High-Penetration PV Impact Analysis on Distribution Systems

Solar photovoltaic (PV) systems are expected to proliferate over the coming decade with most of these systems interconnected into the electric distribution system.  This new deployment is expected to challenge the utility industry in several ways. The first will be to understand what impact high-penetration PV output will have on utility distribution operation and practices. The second will be in finding ways to enable the existing electric grid to reliably integrate and distribute the PV energy to electricity users.

EPRI is currently leading a collaborative effort to assess how future high penetration of PV integrates into distribution feeders of various types and load mixes, and with different regional solar resources.  The effort includes developing and validating distribution feeder models, collecting and analyzing PV output characteristics as well as defining future PV scenarios and associated variability.   Using the model and available data it is possible to assess the effects of high penetration PV for a variety of actual distribution systems. Issues being addressed in this project include voltage regulation, equipment loading, reliability, power quality, safety, as well as newer communications and control that implement system-wide control such as conservation voltage reduction (CVR).  While this project is ongoing, this presentation will summarize some of the results thus far obtained via example case studies.