Trends and Opportunities in Electrochemical Storage

The rapid price declines and generation capacity expansion of solar photovoltaic power plants, along with the urgent need for elimination of CO
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in power generation motivates broad development of energy storage technologies to provide reliable power from intermittent solar power. Among the storage technologies available, this study focuses on electrochemical storage to explore trends and opportunities in current and future expansion. We provide a comparative analysis of the levelized cost of storage (LCOS) for various electrochemical storage options. We show that lithium (Li) ion batteries have overtaken previous battery technologies due to recent rapid price declines, and sodium (Na) chemistries hold promise for the future due to use of more Earth-abundant materials. Batteries dominate applications for short duration storage and compete with flow batteries for intermediate storage duration. For truly long duration storage, very low cost of energy capacity is required, and systems exploiting underground storage of hydrogen or low-cost storage tanks offer this possibility.