A technical specification for substation-size lithium-ion energy storage systems has been developed by a collaborative of approximately 17 utilities. The system is to be turnkey and transportable, with a nominal rating of 1 MW/2 MWh. The primary use of this system is anticipated to be utility peak management; however, other uses such as frequency regulation and intermittent resource integration are also desirable. The draft specification was first shared with utility sponsors to ensure that the broad outlines of their needs (use cases) were being met. The specification was then shared with lithium-ion manufacturers and system integrators who were judged by EPRI to have credible and serious market interest, as well as the capability to provide a demonstration system.
This specification can be used by utilities or other stakeholders in the procurement of grid-scale energy storage systems. It has been constructed in such a way to allow multiple uses for different projects, with no necessary alteration to the text in Sections 2 through 15. General requirements applying to all projects are provided in those sections, whereas project-specific requirements are relegated to Appendices A and B, in which representative data have been provided and must be replaced by the utility’s specific data. This specification is expected to evolve over time. This first release should help catalyze near-term deployment of more standardized energy storage products required by the electric power sector.