Open AccessStoring Renewable Energy in the Hydrogen Cycle
Author(s) -
Andreas Züttel,
Elsa Callini,
S. Kato,
Züleyha Özlem Kocabas Atakli
Publication year - 2015
Publication title -
chimia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.387
H-Index - 55
eISSN - 2673-2424
pISSN - 0009-4293
DOI - 10.2533/chimia.2015.741
Subject(s) - hydrogen storage , hydrogen , high pressure electrolysis , hydrogen production , hydrogen economy , cryo adsorption , hydrogen fuel , renewable energy , compressed hydrogen , liquid hydrogen , hydrogen technologies , energy storage , hydrogen fuel enhancement , energy carrier , hydride , electrolysis of water , chemistry , materials science , environmental science , electrolysis , thermodynamics , organic chemistry , physics , electrical engineering , power (physics) , engineering , electrode , electrolyte
An energy economy based on renewable energy requires massive energy storage, approx. half of the annual energy consumption. Therefore, the production of a synthetic energy carrier, e.g. hydrogen, is necessary. The hydrogen cycle, i.e. production of hydrogen from water by renewable energy, storage and use of hydrogen in fuel cells, combustion engines or turbines is a closed cycle. Electrolysis splits water into hydrogen and oxygen and represents a mature technology in the power range up to 100 kW. However, the major technological challenge is to build electrolyzers in the power range of several MW producing high purity hydrogen with a high efficiency. After the production of hydrogen, large scale and safe hydrogen storage is required. Hydrogen is stored either as a molecule or as an atom in the case of hydrides. The maximum volumetric hydrogen density of a molecular hydrogen storage is limited to the density of liquid hydrogen. In a complex hydride the hydrogen density is limited to 20 mass% and 150 kg/m(3) which corresponds to twice the density of liquid hydrogen. Current research focuses on the investigation of new storage materials based on combinations of complex hydrides with amides and the understanding of the hydrogen sorption mechanism in order to better control the reaction for the hydrogen storage applications.