Techno-economic analysis of long-duration energy storage integrated with high-penetration renewable energy systems

Analyzing the economic and technical implications of integrating grid-level energy storage technologies into city-scale energy systems is critical due to the growing share of renewable resources in electric grids worldwide. This study evaluates the performance of six grid-level energy storage technologies: three electrochemical storage systems—lead-acid (LAB), lithium-ion (LIB), and flow batteries (FB)—along with three mechanical and chemical storage technologies—pumped hydro storage (PHS), compressed air energy storage (CAES), and hydrogen energy storage (HES). The energy system used in this study deploys solar PVs, wind turbines, and an auto-sized combined cycle power plant with an adaptable energy storage system capable of representing each of these storage technologies. Through Monte Carlo analysis, the study identifies the best, worst, and most probable economic outcomes for each storage technology within a high penetration renewable energy system. In a fully renewable scenario, the whole system’s most probable levelized cost of energy (LCOE) is estimated at $0.48/kWh for LAB, $0.38/kWh for LIB, $0.33/kWh for FB, $0.24/kWh for PHS, $0.15/kWh for CAES, and $0.27/kWh for HES. These findings offer valuable insights for energy analysts and decision-makers in selecting the most suitable energy storage solutions for grid-level applications.