An apparatus for applying electromagnetic energy to an object in an energy application zone via at least one radiating element is disclosed. The apparatus may include at least one processor. The at least one processor may be configured to determine a value indicative of energy absorbable by the object at each of a plurality of frequencies and to cause the at least one radiating element to apply energy to the zone in at least a subset of the plurality of frequencies. Energy applied to the zone at each of the subset of frequencies may be a function of the absorbable energy value at each frequency.