Diesel

Diesel-engined cars have long been popular in Europe with the first models being introduced in the 1930s by Mercedes Benz and Citroen. The main benefit of diesel engines is a 50% fuel burn efficiency compared with 27% in the best gasoline engines. A down-side of the Diesel engine is that better filters are required to reduce the presence in the exhaust gases of fine soot particulates called diesel particulate matter. Manufacturers are now starting to fit[when?] diesel particulate filters filters to remove the soot. Many diesel-powered cars can run with little or no modifications on 100% biodiesel and combinations of other organic oils.