An apparatus is disclosed for applying radio frequency (RF) energy to an object in an energy application zone via at least one radiating element. The apparatus is selected from a group consisting of sterilizers, pasteurizers, drying cabinets, sintering furnaces, curing furnaces, soil remediation apparatuses, smelting furnaces, melting furnaces and plasma generators. The apparatus comprises at least one processor configured to determine a value indicative of energy absorbable by the object at least one of or each of a plurality of MSEs; and cause RF energy to be supplied to the at least one radiating element in at least a subset of the plurality of MSEs, wherein energy supplied to the at least one radiating element at each of the subset of MSEs is a function of the value indicative of energy absorbable at each MSE.