Hydrogen can be stored in a variety of physical and chemical methods. Each storage technique has its own advantages and disadvantages. It is the subject of this study to review the hydrogen storage strategies and to survey the recent developments in the field. 1. Introduction
A volume of 11.2 Nm³ (the volume of the boot of a large utility or commercial vehicle) is needed to store just 1 kg of hydrogen, which is the amount required to travel approximately 100 km. Thus, for hydrogen storage to be economically viable, its storage density must be increased.
The hitch is that, while an excellent medium for renewable energy storage, hydrogen itself is hard to store. This is because it has a low volumetric energy density compared to other gases — such as natural gas — meaning it takes up significantly more space. Also, hydrogen has a boiling point close to absolute zero and requires cryogenic storage.
Another study referenced by a European staff working paper found that for large scale storage, the cheapest option is hydrogen at €140/MWh for 2,000 hours of storage using an electrolyser, salt cavern storage and combined-cycle power plant.
Du and Wu have measured hydrogen capacity of 2.55 wt% at 77 K and 40 bar over NaX (565 m 2 /g) and observed that at 20 °C and 40 MPa the value dropped to 0.4 wt% only. Chung studied various kinds of zeolites for hydrogen storage at 30 °C and found that USY has shown the maximum hydrogen capacity of 0.4 wt% at a pressure of 50 bar.
Except for CGH 2 and LOHC, one has to spend about one-third of the energy contained in hydrogen (LHV) or more to store it. LOHC is believed to be the most energy-saving hydrogen storage technology. However, this understanding is based on the full utilization of the heat released during the hydrogenation process.
OverviewPhysical storageEstablished technologiesChemical storageStationary hydrogen storageAutomotive onboard hydrogen storageResearchSee also
In this case hydrogen remains in physical forms, i.e., as gas, supercritical fluid, adsorbate, or molecular inclusions. Theoretical limitations and experimental results are considered concerning the volumetric and gravimetric capacity of glass microvessels, microporous, and nanoporous media, as well as safety and refilling-time demands. Because hydrogen is the smallest molecule, it easily escapes from containers and during transfer from container to container. While it does …