This paper summarizes the impact of particulate material on solar-panel performance for systems located in the Colombian Caribbean Region. First, the dirt/particles are identified and classified; and then, their effect in the reduction of solar panel efficiency has been estimated at most of 6% during the times of the day with the maximum solar radiation. It has been found that the impact decreases exponentially for other hours during the day, which implies that dirt effect becomes negligible on the electric power available. The study reveals that the effect of dirt/particles is significant from a clean solar panel to one with light accumulation, but rapidly diminishes as accumulation changes from light to heavy. Thus, it is suggested that once some dirt accumulates on the panel, a cleaning procedure can wait until the particle accumulation is heavy without sacrificing efficiency excessively. The results of the study become a tool to estimate the trade-offs between power efficiency of photovoltaic systems and financial viability of those projects. Hence, inverters can be chosen such that they can limit the amount of electric power while minimizing the stochastic nature of solar radiation and the dirt/particle effect. The analysis presented starts through a complete Multivariate Analysis of Variance (ANOVA) considering three fundamental factors: dirt/particles, solar radiation and day.