This paper shows the current development status of hydrogen magnetic refrigeration, consisting of Carnot and AMR cycles. The world’s first Carnot hydrogen liquefier has been successfully constructed and tested. The magnetic material condenses gaseous hydrogen directly, enabling high thermal efficiency to be obtained. A Carnot efficiency of 54% and a condensation efficiency of 90% were attained. The simulation results for an entire hydrogen magnetic refrigeration system from 20 K to 300 K showed the high potential of magnetic refrigeration, which will allow the construction of hydrogen liquefaction plants with FOM＞0.5.

The organic chemical hydride (OCH) method for the hydrogen storage and transportation has both of the high gravimetric and volumetric hydrogen density. This method has low potential risk, because hydrogen is stored as the chemical liquid under the ambient pressure at the room temperature. However, this method has not been established technically, because dehydrogenation catalyst did not have been attained the enough stability and the sufficient performance. Chiyoda Corporation has developed the dehydrogenation catalyst for a fixed bed reactor with the high stability and the sufficient performance. This catalyst can generate hydrogen from methylcyclohexane (MCH :99.9%) with conversion: ＞95%, toluene selectivity: ＞99.9%, hydrogen generation rate: ＞1000 Nm3/h/ m3-cat under the reasonable condition of 593K (320℃), ambient pressure, LHSV:2.0h-1 and co-feed hydrogen:5～20mol% in feed. The hydrogen energy chain as a future global vision by OCH method is also proposed.

On board hydrogen storage is still under discussion because a suitable method has not been found. Major methods for on board application are introduced. Especially, hydrogen absorbing alloys attract attention because of large volume capacity. A technical development, a hybrid tank of compressed gas and hydrogen absorbing alloys, seems to be an ideal target in a short-medium term. Novel materials should be developed as a long term target.

The storage of hydrogen is a crucial issue for promoting various hydrogen energy applications, and one of the promising technologies is to store hydrogen in materials as hydrides. Some ternary hydrides exhibit the perovskite structure and the formation ability has been explained on the basis of the geometric factors. In NaMgH₃, the decomposition reaction proceeds in two steps, accompanying the desorption reaction with approximately 6.0 mass% of hydrogen. Moreover, the reversible hydrogen desorption and absorption reactions of NaMgH₃ were confirmed experimentally. Two occupation sites of hydrogen anion were indicated to be related to the two-step hydrogen desorption reaction. In CaNiH₃, the starting temperature of the hydrogen desorption is lower than 400 K. CaNiH₃ as a perovskite-type hydride is continuously transformed into Ca₂NiH₄ as a complex hydride, accompanied by partial hydrogen desorption and Ni precipitation during the thermal desorption process. Intermediate state between ionic and covalent bonding among Ni and hydrogen was suggested one of the origins of continuous transformation during the thermal desorption reaction.

Transport and storage technologies of hydrogen are essential for realizing the hydrogen energy society. Currently, various hydrogen storage mediums such as metal hydrides, chemical hydrides, compressed gas, and LH₂(liquid hydrogen) have been studying. However any mediums can not still meet the DOE targets of USA. LH₂ will be the most promising medium for transporting hydrogen as infrastructure. We have been developing transport and storage technologies of LH₂ under NEDO projects ;"WE-NET"(’93-’07) and "Development for Safe utilization and Infrastructures of Hydrogen (’03-’07)". This paper describes the LH₂ systems, their features, Kawasaki’s related business experiences, and current studies.

Sulfur-based hybrid cycle (SHC) process has been attracted much attention as a mass production process of hydrogen, which consists of an electrolysis step, 2H₂O + SO₂  H₂ + H₂SO₄ (353 K), and a thermal decomposition step, H₂SO₄  H₂O + SO₂ + 1/2O₂ (1123 K). To achieve high efficiency for hydrogen evolution, a development of the electrode materials with high corrosion resistance, high electrical conductivity and low anodic over-potential is a key technology for the electrolysis in H₂SO₄ solutions.

We found that some kinds of A-site deficient Ti-based pyrochlores (A³+₂Ti₄+₂O₇) showed high corrosion resistance in a 50 wt% H₂SO₄ solution at the oper ating temperature. Also, it was revealed that the electronic conductive ceramics had good electrical conductivity of 1 S/cm.

In this paper, we measured the electrical conductivity and corrosion resistance of perovskites (A²+Ti⁴+O₃), such as Gd_2-xTi₂O_7-δ and Sr_1-xTi_1-yNbyO_3+δ, in a 50 wt% H₂SO₄ solution at the operating temperature, and tried to coat Pd particles on the electronic conductive ceramics by electroless deposition technique in order to apply some catalytic property to the ceramics and measured the electrochemical properties of the Pd-coated electronic conductive ceramics.

A membrane reformer is based on the advanced concept of simultaneous generation and separation of hydrogen in a single reactor, which can make the reactions free from the limitation of chemical equilibrium. Because of these advantages, the membrane reformer can be made very compact and offers much higher efficiency than the conventional ones. We have manufactured and tested a membrane reformer with nominal hydrogen production capacity of 40 Nm³/h. The developed reformer was found to produce 40.1 Nm³/h of hydrogen with 99.999% purity at the energy efficiency of 76.2% (HHV). Additionally, under the partial-load operating condition, the reformer maintained the high energy efficiency of 69%. The system has thus been proved to give the highest efficiency in producing hydrogen from natural gas among various competing technologies.

Numerical simulation of hydrogen dispersion in a partially open space is performed in this paper. The transient behavior of hydrogen and the process of hydrogen accumulation in the space are discussed. Also, the effects of changing vent positions and conditions on the distribution of hydrogen concentration are shown. Based on the results, conditions for preventing dispersion and accumulation of hydrogen in the space are discussed.

The activity of research and development of hydrogen storage technologies in the hydrogen project proceeded by US DOE is reviewed according to reports at the 2006 Annual Merit Review Meeting held at Washington D.C on May 16-19, 2006.