Reliability of liquid organic hydrogen carrier-based energy storage in a mobility application

Abstract

Liquid organic hydrogen carriers (LOHC) are a technology that allows storing hydrogen in a safe and dense manner by reversible chemical conversion. They constitute a very promising option for energy storage, transport, and release combined with electric power generation by fuel cells in large-scale applications like trains. In order to establish trains running on LOHC, it is mandatory to ensure the reliability of the system. This study evaluates various system configurations concerning reliability and resilience. The fault tree analysis method has been used to quantify the probability of failure. The S-P matrix was applied to assess the different failure modes in context of severity as well as their probability. The MTTF of the system can be more than doubled by introducing single redundancy for the fuel cell and the reactor, while more than two redundant components diminish the positive effect on reliability due to higher complexity. It is estimated that the systems full functionality is available for more than 97% of its operating time.