This substation energy storage specification is intended to facilitate utility procurement of large grid-connected electrical energy storage systems that would typically be connected at medium voltage at distribution substations. Few utilities have experience with devices of this type, and industry practices are not extensively developed. Therefore, this update report may be used as a guide to suppliers of these devices (who may be unfamiliar with utility practices) as well as distribution utilities (who may be unfamiliar with storage).
It is anticipated that each utility will follow its own procurement practices similar to those with other large equipment, such as transformers and switchgear. The details of bidding and commercial terms are therefore left to the utilities. However, this report is structured with the assumption that it will be an attachment or reference document in a commercial utility request for proposal (RFP). As such, it provides technical requirements related to design, manufacturing, shipping to the site, installation, testing, and operations and maintenance.