To obtain the useful data needed to optimize a future hydrogen combustion turbine system for electric power plants, this paper presents theoretical discussions on the steam-recirculating combined turbine system proposed by Graz University of Technology. This system consists of mainly a H2-02 stoichiometric combustion gas turbine cycle, a condensing turbine working in the bottoming cycle, and a high pressure turbine. All of these turbines work with the common steam. Authors investigate the performance and the exergy losses of this system by varying parameters such as turbine inlet temperature and bleeding ratio.
The Japan large space launch vehicle H-II is propelled by the high performance propulsion systems (LE-7 and LE-5B), they are using liquid hydrogen as the fuel. The combination of liquid hydrogen and liquid oxygen is known as the excellent performance propellant for the space launch vehicle. The particular physical properties of liquid hydrogen, such as a low boiling point, the space launch vehicles using hydrogen generally have skillful systems to certainly perform the ground and in flight operations.
The importance of hydrogen as a fuel will steadily increase in future, mainly due to environmental necessities. Currently, many major carmakers are developing electric vehicles with polymer electrolyte fuel cell(FCEV), expecting it to become one of the promising alternatives to replace gasoline-powered vehicles. This paper summarizes the latest progress of PEFC technologies and the FCEV’s, and the prospective contribution of them to introduction of wide use of hydrogen fuel in future is also discussed.
A feasibility study on lean-burn hydrogen fueled engines with high thermal efficiency and low emission has been carried out to demonstrate the application to hybrid electric vehicles by reviewing two papers [1,2]. The following conclusions have been obtained. (1) High thermal efficiency and emissions as low as EZEV (Equivalent Zero Emission Vehicle) level can be atained by lean-burn hydrogen fueled engines with reasonable acceleration and hill climbing performance. (2) A simulation study has shown that a range of 508 km as long as for a conventional gasoline car can be also obtained by series hybrid electric vehicle with the hydrogen fueled engine on board while using only 5kg liquid hydrogen equivalent to about 19 liters gasoline. The engine,at the same time,ca n overcome the emission level of EZEV. (3) Even if the engine system is a conventional reciprocating lean-bum hydrogen fueled engine,it gives NOx emission as low as 1/7.5 of EZEV level of NOx. The range is as short as 330 km but acceptable. (4) Lean-burn hydrogen fueled engines also give basically the same benefits as a fuel cell,with well-known technology that can be applied immediately.
Solar energy is the most abundant one among various renewable energy sources. However its defect is the low density, which prohibits commercial applications. Biological methods provide the way to accumulate the low density energy because the organisms grow by themselves to cover the area and to create automatically the devices of energy conversion as photosynthesis system. Ministry of International Trade and Industry Japan(MITI) has launched various projects for the development of new energy sources. This report summarizes a national R&D project of a biological hydrogen production. Scientific basis of the technology, the project organization and the research contents as approaches of genetic engineering and use of waste waters with a bench-scale reactors are described.