NOVELTY - The method involves transferring heat from a loading medium to a reversible heat transfer medium e.g. calcium chloride, in an indirect transfer region (110) without direct contact between the loading and heat transfer mediums, where the transfer medium changes into a loaded state by an endothermic reaction. The heat is transferred from the transfer medium to a discharge medium in a direct transfer region (114) by direct contact between the transfer and discharge mediums, where the transfer medium changes into an unloaded state by an exothermic reaction.    USE - Method for transferring heat from a loading medium e.g. liquid and/or gaseous water (all claimed), to a discharge medium, in an industrial plant. Can also be used for starting a fuel cell device.    ADVANTAGE - The combination of the indirect transfer region for transferring the heat from the loading medium to the heat transfer medium and the direct transfer region for transferring the heat from the heat transfer medium to the discharge medium enables heating the discharge medium in an energy-efficient manner. The heat is transferred from the loading medium to the heat transfer medium in the indirect transfer region without direct contact between the loading medium and the heat transfer medium, so that a chemical reaction of the loading medium with the heat transfer medium is prevented. The heat is transferred from the heat transfer medium to the discharge medium in the direct transfer region by direct contact between the heat transfer medium and the discharge medium, so that the discharge medium is chemically reacted with the heat transfer medium and heated by the heat released during the chemical reaction. The heat transfer medium changes into the loaded state by the endothermic reaction, so that energy is supplied to the heat transfer medium without heating the heat transfer medium. The method allows performing heat transformation without a need for supplying large energy, so that the heat transfer device is operated in a cost-effective manner.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a heat transfer device for transferring heat from a loading medium to a discharge medium.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a heat transfer device in which a loading medium supplying device and a discharge medium supplying device are not connected with each other.    Heat transfer device (100)    Container (102)    Loading medium supplying device (104)    Indirect transfer region (110)    Direct transfer region (114)