Abstract
The article deals with the problem of electric power production in terms of environmental impact, in particular the energy efficiency of its production to utilize primary sources. The efficiency of its production directly depends on the composition of primary sources and technologies used. Difference in efficiency by converting various forms of energy into electrical power and their ratio in the use directly affect the resulting efficiency, production of emissions and thus the environmental impact. Electric traction, its production, is burdened less efficient than other types of tractions used in transport, but at the final reconciliation of their consumption in vehicles, this difference decreases or delays because the vehicles themselves work with different conversion efficiency of its traction on mechanical work, vehicle driving.