Abstract
Hydrogen, which does not generate CO_2 by combustion, is considered to be an important (clean) energy source in near future. In the middle of 21st century, hydrogen energy society may be realized. In this study, several distributed hydrogen energy systems, which use hydrogen produced by water electrolysis, are dealt, and the energy costs for each system are evaluated. As a result, the energy cost using Brown's gas is greater than that of using the town gas in the case of present cost of equipment. However, in the case of 50% of the cost of equipment and cost of town gas of 100 yen/m^3, the case of Brown's gas is nearly equal to the case using town gas.
