California officials expect zinc energy-storage technologies to help the state attain 100-percent clean energy by 2045, proving cheaper and safer than lithium-ion while holding a charge longer.

“Some of them are looking for 25 to 50 hours of storage,” said Mike Gravely, research program manager at the California Energy Commission.

“Some of them are looking to provide residential homes the storage they need to ride through these PSPS (public-safety power shut-off) events that California has, or to provide the reliability and resiliency that a home should have, and they’re in the size that they would fit in your garage, or they would fit something about the size of your outside air conditioner.”

California recently invested $16.8 million in energy-storage technologies beyond lithium-ion, many of which employ zinc.

“If you look past lithium ion, probably zinc is the next metal that’s the most popular for energy storage, and it it does appear to be able to provide performance equal to or better than lithium if given a chance,” Gravely said in a webinar hosted by the Clean Energy States Alliance. “So we have projects where we’re doing zinc batteries at the residential level, the commercial level, and the industrial level.”

The state plans to install 2,400 megawatts of energy-storage through 2023, about 90 percent of which are based on lithium-ion technologies. But state officials estimate they will need another 20,000 to 30,000 MW of energy storage by 2045.

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Lithium-ion dominates the short-term outlook largely because investors will support it, Gravely said, and investors have been reluctant to venture beyond lithium-ion. The grants—going to companies including E-Zinc, Salient Energy and Anzode Energy—are