Abstract: A heat transfer medium is used for a heat transfer system configured to transfer a cold of a refrigerant circulating through a refrigeration cycle device to an electric device. The heat transfer medium includes water and a lower alcohol that is at least one of methanol or ethanol.

Abstract: A heat transfer medium is used for a heat transfer system including a refrigerant cycle device through which a refrigerant circulates and a heat transfer medium circuit having a cooling target device. The heat transfer medium is cooled through heat exchange with the refrigerant and absorbs heat from the cooling target device while circulating through the heat transfer medium circuit. The heat transfer medium includes a carboxylate aqueous solution formed by dissolving carboxylate in water. Accordingly, by using the carboxylate aqueous solution as the heat transfer medium, a low viscosity at a low temperature can be secured. Further, since the carboxylate aqueous solution has a high heat exchange efficiency, the cooling capacity of the heat transfer medium can be improved.

Abstract: A heat transfer medium is used for a heat transfer system including a refrigerant cycle device through which a refrigerant circulates and a heat transfer medium circuit having an electric device. The medium includes an anhydrous liquid that does not contain water and is made of a substance having a polarity less than water. The anhydrous liquid is cooled by heat exchange with the refrigerant and absorbs heat from the electric device while circulating through the heat transfer medium circuit. Accordingly, the low viscosity of the heat transfer medium at a low temperature can be secured. Further, by using an anhydrous liquid without water as the heat transfer medium, it is possible to suppress an increase in an electrical conductivity of the heat transfer medium over time.