The article considers the issues of determining the main technical and economic indicators of the shunting locomotive during its modernization by a hybrid power plant. The analysis of scientific and practical works on the impact of railway transport on the environment and increase the efficiency of shunting locomotives due to design changes, which are aimed at reducing emissions. A model has been developed to determine the rational ecological and energy characteristics of a shunting locomotive, which has been modernized by technical means for energy saving taking into account the ecological component. A procedure, algorithm and program for calculating locomotive parameters have been developed. The main parameters of the shunting locomotive of the ChME3 type at modernization by its hybrid power plant taking into account an ecological component are defined and the estimation of expediency of such modernization is given.