An Overview of Invisible Solar Generation Estimating Approaches

In recent decades, residential and commercial solar photovoltaic (PV) systems have been increased. However, most of these PV systems are not monitored by power system operators. Thus, they are called invisible solar power or behind-the-meter (BTM) solar sites. The presence of these types of PV sites could pose many new challenges to the analysis of hosting capacity, net load forecasting for feeders, or volt-ampere-reactive (VAR) control. To handle these system operations, numerous approaches have been developed to estimate invisible or behind-the-meter solar generation. This paper presents a complete literature review about the estimation techniques for invisible solar generation, providing an important reference to power system operators. These up-to-date estimation techniques are classified into two categories, i.e., data-driven methods and model-based methods. This paper will summarize the required data for each method and study their strengths and drawbacks for PV estimation.