The world is moving towards zero CO2 production and limiting the global temperature increase to 1.5°C by 2050 by reducing the use of fossil fuels as an unsustainable energy source. As a transition from this reduction, electric energy has become the primary energy source in the industrial, transportation, construction, and other sectors. In the transportation sector, urban electric trains have become a preferred mode of transportation by people worldwide due to their high safety and service levels compared to other land transportation. However, electric trains require a significant amount of energy to operate, so efforts are needed to optimize total electricity usage. This paper provides a literature study related to electric energy efficiency in the field of urban electric trains, using train control methods and the utilization of regenerative braking systems as the most efficient energy recovery strategy.
