Zinc-air remains a promising fit for long-duration backup power applications despite technical immaturity

August 08, 2021 | Case Study

As California continues to experience an ongoing drought, wildfire season has become a yearly occurrence. Affected areas experience intermittent power outages, and in many cases, backup power is provided by fossil fuel energy sources for longer durations. Interday discharge remains a technical hurdle for energy storage technologies like Li-ion batteries, which can typically only discharge at their rated power for up to six hours. Using Li-ion batteries for baseload power would require substantial installed capacity and would make most projects too expensive to consider over incumbent solutions. Instead, energy storage systems (ESS) for backup power must be sufficiently low-cost to make up for low utilization rates and continuous power output. Our analysis of the levelized cost of storage (LCOS) across various technologies reveals that zinc-air batteries are the lowest-cost option for interday discharge. Zinc-air batteries have a low bill of materials, but their low cycle life and lower efficiency make them unattractive shorter-duration applications.