There is a long history of using hydrogen flame. It is in 1837 when hydrogen-oxygen burner was invented in France. The researches of using hydrogen-oxygen flame for steel cutting were made actively in Japan before the Second World War. But at present, hydrogen is seldom used for the Steel cutting in the industrial field except for the steel cutting in the water. A lot of gas is used for the steel cutting in Japan. And it is equivalent to 400,000,000m³ of hydrogen per year on calorie bases. It is the purpose of this paper to make clear the pros and cons of using hydrogen for the steel cutting.

The stoichiometric H₂O₂ combustion in liquid water and that in steam are to be used for generation of superheated steam, in tum to drive an internal combustion steam turbine. The purpose of this work is to investigate the fundamental characteristics of the stoichiometric H₂O₂ combustion in liquid water for generating steam. Experiments both with a premixing and with a diffusion burner were carried out in a water tank under the atmospheric pressure. The temperature of the water was changed from room temperature to saturated temperature. In the water at the room temperature, the premixing burner obtained a high level(99.86%) of the combustion efficiency at stoichiometry of the supplied gas, but showed occasional flashbacks. In contrast the diffusion burner maintained stable combustion, but the combustion efficiency was lowed. By using partially premixing gases, the efficiency was improved to the level of the premixing burner, while the flames were kept stable. The influence of temperature of the water on the combustion characteristics is also presented.

Water molecule is decomposed easily to hydrogen and oxygen under the mild condition, i. e., under room temperature and 1 atm by electrolysis. Nevertheless thus obtained hydrogen and oxygen react vigorously and release much heat. Therefore we can get high temperature heat by combining electrolysis and combustion of hydrogen and oxygen. The idea has been proposed hitherto in Japan and also in the foreign counties, but only IS Plan got to produce the system, i. e., the aqua gas generator commercially in Japan. Here we shows the outline and the feature of the system. By the combustion of hydrogen and oxygen, the temperature of the flame gets to about 2000°C. Therefore, by means of the high temperature flame, it is easy to melt metals and also plastics to cut down or reform the surface of the materials. Such high temperature heat is also applied to decompose harmful organic chlorine compounds. Disposed waste materials are generally burned in the furnace but emission of hazard compounds are serious problems. The aqua gas generator solved the problems.

In order to detect hydrogen of gas concentration covering from 0.1 ppm to 100 vol%, the following three different types of hydrogen gas sensors are available: a hydrogen selective hot wire type semiconductor sensor (CH-H), a catalytic combustion type sensor (CS) and a gas thermal conduction type sensor (CT). CH-H can selectively detect hydrogen in the region from 0. 1 ppm to 1 vol%. CS is available for the detection of hydrogen from 0.1 to 4 vol% (the lower explosion limit of hydrogen) and has a rather poor selectivity to hydrogen. The above two sensors are applicable to hydrogen leak detection. CT is available for the detection of hydrogen from 1 to 100 vol% and is especially suitable for the control of hydrogen gas concentration in vol% order.

Fuel cells are a form of co-generation system that generate electricity directly through the electrochemical reaction of hydrogen and oxygen. High operating efficiency reduces the emission of CO₂ which causes the greenhouse effect. The Phosphoric acid fuel cell (PAFC) is the fuel cell technology that is closest to commercialization. This paper summarizes the latest progress of PAFC technologies at Mitsubishi Electric and introduce new system applications for 200kW PAFC power generation system. Systems include such as anaerobic digester gas fueled power generation system applied to sewage water sludge treatment center, bio-gas fueled power generation system applied to food industry (installed at the Tochigi Factory of Kirin Brewing Company) and a fuel cell power generation system combined with a gas turbine inlet air cooling system that utilizes steam which derived from PAFC (installed at the Yokohama Isogo Factory of Nisshin Oil Mills, Ltd.)

The application of carbon materials for the hydrogen storage system has attracted attention because of its distinctive future such as lightweight, abundant resources, non-toxicity and so on. In this report, the relation between the mechanism of hydrogen storage and the structure of various carbon materials are summarized.

Research and development activities of the WE-NET Phase I (FY1993-19D8) finished successfully at the end of March, 1999 and the Phase I program (FY199D-2003) started from April in succession.

In the Phase I we will give higher priority to the R&D on technologies that we expect to be commercialized in the near future (within 10 years) and in the mid-future (10-20 years from now). And we will continue the long-term R&D on which the research effort was focussed in the Phase I. The main results of the Phase I will be surveyed and the details of the Phase II plan will be introduced in this paper.