PV power output uncertainty in Australia

Uncertainty in power output of photovoltaic (PV) plants has raised concerns in regard to the interconnection of PV plants to the power systems. Climate conditions vastly affect the uncertainty of output power; however, aggregation of PV plants is potentially able to reduce the uncertainty; hence, the effectiveness of aggregation should be evaluated for climatically diverse locations. In this paper, an analysis has been performed to investigate the uncertainty in Australia by considering seven utility scale plants. A PV predictive model taking into account the PV module temperature is used to predict the output power for the modeled PV plants. Temporal and spatial ramp rate analysis is performed to characterize the level of uncertainty and evaluate the level of reduction in uncertainty through aggregation. Besides, it is validated that 1-min and 5-min ramp rates becomes uncorrelated on the order of 1 km and 20 km, respectively.