Thermodynamics analysis of hydrogen storage based on compressed gaseous hydrogen, liquid hydrogen and cryo-compressed hydrogen

Abstract

Safe, reliable, and economic hydrogen storage is a bottleneck for large-scale hydrogen utilization. In this paper, hydrogen storage methods based on the ambient temperature compressed gaseous hydrogen (CGH2), liquid hydrogen (LH2) and cryo-compressed hydrogen (CcH2) are analyzed. There exists the optimal states, defined by temperature and pressure, for hydrogen storage in CcH2 method. The ratio of the hydrogen density obtained to the electrical energy consumed exhibits a maximum value at the pressures above 15 MPa. The electrical energy consumed consists of compression and cooling down processes from 0.1 MPa at 300 K to the optimal states. The recommended parameters for hydrogen storage are at 35–110 K and 5–70 MPa regardless of ortho-to parahydrogen conversion. The corresponding hydrogen density at the optimal states range from 60.0 to 71.5 kg m−3 and the ratio of the hydrogen density obtained to the electrical energy consumed ranges from 1.50 to 2.30 kg m−3 kW−1. While the ortho-to para-hydrogen conversion is considered, the optimal states move to a slightly higher temperatures comparing to calculations without ortho-to para-hydrogen conversion.