Photovoltaic power prediction and its application to smart grid

Photovoltaic (PV) output power prediction methods for various time horizon are investigated and their applications to smart grid are discussed. Moving average method including theoretical calculation of solar irradiance is applied to short term (10-30 minutes) prediction. Middle term (1 to several hours) prediction is used to compensate power fluctuation by battery storage system and/or balancing operation of demand and supply. Application to scheduling for charging of electric vehicle (EV) is also effective in this time horizon. Monte-Carlo simulation technique is applied to the middle term and long term (several hours to next day) prediction. A simulation model to predict the smoothing effect by multiple PV systems is also proposed. It is found that the proposed method can predict PV output power in 30 minutes with the average error of less than 5%, estimate the smoothing effects by assuming the correlation coefficients between multiple PV systems, and evaluate the PV power utilization rate for the EV charging system.