What are the main methods used by car manufacturers to reduce emissions in their ICE cars besides trying to lower the amount of fuel the engine uses?

Thank you for your question ! I ' m glad you ' re interested in learning about ways to reduce em issions from internal comb ust ion engine ( ICE ) cars . There are several methods that car manufact ur ers use to reduce em issions besides lower ing fuel consumption . Here are some of the main methods : \n 1 . Ex ha ust Gas Rec ir cul ation ( EG R ): This method involves rec ir cul ating a portion of the exhaust gas back into the engine cyl ind ers to reduce the amount of nit ro gen ox ides ( NO x ) em itted . \n 2 . Catal yt ic Con ver ters : These devices use catal yst s to convert harm ful poll ut ants like carbon mon ox ide ( CO ), hydro car b ons ( HC ), and NO x into less harm ful subst ances like carbon dio x ide ( CO 2 ), water ( H 2 O ), and nit ro gen ( N 2 ). \n 3 . Part ic ulate Fil ters : These filters use a combination of chemical re actions and physical processes to capture and remove partic ulate matter ( PM ) from the exhaust gas . \n 4 . Direct In jection of F uel : Direct fuel injection allows for more precise control over the amount of fuel inject ed into the engine , which can reduce em issions by minim izing the amount of fuel was ted through ev ap oration and impro ving comb ust ion efficiency . \n 5 . Hom ogeneous Char ge Com pression Ign ition ( H CC I ): This is a comb ust ion method that uses a combination of spark ign ition and compression ign ition to improve fuel efficiency and reduce em issions . \n 6 . Tur bo charg ing : Tur bo charg ing uses the exhaust g ases to drive a tur bine , which compress es the air entering the engine , allowing for a greater amount of air and fuel to be burn ed per cycle , resulting in increased power and efficiency while reducing em issions . \n 7 . Hy brid ization : Hy brid vehicles use a combination of an I CE and an electric motor to improve fuel efficiency and reduce em issions . The electric motor can assist the I CE during low - load conditions , reducing the amount of fuel consum ed and em issions produced . \n 8 . Altern ative Fu els : Some car manufact ur ers are expl oring the use of alternative fu els like bio fu els , hydro gen fuel cells , or com pressed natural gas ( C NG ) to reduce em issions . \n \n It ' s important to note that these methods can vary depending on the type of engine and vehicle , and some may be more effective than others . Additionally , some methods may have trade - offs in terms of fuel efficiency or performance . \n I hope this information helps ! If you have any further questions , please feel free to ask . </s>