This article presents four case studies carried out in the city of Bogotá - Colombia, on the reduction of emissions in private transport vehicles using Hydrogen Generators (HGE) by water electrolysis (electrolytic cells). The article proposes a possible scenario for the reduction of greenhouse gas emissions (GHG), as a result of the decrease in regular gasoline consumption due to the use of HGE in the case studies. The analysis focuses on the direct GHG (carbon dioxide - CO2, methane - CH4 and nitrous oxide - N2O) emitted in the combustion of gasoline engines, because they are gases of slow removal through physical, chemical and biological processes of the earth. The analyzes carried out show that the use of HGE in the case studies allows to reduce the CO2 equivalent emissions (CO2e) per car up to 25%, with an opportunity to reduce CO2e/passenger between 40% and 60%, due to the low number of people who normally move in each car.