Enabling Renewable Energy—and the Future Grid—with Advanced Electricity Storage

Environmental concerns about using fossil fuels, and their resource constraints along with energy security concerns, have spurred great interest in generating electrical energy from renewable sources. The variable and stochastic nature of renewable sources, however, makes solar and wind power diffi cult to manage, especially at high levels of penetration. Electrical energy storage (EES) is necessary to effectively use intermittent renewable energy, enable its delivery, and improve the reliability, stability, and effi ciency of the electrical grid. While EES has gained wide attention for hybrid and electrical vehicle needs, public awareness and understanding of the critical challenges in energy storage for renewable integration and the future grid is relatively lacking. This paper examines the benefi ts and challenges of EES, in particular electrochemical storage or battery technologies, and discusses the fundamental principles, economics, and feasibility of the storage technologies.