Short-term net load forecast in distribution networks with PV penetration behind the meter

In recent years there has been a strong expansion of photovoltaic (PV) distributed generation systems. A high PV penetration level can cause uncertainty in the operation and management processes carried out by electric utilities, since most meters register the net load, i.e., the actual load minus the power generated by the PV systems behind the meter. The goal of this paper was to analyze the difference in the net load forecasting error achieved by models using or not using behind-the-meter PV generation data. The PV plant is connected to the lower voltage side of the power substation, representing a penetration level of more than 35% of the total load. The study shows that the best forecasting results are obtained with an indirect approach using two forecasting models, one for the total load and the other for the PV generation. However, the difference with respect to the results obtained with a unique net load forecasting model is almost negligible, which may be of special interest for power system distributors or other agents who do not have access to behind-the-meter generation data.