Energy transition in road transportation for developing countries is usually related with the implementation of the best available technologies, the improvement of energy efficiency, and the use of fuels with less carbon content than diesel and gasoline. One the most promoted alternative fuel worldwide has been natural gas, and most recently, hydrogen and ammonia are playing important roles like energy transition fuels and carriers. This study presents an experimental research of a Diesel Euro-4 vehicle N2-category tested on a chassis dynamometer for stationary and transient operations according to WLTP protocol, by using two dual-fueling strategies with natural gas (NG) and hydrogen (
). The experimental phase was carried out in Medelín-Colombia, vehicle dynamic was determined by applying coast-down methodology at representative conditions. Stationary tests were performed to show the effect of vehicle speed and transmission gear on the engine load and pollutants. Gaseous and particles emissions, as well as fuel consumption and energy efficiency were measured for both dual-fueling systems and for conventional diesel operation. Compared with diesel mode, dual-NG operation increased CO emissions by a factor of 3.1, HC emissions by 6.7, and PM2.5 emissions by 10.96%. Furthermore, NOx were reduced in 44.32% and PN2.5 emissions in 3.53%, whereas traveled distance per gallon was extended in 23.35% and overall energy intensity was increased in 41.42%. Dual-
operation reduced in 22.42% and 12.33% the THC and PM2.5 emissions respectively, when compared with diesel mode. The PN2.5 were reduced in 60.83%, whereas NOx,
, and overall energy tensity were increased in 11.10%, 3.97%, and 2.47% respectively, for WLTC cycle Class 1. The results obtained enable a greater understanding of the effects of dual-fuel operation on the energy efficiency and pollutant emissions of CI engines, at representative transient conditions for cities located at high altitude above sea level, and the best available technologies for road load transportation in developing countries.
