Carnot battery energy storage system integrated with liquid hydrogen cold energy: Thermodynamics, economic analysis and optimization

Carnot battery systems provide a high-energy-density storage solution that is not geographically constrained, converting and storing electricity in thermal form. However, the integration of Carnot batteries with cryogenic energy storage, specifically the utilization of liquid hydrogen cold energy, is an underexplored area. A pioneering design is presented in this study where a Carnot battery system is integrated with a liquid hydrogen cold energy utilization system. Additionally, it captures the waste heat from fuel cells to achieve combined generation of cold, heat, and power. The study includes steady-state modeling, sensitivity analysis of key components, and optimization using a particle swarm optimization algorithm aimed at maximizing power-to-power efficiency. The optimized system achieves a power-to-power conversion efficiency of 1.59, an energy efficiency of 1.02, an exergy efficiency of 0.18, and an Levelized Cost of Storage of 0.1516 USD/kWh. These findings represent a significant advance in energy storage technology, offering a new direction for integrating liquid hydrogen cold energy in energy storage systems and peak power applications.