E5 and E10 contain UP TO 5% and 10% Ethanol. The actual level can vary from delivery to delivery and in reality depends on the relative costs of bioethanol vs refined petrol. It can be even zero, certain brands like Esso currently claiming their super unleaded petrol has zero ethanol despite it being labelled E5.
Ethanol is hygroscopic, petrol is hydrophobic, leading to potential problems with water content.
|