Techno-economic analysis of green hydrogen storage and transportation pathways

Abstract

To mitigate climate change and achieve global greenhouse gas emission targets, a great deal of effort is taking place in developing low-carbon solutions in the energy sector. Energy storage technologies are expected to play a crucial role in ensuring energy security by complementing intermittent renewable energy technologies. Green hydrogen is viewed as a promising energy storage solution considering its versatility. However, the lower volumetric energy density at ambient conditions is one of the drawbacks of hydrogen when its storage and transportation are considered. To tackle this problem, multiple promising options are reviewed in this study. This report examined the physical transportation of hydrogen in the form of compressed gas and liquified hydrogen, as well as the storage and transportation of it in chemical form. The latter category includes hydrogen carriers, such as green methanol, green ammonia, and LOHCs. Physical and chemical properties of the said hydrogen vectors, their dehydrogenation and the hydrogenation processes, as well as assumptions related to transportation are investigated in this report. Moreover, different international transportation routes for the import and export of the hydrogen are also considered. The UniSim Design R471 program is used to simulate the hydrogenation and dehydrogenation of the hydrogen vectors in order to determine the precise energy consumption, raw material needs, carrier production rate, etc. The total capital investment cost for each vector is calculated based on the simulations. A MATLAB model is built using the information from the literature research, the outcomes of the UniSim simulations, and the findings of the economic analysis. The MATLAB model's objective is to determine the LCOH for each hydrogen carrier supply chain. The model's finding show that supply networks using compressed hydrogen gas have the highest LCOH, whereas ammonia chains have the lowest LCOH, making them the most economical option. CO2 emission analysis showed that toluene - MCH chain has the highest CO2 emissions. However, both the LCOH and CO2 emissions can be significantly reduced by electrification of the dehydrogenation process.