This paper focuses on the findings outputted by a comprehensive measurement campaign carried out for characterizing and modeling Brazilian outdoor and low-voltage electric power grids for data communication purposes. In this regard, the statistics of average channel attenuation, root-mean-square delay spread, coherence time, coherence bandwidth and achievable data-rate are analyzed by considering the frequency band from 1.7 MHz up to 100 MHz, and thereof statistical models for some channel features are recommended. The periodic variation of these outdoor and low-voltage electric power grids is quantified and presented as a temporal function of the average channel attenuation. Also, mathematical models based on only two parameters representing the power spectral density of both background and impulsive noises are proposed. The results obtained from numerical analyses offer important information about Brazilian outdoor and low-voltage electric power grids for data communication purposes. Also, they constitute an opportunity for increasing the knowledge about this kind of data communication media and for assisting the design of new generations of effective and reliable power line communication systems.