As per we know , petroleum is  degrading at  a great pace , 65 % percent of vehicles run on  petroleum. one thing is that it is a non -renewable resource. it cannot be obtained further by any means .
although CNG and Hydrogen is another substitute , but due to less availability , it cannot be used for a long time . .
In INDIA CNG is a better substitute  but due to its less availability , and costly CNG kit ,it cannot be accepted as a better fuel source, it occupies more space, it cannot be used on  two wheeler .
So ,here ALCOHOL can be a best alternative resource ,because it is obtained by waste(sugarcane ,cotton,rice etc. )
Brazilian vehicles runs on alcohol fuel (E-85) .
ETHANOL is the best fuel i.e., E85 in which 85% is ethanol and 15% is gasoline .
INDIAN govt . should also focus in this subject, as alcohol production is abundant in INDIA .