Design and global sensitivity analysis of a flexible hydrogen regasification process integrated with liquid air energy storage system

Abstract

This study presents an innovative power management system design that integrates a series of Brayton cycles and two regenerative Rankine cycles with a liquid air energy storage (LH-SBR-LAES) system, incorporating a liquefied hydrogen regasification process. This configuration offers enhanced flexibility in response to power demands, along with high energy efficiency and capacity. LAES is utilised as a storage medium because of its high flexibility, free availability, and potentially high cost-efficiency. Comprehensive thermodynamic and economic analyses were conducted to evaluate the feasibility of the proposed process. The results indicated a round-trip efficiency of 403.5 % and a net present value of $842.4 million, confirming the thermodynamic and economic viability of the process. The design configuration is complex and highly sensitive to each parameter in the system, posing challenges for process optimisation due to the variability of the operational input variables and the inherent uncertainties in their impacts. A global sensitivity analysis was conducted to identify the key variables affecting the specific energy output using Sobol' indices. This study underscores the importance of understanding the influence of these variables to optimize the design and operation of the LH-SBR-LAES process, thereby enhancing its overall efficiency and economic feasibility.