This review highlights the latest advancements in thermal energy storage systems for renewable energy, examining key technological breakthroughs in phase change materials (PCMs), sensible thermal storage, and hybrid storage systems. Thermal storage technologies have the potential to provide large capacity, long-duration storage to enable high penetrations of intermittent renewable energy, flexible energy generation for conventional baseload sources, and seasonal energy needs. It allows surplus thermal energy—sourced from heat or cold environments— o be stored and retrieved when needed, enhancing energy management flexibility. Practical applications in managing solar and wind energy in. Utility-scale systems now cost $400-600/kWh, making them viable alternatives to traditional peaking power plants, while residential systems at $800-1,200/kWh enable homeowners to achieve meaningful electricity bill savings through demand charge reduction and time-of-use optimization. Technology. Battery Storage Dominance with Rapid Cost Decline: Lithium-ion batteries have become the dominant energy storage technology, with costs falling over 85% since 2010 to $115/kWh in 2024. This dramatic cost reduction, combined with 85-95% round-trip efficiency and millisecond response times, has made.
