Comparing the Utility of Robust vs. Sparse Energy Storage Data Sets

Through a multi-year Energy Storage Performance analysis effort, EPRI collects and analyzes vast amounts of data from a variety of operational storage systems and public sources. This paper explores the different approaches, limitations, and benefits associated with sparse versus robust data availability by exploring examples from three recent data sets with differing levels of detail and resolution available for performance analysis. In order of robustness, these examples include 1) analysis of public CAISO curtailment reports and what they can and cannot tell us about energy storage system reliability, 2) analysis of relatively sparse timeseries data from an operational system that has shown operational limitations, and 3) analysis from an extremely robust data set and detailed investigations to identify troublesome low-level components (cells and modules).