ed ▁from ▁chemical ▁re actions . ▁The ▁difference ▁in ▁fuel ▁cells ▁when ▁compared ▁to ▁batter ies ▁is ▁their ▁ability ▁to ▁be ▁power ed ▁by ▁the ▁constant ▁flow ▁of ▁hydro gen ▁found ▁in ▁the ▁atmosphere . ▁Furthermore , ▁they ▁produce ▁only ▁water ▁as ▁a ▁by - product , ▁and ▁are ▁virt ually ▁silent . ▁The ▁down side ▁of ▁hydro gen ▁power ed ▁fuel ▁cells ▁is ▁the ▁high ▁cost ▁and ▁d angers ▁of ▁storing ▁highly ▁comb ust ible ▁hydro gen ▁under ▁pressure . ▁ ▁One ▁way ▁new ▁process ors ▁can ▁overcome ▁the ▁d angers ▁of ▁transport ing ▁hydro gen ▁is ▁to ▁produce ▁it ▁as ▁necessary . ▁The ▁mic r ore act ors ▁can ▁be ▁joined ▁to ▁create ▁a ▁system ▁that ▁he ats ▁the ▁hydro car bon ▁under ▁high ▁pressure ▁to ▁generate ▁hydro gen ▁gas ▁and ▁carbon ▁dio x ide , ▁a ▁process ▁called ▁steam ▁reform ing . ▁This ▁produces ▁up ▁to ▁ 1 6 0 ▁gall ons ▁of ▁hydro gen / min ute ▁and ▁gives ▁the ▁potential ▁of ▁power ing ▁hydro gen ▁ref uel ing ▁stations , ▁or ▁even ▁an ▁on - board ▁hydro gen ▁fuel ▁source ▁for ▁hydro gen ▁cell ▁vehicles . ▁Im plementation ▁into ▁cars ▁would ▁allow ▁energy - rich ▁fu els , ▁such ▁as ▁b iod ies el , ▁to ▁be ▁transferred ▁to ▁kin etic ▁energy ▁while ▁avoid ing ▁comb ust ion ▁and ▁poll ut ant ▁by products . ▁The ▁hand - s ized ▁square ▁piece ▁of ▁metal ▁contains ▁micro scop ic ▁channels ▁with ▁catal yt ic ▁sites , ▁which ▁continu ously