According to a study conducted by the University of California Riverside, Nitrogen Oxides (NOx) emissions could be reduced by up to 90% when using heavy duty vehicles that run on natural gas instead of diesel.
For transportation applications, Natural Gas is a cost effective alternative to traditional fuels. Natural gas consists mostly of methane that when it is combusted is converted to carbon dioxide. The resulting carbon dioxide emissions from burning natural gas are up to 27% less than is produced from burning diesel fuel on an energy equivalent basis.
From the International Maritime Organization (IMO) 2016 study:
“The environmental benefits of using LNG as fuel are significant. Compared to the use of diesel fuel, use of LNG will reduce the NO x emission by approximately 90% on a lean burn gas fuelled engine, and the SOx and particle matters emissions are negligible without the need of any abatement technologies. The CO2 emissions are about 20% lower compared to diesel fuel because of the lower carbon content. However, the overall effect on GHG (Green House Gas) emissions needs further study.”