By what percentage can a hev reduce emissions as compared to a conventional vehicle

The HEV (Hybrid electric vehicle) reduces the emissions of gas that a produced by a conventional vehicle between 25% and 35%. Even though it is far from perfect and there has to be made improvements so that this percentages become bigger, still the HEV is doing a decent job in reducing the emissions of gaseous pollutants in the air, as well as a better efficiency in fossil fuel consumption.