The Doctoral Thesis is devoted to the study of a solution for improving the energy efficiency of electric public transport by using mobile supercapacitor-based energy storage systems. The modelling variants of electric transport overhead DC lines for the simulation of total energy consumption are analysed. It was found that the additional mass of a mobile energy storage system does not increase the energy consumption of the electric transport by more than 5 %, while the possibility of storing the energy recovered during braking reduces the total energy consumption from the supply substation by up to 40 %. A method for the design of a mobile energy storage system is described, considering the amount of energy to be recovered and the progressive deterioration of the supercapacitor cell parameters. It is found that the cost of energy saved during the lifetime of the supercapacitors is significantly higher than their cost of purchasing and installing, especially at higher electricity prices.