A wireless energy transmission apparatus wirelessly transmits energy through resonance between a source resonator and a target resonator. The apparatus scans an amount of energy stored in the source resonator for a scanning period, calculates a total amount of energy stored in the source resonator and the target resonator during an off-resonant interval between the source resonator and the target resonator based on the amount of energy scanned, and estimates an amount of energy induced in the target resonator based on the amount of energy stored in the source resonator and the total amount of energy calculated.