  By using the generalized version of the Shell Theorem analytical equations
are derived to calculate the electric energy of a charged sphere and the field
energy of the electrolyte inside and around the sphere. These electric energies
are calculated as a function of the ion concentration of the electrolyte. The
work needed to build up the charged sphere (i.e. the total charge-charge
interaction energy) decreases with increasing ion concentration of the
electrolyte because of the screening effect of the electrolyte on the
charge-charge interaction. The energy needed to build up the charged sphere
appears as sum of the field energy of the electrolyte and the polarization
energy of the electrolyte ions. At zero ion concentration the field energy of
the electrolyte is equal with the charge-charge interaction energy, while the
polarization energy is zero. At high ion concentrations 50% of the
charge-charge interaction energy appears as the polarization energy of ions,
25% as the field energy of the electrolyte inside the sphere and 25% as the
field energy of the electrolyte around the sphere.
