The power system is currently undergoing a major transition, with increasing levels of renewable resources being connected to the grid and displacing conventional generation. Many of these resources are connecting not to the transmission system, as had been the convention in the past, but directly to the distribution system in the form of distributed energy resources (DERs). With the introduction ...

Distribution planners are being faced with a new reality — the vast majority of change to the distribution system is occurring due to the addition of distributed energy resources (DER). The result is a new set of challenges when planning and integrating DER. Just as capacity planning studies are performed for accommodating new load, hosting capacity planning studies are needed for accommodating new DER. To meet this challenge, the industry needs a system-wide method to plan for and integrate DER into the distribution system. This paper will describe the Distribution Resource Integration and Value Estimation (DRIVE) module developed by EPRI, the implementation of that module in distribution planning software, and the data needed to successfully use this module to determine distribution-wide hosting capacity.

In 2011, EPRI began a four-year effort under the Department of Energy (DOE) SunShot Initiative Solar Energy Grid Integration Systems - Advanced Concepts (SEGIS-AC) to demonstrate smart grid ready inverters with utility communication. The objective of the project was to successfully implement and demonstrate effective utilization of inverters with grid support functionality to capture the full value of distributed photovoltaic (PV). The project leveraged ongoing investments and expanded PV inverter capabilities, to enable grid operators to better utilize these grid assets. Developing and implementing key elements of PV inverter grid support capabilities will increase the distribution system’s capacity for higher penetration levels of PV, while reducing the cost. The project team included EPRI, Yaskawa-Solectria Solar, Spirae, BPL Global, DTE Energy, National Grid, Pepco, EDD, NPPT and NREL. The project was divided into three phases: development, deployment, and demonstration. Within each phase, the key areas included: head-end communications for Distributed Energy Resources (DER) at the utility operations center; methods for coordinating DER with existing distribution equipment; back-end PV plant master controller; and inverters with smart-grid functionality. Four demonstration sites were chosen in three regions of the United States with different types of utility operating systems and implementations of utility-scale PV inverters. This report summarizes the project and findings from field demonstration at three utility sites.

Distribution planners are facing a new reality: the vast majority of new generation currently being connected to the grid is through the distribution system. This "edge" of the grid, where utilities have the least amount of visibility and controllability, is also where most of the change is occurring. The result is a new set of challenges associated with further integrating these ever increasing levels of distributed energy resources (DERs). To meet these challenges, an integrated approach for planning is needed.

The third solicitation of the California Solar Initiative (CSI) Research, Development, Demonstration and Deployment (RD&D) Program established by the California Public Utility Commission (CPUC) is supporting the Electric Power Research Institute (EPRI), National Renewable Energy Laboratory (NREL), and Sandia National Laboratories (SNL) with collaboration from Pacific Gas and Electric (PG&E), Southern California Edison (SCE), and San Diego Gas and Electric (SDG&E), in research to improve the Utility Application Review and Approval process for interconnecting distributed energy resources to the distribution system. Currently this process is the most time - consuming of any step on the path to generating power on the distribution system. This CSI RD&D solicitation three project has completed the tasks of collecting data from the three utilities, clustering feeder characteristic data to attain representative feeders, detailed modeling of 16 representative feeders, analysis of PV impacts to those feeders, refinement of current screening processes, and validation of those suggested refinements. In this report each task is summarized to produce a final summary of all components of the overall project.

This paper will describe work done at EPRI over the past several years in relation to energy storage and bulk power system integration of renewables. In particular, applications of energy storage and related functional requirements are described and technologies are summarized. Insights and lessons learned from various case studies are also examined, showing the impact of energy storage on bulk system integration of variable generation.