Trends and status of battery energy storage for utility applications

Since the early 1970s, there has been a steady effort to introduce batteries to the electric utility industry for large scale energy storage in a load leveling mode. Utilities, on the other hand, have been relatively indifferent to this technology for a number of technical and institutional reasons that primarily involve the economic viability of this technology in the load leveling mode. However, from the late 1980s and early 1990, the concept of using batteries primarily for load leveling has undergone a radical change as a result of analytical studies as well as changes in hardware design practice. Now, batteries are being promoted for a wider range of high value applications that go beyond load leveling, and potentially affect the transmission and distribution as well as customer-side operations of the electric utility. As a result, utilities are showing a renewed interest in battery energy storage and several utilities are evaluating battery energy storage projects. This paper discusses the significant trends that are driving the renewed utility interest in this technology and reviews the status of ongoing utility projects