Salt River Project says it and AES Corp. will build the utility's first standalone battery-based energy storage project.

The 10 megawatt, 40-megawatt-hour energy storage array, to be supplied by Fluence, will provide peaking capacity to the grid during high energy demand periods.

The project will be built in Chandler, Arizona, and was procured as part of an SRP effort to learn more about grid-scale battery storage. Mortenson will provide the engineering, procurement and construction for the balance of the plant portion of the project.

Under the 20-year agreement, AES will provide SRP with the battery-based energy storage system that will be charged by an SRP distribution substation. Fluence’s Advancion energy storage technology can deliver the energy equivalent to power about 2,400 homes in the greater Phoenix area for up to four hours.

Solar Powered Storage for APS

In February 2018, Arizona Public Service signed a 15-year power-purchase agreement with First Solar for peaking power from a 50 MW solar-powered battery.

First Solar will build and operate the facility that includes a 65-MW solar field to charge the battery. The field will store power when the sun is high in the sky and deliver it to customers between 3 and 8 p.m. when the sun is on its way down, but energy use is peaking.

The Energy Information Administration says that battery energy storage is used for a variety of ancillary services. Credit: EIAThe Energy Information Administration says that battery energy storage is used for a variety of ancillary services. Credit: EIAThe Arizona Public Service project adds to the three grid-scale batteries currently on APS’s system. Over the next 15 years, APS says it plans to adopt more than 500 MW of additional battery storage.

Regulatory Initiatives

In January 2018, Arizona utility regulator Andy Tobin proposed that utilities source 80 percent of their electricity from renewable and nuclear energy resources by 2050 and deploy 3,000 MW of energy storage by 2030.

A proposed "Clean Peak Standard" in Tobin's Energy Modernization Plan would require utilities to deliver an increasing portion of their renewable energy during peak demand hours. The state's consumer advocate offered a similar proposal in 2016.

On February 15, the Federal Energy Regulatory Commission voted 5-0 to remove what it said were nationwide barriers to the participation of electric storage resources in the capacity, energy and ancillary services markets operated by Regional Transmission Organizations and Independent System Operators.

In a November 2016 Notice of Proposed Rulemaking, the Obama-era FERC said that market rules designed for traditional generation resources can create barriers to entry for emerging technologies such as electric storage resources.