This paper analyses the need of reintroduce electric transportation systems in countries that abandoned these modes and brings a methodology to assess the effectiveness of the electrification in terms of global warming mitigation. The potential interaction of grid connected vehicles and Smart Grids is presented among some ideas related to features that could be developed for massive transportation systems based on electric traction. As will be presented, Smart Grids could help to accelerate the electrification of transportation systems and the electrification could be used to accelerate the introduction of Smart grids. As reference cases in Colombia and Ecuador will be taken.