An Overview of Hydrogen Storage Methods

Hydrogen is an attractive, pollution-free energy carrier, which is characterised in addition by a flexible and efficient energy conversion. Technology of hydrogen production is well developed and has advantage of practically unlimited basis of the raw materials. However, low density of hydrogen gas, low temperature of its liquefaction, as well as high explosive risk in combination with its negative influence on the properties of design materials bring to the forefront the problems of the development of effective and safe hydrogen storage systems. Namely these problems suppress at present the development of hydrogen power engineering and technology.This paper reviews the existent and prospective hydrogen storage methods, observes the dynamics of their development in the last three decades. The special attention is paid to metal hydrides, both as to their direct usage in the hydrogen storage systems and concerning the maintenance of the alternative methods, to improve their efficiency.On the basis of the analysis of available data, it is concluded that the best competitive position in the future will have combined systems realising several methods of hydrogen storage and processing. The methods could include small- and medium-scale metal hydride hydrogen storage units, as well as thermal sorption compressors providing gas-cylinder and cryogenic hydrogen storage systems. Buffer units for hydrogen storage, purification and controlled supply to a consumer could be in demand as well.