Carnegie Mellon Electricity Industry Center

2008-09 Seminars

The Role of Energy Storage in the Present and Future Electric Grid

Paul Denholm
Senior Analyst
National Renewable Energy Laboratory

Abstract
Energy storage is seen by many as a valuable source of energy and capacity services to existing utilities, and as an important component of a future grid, which may derive a large fraction of its energy from renewable energy sources such as solar and wind. Yet no large scale energy storage facilities have been built in the U.S. in over a decade, and wind energy advocates point to extensive studies that downplay the role of energy storage in the near future. This talk will attempt to cut through the hype surrounding energy storage and discuss the potential role of energy storage in the current and future grid, beginning with current utility perspectives on energy storage and the reasons for limited deployment of existing electricity storage technologies. The potentially increased role of energy storage due to large scale deployment of renewable energy will then be discussed and quantified, using the latest studies about the actual grid integration costs of RE, and the fundamental limits of RE to supply a very large fraction of the nation’s electricity supply. The presentation also will discuss current storage technologies, those under development, and competitors to energy storage such as demand response and plug-in hybrid electric vehicles.