The California Public Utilities Commission (CPUC) has officially set an energy storage target of 1.325 GW for Pacific Gas and Electric Co. (PG&E), Southern California Edison, and San Diego Gas and Electric. The decision, pursuant to A.B.2514, directs the utilities to file separate procurement applications containing a proposal for their first energy storage procurement period by March 1, 2014.
The decision further establishes a target for community choice aggregators and electric service providers to procure energy storage equal to 1% of their annual 2020 peak load by 2020 with installation no later than 2024, consistent with the requirements for the utilities.
The decision is the result of a two-year regulatory process that studied a variety of energy storage technologies and applications for meeting the state's growing grid needs. All five CPUC commissioners approved the final decision, which was issued in draft form in September.
‘This decision represents an important first step in encouraging the storage market and supporting grid reliability," says Carla J. Peterman, lead commissioner for the proceeding.
The California Energy Storage Alliance (CESA), an advocacy group, says some of the highlights of the decision include the following:
- Specific, biennial energy storage procurement targets for the three large investor-owned utilities beginning in 2014, with targets increasing over time. By 2020, the three together are expected to have contracted for 1.325 GW of energy storage for their operations with an installation requirement no later than 2024;
- Utilities will be allowed to employ energy storage for a variety of functions throughout the electric power system, such as capacity, ancillary services and peak shaving;
- Energy storage systems can be deployed in three ‘grid domains’: transmission-interconnected, distribution-interconnected and behind-the-meter-interconnected; and
- Utility ownership of storage projects should not exceed 50% of all storage across all three grid domains.
While large-scale pumped storage (>50 MW) projects are excluded from the target, the CESA says the CPUC will hold a workshop to further explore the operational characteristics and uses for pumped storage projects.
In May, PG&E and the California Energy Commission unveiled the Yerba Buena Battery Energy Storage System Pilot Project, which charges batteries when demand is low and then sends reserved power to the grid when demand grows. PG&E says the pilot includes utility-scale sodium-sulfur battery energy storage, has a 4 MW capacity and can store more than six hours of energy.