Dive Brief:

• A group of 11 community choice aggregators (CCA) in California last week issued a request for information (RFI) for storage technologies with a minimum duration of eight hours.
• The CCAs are looking at long-duration storage for long-term resource planning, according to the RFI. State regulators have found that meeting electric sector greenhouse gas reduction targets could require around 1 GW of long-duration storage in play by 2026.
• Depending on the responses to the RFI, some of the CCAs might launch a request for offers for long-duration storage, potentially as soon as this summer, CB Hall, senior power procurement manager at MCE, told Utility Dive. With the RFI, "we wanted to give the market a heads up that certain CCAs may be ready to move quicker than others," Hall said.

Dive Insight:

The California Public Utilities Commission (CPUC) approved a decision in April adopting a 46 million metric ton (MMT) greenhouse gas emission target for the electric sector by 2030 — while leaving the door open for a more rigorous 38 MMT goal — as well as the ideal resource mix to get to that point, including doubling current solar capacity, tripling battery storage, and adding in nearly 1 GW of either pumped hydro or some other kind of long-duration storage by 2026.

The RFI is a first step in identifying resources that could meet these needs. The 11 CCAs — which include MCE, the Clean Power Alliance of Southern California, CleanPowerSF and Silicon Valley Clean Energy — are open "to a wide variety of proposals," the request says.

But there are some requirements. Specifically, the CCAs are looking for technologies with a minimum eight-hour duration that can interconnect directly into either the transmission or distribution system and participate in the state’s electricity markets. In addition, they should qualify as "resource adequacy" resources with the CPUC and California Independent System Operator. 

Responses to the RFI are due July 1.

"With the long duration storage RFI, CCAs are starting early as these are long-lead-time resources. By collaborating in this way CCAs can optimize their resource planning and procurement efforts, achieve economies of scale, and save ratepayer costs," Girish Balachandran, CEO of Silicon Valley Clean Energy, said in an emailed statement. 

Long-duration storage can serve a variety of purposes as California zeroes in on its renewables targets, including providing flexible capacity, energy arbitrage in terms of soaking up excess solar in the middle of the day and shifting it to morning and evening ramps instead, and ancillary services, Hall said. While MCE is targeting resources with a minimum eight-hour duration, in keeping with the CPUC’s decision, looking ten years into the future, there could be a need for multi-day storage as well, he added.

California utilities, meanwhile, have mostly been considering long-duration storage at the pilot level, including as part of the California Energy Commission's Electric Program Investment Charge program, Jin Noh, policy manager with the California Energy Storage Alliance, told Utility Dive. And while the CPUC decision April decision looked at storage from a system perspective, "as we look at resiliency needs, contingency needs, local capacity constraints, what’s identified in the IRP [proceeding] could potentially be underestimating how much long-duration storage is actually needed," he added.

"This RFI is a real opportunity to demonstrate the capability and value that a diverse mix of long duration energy storage technologies can play in delivering clean, reliable power to Californians," Julia Prochnik, executive director of the Long Duration Energy Storage Association of California, said in an emailed statement. 

"We appreciate the CCAs initiating this inquiry as a necessary first step in developing a viable market in California for long duration energy storage, which will be critical to helping the state fight climate change and creating new jobs and economic opportunity for communities across the state," she added.