Conceptual review and optimization of liquid air energy storage system configurations for large scale energy storage

Among energy storage systems, Liquid Air Energy Storage (LAES) is attractive because of high energy density, ease of being scaled up, absence of geographical constraints, mature technology and use of safe materials/working fluids. This work presents a critical review of LAES system configurations in the literature to identify the criteria behind their conceptual development. The goal is achieved following the HEATSEP methodology, which allowed identifying a common thread in the evolution of all LAES configurations in the literature based on very few layouts, named “basic configurations”. The optimization of these few layouts, taking into account all possible internal heat transfers, provides a unique and comprehensive overview of existing configurations in spite of their seemingly great complexity. This picture clearly indicates the link between topology and performance improvement and provides insight into the limits of the maximum possible performance gain over the existing literature. The optimal results show that the margin for improvement is quite narrow. In the case of a complete thermal integration between charge and discharge phases with the addition of Organic Rankine Cycle system a gain from 61.9 % to 64.3 % is obtained over the best performing configuration in the literature.