An advantage of fuel cells over biogas/biodiesel is that the former only produce water vapour while the latter, due to the fact that they use ambient air for co

An advantage of fuel cells over biogas/biodiesel is that the former only produce water vapour while the latter, due to the fact that they use ambient air for combustion which contains 78% nitrogen also produce nitrogen oxides which in turn lead to smog, acidification, ozone and fine particle production.