Development of Heat Storage System Using Metal Hydride : 2nd Report, The Study of the Operation for Reducing Ineffective Hydrogen Quantity

Abstract

An innovated heat storage system with metal hydride (MH) applies for air conditioning of buildings is applied. In case of the heat storage systems using water and ice, the temperature of making cold water is almost is almost same as that of heat storage process. However, the temperature of heat storage process is about 35°C and that of making cold water is about 5°C, in case of the heat storage system using MH. The part of the absorbed hydrogen is used for cooling the heat storage vessel, MH and absorbed hydrogen, i.e., the absorbed hydrogen is not used for making cold water, through this process. The new concept, which is called the ineffective hydrogen quantity, is proposed for the purpose of estimating this hydrogen loss, i.e., the energy loss. Under this concept, the operation for reducing the energy loss and increasing the absorbed hydrogen per unit mass of MH is studied in this paper. As the main result, the ineffective hydrogen quantity is improved to 10% in our operation, while it remains to 29% in basic operation.