The Washington Utilities and Transportation Commission (the “WUTC”) is in the midst of an investigation into methods for modeling the costs and benefits of energy storage in utility integrated resource plans (“IRPs”). During its review of the 2013 IRPs of Washington’s regulated utilities (Puget Sound Energy (“PSE”), Avista, and PacifiCorp), the WUTC directed the utilities to start considering how energy storage could be incorporated into future IRPs. As part of this effort, WUTC staff issued a white paper in May 2015: Modeling Energy Storage, Challenges and Opportunities for Washington Utilities. On August 7, the WUTC noticed a comment period on the white paper; the comment period closes on September 25, 2015. The WUTC will use the comments received during this period to determine whether it is necessary to give utilities direction on how energy storage should be treated in their planning and procurement processes, and may issue a policy statement at the end of the investigation to provide that guidance.