Abstract: A heat storage device is disclosed in which grooves for supports supporting heat storage vessels, each vessel storing therein a heat storage material, are defined on the lower surface of each of the vessels so that the supports do not project from the bottom surface of each vessel.

Abstract: An absorption cold and warm water system utilizing solar heat in which heat source water obtained by heating water by the solar heat and a main heating source are used is selectively made to function as a warm water system, a first heat pump and a second heat pump in accordance with temperature conditions associated with the heat source water.

Abstract: An absorption cold and warm water system utilizing solar heat includes a low temperature heat generator using as a heating source low temperature warm water obtained by heating water by the solar heat, a high temperature generator using an ancillary heat source as a heating source when the system runs short of the solar heat, and a low temperature generator. The cold and warm water system is provided with an operation device operative, when the cold and warm water system is in condition in which refrigerating and heating outputs can be provided by using the low temperature warm water, to allow the low temperature warm water to be continuously fed to the cold and warm water system and to control the volume of a solution and a refrigerant in circulation in accordance with temperatures of the cold and warm water, to thereby store the solar heat in the cold and warm water system.

Abstract: In an absorption type cold and warm water system, a solution pump and a refrigerant pump are operated when a heat source serving as a drive source of the absorption type cold and warm water system is rendered inoperative as a result of the temperature of cold water and warm water produced by the system reaching an OFF value set beforehand for the heat source. This enables refrigerating and heating abilities stored in the cold and warm water system to be effectively utilized.