By using the equation of motion for the dynamic response of the σ and π electrons in the carbon nanostructure, the classical Poynting theorem of conservation of electromagnetic energy is extended so as to be applicable to derive an exact expression for the time-averaged electromagnetic energy within an isolated C60 molecule, which is irradiated by a plane and time-harmonic electromagnetic wave. Numerical results show that the stored energy exhibits resonant enhancement near resonances of extinction cross section of the system.
