Improvements perspectives of cryogenics-based energy storage

Abstract

Advanced exergy-based analyses provide the information for potential of improvement of energy- conversion systems from exergetic, economic and environmental point of view. These analyses are applied to Cryogenic-based Energy Storage (CES) also known as Liquid Air Energy Storage (LAES). Advantages such as (a) lack of geographical restrictions, (b) low environmental impact and the fact that it is (c) based on mature technology, drive further the research on this energy storage system. An adiabatic LAES system charged with Heylandt liquefaction of air process is analysed. Parameters such as exergy destruction, investment cost, cost associated with the exergy destruction, as well as the environmental impact associated with the thermodynamic irreversibilities are split into avoidable/unavoidable and endogenous/exogenous parts. Aspen Plus® software was used to simulate the LAES system and Engineering Equation Solver was used to conduct the conventional and advanced exergy-based analyses. The dependence of the improvement of each component with the rest of the system was found and all components present higher exogenous exergy destruction than endogenous. The component with the highest potential for improvement is the main heat exchanger in the discharge unit. Focusing on improvement of the components that were found to be the most inefficient ones with the highest exergy destruction, CES is expected to become thermodynamically and economically feasible.