By Michael Gergen, David Pettit and Christopher Randall

The CPUC’s market-shaping decision provides guidance regarding the “stacking” of multiple electricity system services.

A new decision from the Public Utilities Commission of the State of California (CPUC) has set the stage for improved economic viability for California’s energy storage industry. The January 17 decision — Decision 18-01-003 in Rulemaking 15-03-011 (the Decision) — establishes a set of rules to guide utilities on how to “promote the ability of storage resources to realize their full economic value when they are capable of providing multiple [or ‘stacked’] benefits and services to the electricity system.”

To advance this objective, the CPUC has adopted 11 stacking rules to govern the evaluation of multiple-use energy storage applications, as well as associated definitions of services and service “domains.” The agency also established a working group to develop certain issues further and directed the CPUC’s Energy Division to prepare a report in 2018 on the state of the energy storage industry.