The invention relates, in general, to internal combustion engine cooling, in particular for a motor vehicle, more specifically to a cooling agent compensation tank of a cooling circuit, in particular a low-temperature circuit for indirectly cooling a super-charging air for an internal combusting engine and to a method for cooling a highly heated structure, in particular an internal combustion engine. The inventive compensation tank is integrated into a main cooling circuit, wherein a means for directly introducing the cooling fluid is arranged on the compensation tank between the input and output connections and the cooling fluid flow coming into the compensation tank runs directly from the input connection to the output connection by means of said directly introducing means.