A heat converter according to one embodiment of the present invention comprises: a plurality of unit modules respectively arranged in a first direction and a second direction that intersects the first direction; and a frame, which supports the plurality of unit modules, allows cooling water to flow in through one surface arranged in the first direction, and allows the cooling water to be discharged through the other surface arranged in the first direction, wherein each unit module includes: a cooling water passage chamber having first and second surfaces arranged to be spaced in the first direction, third and fourth surfaces arranged to be spaced in a third direction that intersects the first direction and the second direction, a fifth surface arranged to be spaced in the second direction such that cooing water flows therein, and a sixth surface from which cooling water is discharged; a first thermoelectric module arranged on the first surface; and a second thermoelectric module arranged on the second surface, the first thermoelectric module includes a plurality of group thermoelectric elements, each group thermoelectric element includes a plurality of thermoelectric elements, which have the same minimum spacing distance from the fourth surface in the third direction, and the plurality of thermoelectric elements in at least one group thermoelectric element of the plurality of group thermoelectric elements are electrically connected to each other.