This work presents a synthesis of the technical, environmental and financial studies that contributed to the reintroduction of grid-connected alternatives into the planning of mass transportation systems in Colombia.With this effort, the Universidad Pontificia Bolivariana has played a decisive role in the reintroduction of trolleybus and tram systems in Colombia, which is fundamental to achieve the electrification of the transportation sector.The consequences of the electrification are a reduction in fossil fuel composition, air quality improvement, public health, and travel comfort upgrade.