Comparison of hydrogen and methane storage by means of a thermodynamic analysis

Hydrogen from renewable resources is a potential substitute for common fossil energy carriers. Especially the use of hydrogen as a future carbon-free road transport fuel offers both ecological and economic benefits. Currently, high-pressure hydrogen storage is the technology most applied in vehicles and the majority of fueling stations are equipped exclusively for refueling with compressed hydrogen. For a nationwide application of compressed gaseous hydrogen as a road transport fuel the usage of a delivery infrastructure similar to the existing one for natural gas is conceivable. Consequently, a comparison of the behavior of hydrogen and methane with respect to typical thermodynamic storage processes is useful. In the beginning important properties of hydrogen and methane are compared. Based on this different thermodynamic processes for expansion and compression are investigated. In addition the refueling of a vehicle storage tank is examined, with particular emphasis on the influence of the Joule-Thomson effect. Finally, the pressure and temperature change within a salt cavern is analyzed. All computations were performed using the numerical software MATLAB®.