  We have investigated the effects of a non-thermal electron population on the
ionization and recombination rates. The considered electron distribution is
defined as a Maxwellian function below a break energy E_b and as a power-law
function of index alpha above this energy. We have calculated the collisional
(direct and excitation autoionization) ionization coefficient rates as well as
the (radiative and dielectronic) recombination rates. Practical methods are
given to calculate these rates in order to be easily included in a computer
code. The ionization rates are very sensitive to the non-thermal electron
population and can be increased by several orders of magnitude depending on the
temperature and parameters of the power-law function (E_b and alpha). The
non-thermal electrons have a much weaker effect on the (radiative and
dielectronic) recombination rates. We have determined the mean electric charge
of elements C, N, O, Ne, Mg, Si, S, Ar, Ca, Fe and Ni for different values of
the break energy and power-law index. The ionization balance is affected
significantly, whereas the effect is smaller in ionizing plasmas.
