California Energy Commission Grant Will Fund Long Duration Storage for Calif. Tribe

by Peter Maloney
APPA News
November 14, 2022

The California Energy Commission (CEC) earlier this month made a $31 million grant to fund a long duration energy storage system for the Viejas Tribe of Kumeyaay Indians in Southern California.

The grant is the first award under California’s $140 million Long-Duration Energy Storage Program, which is part of the state’s efforts to fight climate change and to achieve 100 percent clean electricity by 2045.

The CEC said the 60-megawatt-hour (MWh) project is one of the first of its kind in the country and will provide renewable backup power to the Viejas community in the event of local outages and provide the opportunity for the tribe to shift electricity use away from California’s electric grid during calls for conservation.

The CEC awarded the grant to Indian Energy LLC, a privately held Native American-owned developer that is building a microgrid project on the tribe’s behalf.

“This solar microgrid project will enable us to create a reliable and sustainable source of clean energy for our gaming, hospitality, and retail operations going forward,” John Christman, chairman of the Viejas Band of Kumeyaay Indians, said in a statement.

The Viejas Band is one of 12 bands of the Kumeyaay Indian Nation that lives on a 1,600-acre reservation in the Viejas Valley, near Alpine in San Diego County, where the tribe owns and operates the Viejas Casino and Resort.

The microgrid system is designed to deliver power to the casino and resort. The energy storage system will connect with an existing, onsite 15-MW solar power installation. Eos Energy Enterprises is supplying a 35-MWh, zinc-based flow battery to the project. Invinity Energy Systems is supplying a 10-MWh vanadium redox flow battery. The energy storage system will have the potential to discharge for up to 10 hours.

The remaining 15 MWh will also be non-lithium ion and will provided by the tribe at a later date, CEC spokeswoman Lindsay Buckley said via email.  The initial 45 MWh are scheduled to enter service by summer 2023, and we expect the full 60 MWh to be operational by the summer of 2024.”

Flow batteries use electrolytes moving through tanks to produce electricity. They are rechargeable and do not degrade. And, because they do not use lithium ion, they avoid the potential first hazards associated with those batteries.