From a fundamental and technological perspective energy transfer up-conversion in luminescent solids is a very important phenomenon that requires different viewpoints for understanding and modeling. The efficiency of this process increases in the presence of energy migration. In this work a model to study the energy migration effects on the up-conversion process for doped solid time-dependent luminescence is proposed. The model takes advantage of the Forster-like method to calculate the relevant quantity averages and a microscopic-macroscopic methodology to solve energy transfer mixed schemes. Along with adequately describing the experimental trends reported in the literature for the relevant involved states, the model separates the migration-excited transient population from the initially excited time-dependent population, which permits, separate analysis of the dynamics of the components. This last aspect is difficult to achieve experimentally and, to our knowledge, has not been reported previously in the theoretical literature.