Benchmarking ERCOT Performance of Stem's Athena Optimization Platform

This technical report presents a detailed analysis of the performance of Stem's Athena® Optimization Platform within the Electric Reliability Council of Texas (ERCOT) market, focusing on energy storage systems in 2022. The report outlines the complexities involved in optimizing battery energy storage systems (BESS) for merchant markets, emphasizing the importance of advanced optimization capabilities for maximizing revenue. It includes a methodological overview of the benchmarking exercise, which analyzed six operational BESS assets across various ERCOT zones. The analysis compares actual revenue earned by these assets with potential revenue under different operational strategies, including a naïve forecasting approach and the fully automated Athena optimization. Key findings indicate that Athena's automated bidding outperformed most assets, achieving significant revenue gains through accurate price forecasting and optimization strategies. The report concludes with insights on the critical factors affecting BESS performance and the value of human expertise in conjunction with automated systems.