c ents , ▁and ▁B 2 0 ▁bl ends ▁were ▁the ▁same ▁as ▁pet rod ies el . ▁However , ▁as ▁part ▁of ▁a ▁dram atic ▁shift ▁in ▁dies el ▁pr icing , ▁by ▁July ▁ 2 0 0 9 , ▁the ▁US ▁DO E ▁was ▁reporting ▁average ▁costs ▁of ▁B 2 0 ▁ 1 5   c ents ▁per ▁gall on ▁higher ▁than ▁pet role um ▁dies el ▁($ 2 . 6 9 / gal ▁vs . ▁$ 2 . 5 4 / gal ). ▁B 9 9 ▁and ▁B 1 0 0 ▁generally ▁cost ▁more ▁than ▁pet rod ies el ▁except ▁where ▁local ▁govern ments ▁provide ▁a ▁tax ▁in cent ive ▁or ▁subs id y . ▁In ▁the ▁month ▁of ▁October ▁ 2 0 1 6 , ▁B iod ies el ▁( B 2 0 ) ▁was ▁ 2 ▁c ents ▁lower / g all on ▁than ▁pet rod ies el . ▁ ▁Production ▁ ▁B iod ies el ▁is ▁commonly ▁produced ▁by ▁the ▁trans ester ification ▁of ▁the ▁veget able ▁oil ▁or ▁animal ▁fat ▁feed stock , ▁and ▁other ▁non - ed ible ▁raw ▁materials ▁such ▁as ▁f ry ing ▁oil , ▁etc . ▁There ▁are ▁several ▁methods ▁for ▁carrying ▁out ▁this ▁trans ester ification ▁reaction ▁including ▁the ▁common ▁batch ▁process , ▁heter ogeneous ▁catal yst s , ▁super crit ical ▁processes , ▁ul tr ason ic ▁methods , ▁and ▁even ▁mic row ave ▁methods . ▁ ▁Chem ically , ▁trans ester ified ▁b iod ies el ▁compr ises ▁a