time from cloud speed data. The results showed a good correlation between the two different time lags for a short separation distance of 228m, but there was almost no relation for higher distances. Using different similarity measures like Correlation, Euclidean distance or the location of Local Minima for the signal analysis didn’t affect the results widely for a separation distance.