  We discuss the concept of energy packets in respect to the energy transported
by electromagnetic waves and we demonstrate that this physical quantity can be
used in physical problems involving relativistic effects. This refined concept
provides results compatible to those obtained by simpler definition of energy
density when relativistic effects apply to the free electromagnetic waves. We
found this concept further compatible to quantum theory perceptions and we show
how it could be used to conciliate between different physical approaches
including the classical electromagnetic wave theory, the special relativity and
the quantum theories.
