水素エネルギー社会とエンジンの役割

抄録

Demands for environmental protection and energy security stimulate the innovation toward the hydrogen society, in which various forms of the primary energy with a large variety of density are effectively used to produce hydrogen and electricity. Technological subjects in the hydrogen energy system relating to production, storage, transportation, and utilization are demonstrated. Hydrogen can easily produce electricity using engine and fuel cell, inversely electricity produces hydrogen using water electrolysis. The capability of hydrogen to be made from water is also one of the great advantages. That provides the ideal recycle use of water, in which hydrogen returns to water again after supplying heat and power. On the portability for vehicles, liquid fuel such as GTL and DME may also be easily synthesized by hydrogen. In particular, hydrogen fuel exhibits desirable characteristics for the combustion in spark-ignition engines. Wide range of flammability limits enables a smooth operation at a very lean mixture with low NOx level, thus the throttle control is unnecessary even at the idling condition in hydrogen engines. Experimental results of engine performance and NOx emissions are also shown using a single-cylinder test engine for a set of parameters.