Disaggregating solar generation behind individual meters in real time

Real-time photovoltaic (PV) generation information is crucial for distribution system operations such as switching, state-estimation, and voltage management. However, most behind-the-meter solar installations are not monitored. Typically, the only information available to the distribution system operator is the installed capacity of solar behind each meter; though in some cases even the presence of solar may be unknown. We present a method for disaggreagating behind-the-meter solar generation using only information that is already available in most distribution systems: advanced metering infrastructure, substation monitoring, and generation monitoring at a few PV systems nearby the circuit. The proposed method accurately predicts which homes have solar in over 90% of cases, and recovers the 15-min resolution PV generation signals with root mean square errors between 20% and 50% of average daily PV generation both historically and real-time. A sensitivity analysis shows the method to be robust to the number of buildings and time span of data used to fit. However including more than 3 solar proxies can cause false positive of PV systems behind meters. We find that the proposed method performs better at homes that export electricity to the grid more often.