Comprehensive method for modeling uncertainties of solar irradiance for PV power generation in smart grids

Due to their intrinsic intermittent and random nature, renewable energy sources can dramatically influence the short-term scheduling of distributed energy resources (DER) and if their uncertainties are not properly handled, the operation strategies of DER may deviate from the optimal ones. In order to overcome this issue, this paper presents a comprehensive method for modeling uncertainties of solar power generation through a scenario-generation approach and historical data for a specific area of interest. The proposed approach is particularly suitable to be used in smart grid environment for stochastic operation optimization of DER. The Roulette Wheel mechanism has been used for generating an initial set of scenarios, and a reduction process based on Fast Forward method has been then applied in order to preserve the most representative ones, while reducing the computational efforts of next potential stochastic optimization phase. A sensitivity analysis has been carried out to evaluate the effects of key parameters on the solar irradiance generated scenarios. The results could be useful as a guide to tune scenarios' generation process aimed at obtaining scenarios with specific characteristics. Moreover, case study results show that the proposed method allows generating plausible scenarios for solar power generation to be used as input for DER stochastic optimization purposes. Moreover, its high flexibility allows to estimate the behavior of stochastic operation optimization of DER in the presence of more fluctuating, but ever plausible, solar irradiance patterns.