The emission focus has moved from harmful-to-health pollutants (CO, HCs, NOx, SOx, particulates, NH3) to green house gases (GHG).
Light-duty cars and other applications are moving fast electric or hybrids, but liquid fuels needed in heavy-duty applications
Pollutant limits will remain the same or tightened in near future
Harmonization: Emission limits independent on fuel or engine type (multi-fuel engines)
Green fuels can decrease (NOx, SOx, particulates, other poisons) or increase (NOx, CH4 , N2O, NH3) pollutant emissions
Green electricity has a key role in the move to carbon-free fuels and energy