Emission of Nitrogen Oxides - NOx - with combustion of fuels like oil, coal, propane and more.
Emission of Nitrogen Oxides - NOx - when burning different types of fuels:
(10-3 kgNOx / kgfuel)
|Wood, Birch 20% moisture content||0.7|
1) note that the emission varies widely depending on application temperatures and air/fuel ratios. In general - higher combustion temperature and higher air/fuel ratios increases NOx emissions.
2) zero emission for hydrogen is a theoretically value. In practice hydrogen burned in air produces more NOx than natural gas due to the high flame speed
3) catalytic systems common on most modern vehicles reduces NOx
NOx emissions contributes to eutrophication, acidification and the formation of ground-level ozone.