Renewable Systems Interconnection: Distributed PV Systems Design and Technology Requirements

ii Acknowledgments The authors wish to acknowledge the extensive contributions of the following people to this report. iii Preface Now is the time to begin planning for the integration of significant quantities of distributed renewable energy onto the electricity grid. Factors such as growing concern about climate change, adoption of state-level renewable portfolio standards and incentives, and accelerated cost reductions are driving steep growth in U.S. renewable energy technologies. In particular, distributed solar photovoltaic (PV) installations are showing very rapid growth. As distributed PV and other renewable energy technologies mature they can provide a significant share of our nation's electricity demand. However, as their market share grows, concern about potential impacts on the stability and operation of the electricity grid may create barriers to their future expansion. To facilitate more extensive adoption of renewable distributed electric generation, the U.S. DOE launched the Renewable Systems Interconnection (RSI) Study during the spring of 2007. This study addresses both the technical and analytical challenges that need to be tackled in order to enable high penetration levels of distributed renewable energy technologies. Given that integration-related issues at the distribution system are likely to emerge first for PV technology, the RSI study focuses on distributed PV technology. A key goal of the RSI Study is to identify R&D needed to build the foundation for realizing a high penetration renewable energy future while enhancing the operation of the electricity grid. The RSI study consists of 14 individual reports that address a broad set of issues related to distributed systems technology development, advanced distribution systems integration, system level tests and demonstrations, technical and market analysis, resource assessment, and codes, standards and regulatory implementation. This report is one of the 14 RSI reports. The full set of reports from the RSI Study is listed below: iv Addressing grid-integration issues is a necessary prerequisite for the long-term viability of the distributed renewable energy industry in general, and the distributed PV industry in particular. The RSI study is one step on this path. In addition, the DOE is working with a broad group of stakeholders to develop an R&D plan aimed at making this vision into a reality.