I was reading an article re Ethanol in Fuel
and the following was interesting.
"Adding 10% ethanol to gasoline will lower driving costs, but not necessarily. Ethanol contains less heat energy than gasoline but this reduction in power is minimal compared to the decrease in fuel economy because of the additional oxygen released from the ethanol in the combustion chamber. Adding oxygen in the fuel improves combustion efficiency, but on modern fuel injected cars, this extra oxygen passes out with the exhaust gases and the oxygen sensor detects it. This is reported to the fuel injection computer which calculates the engine is operating in a lean fuel mixture state and add more fuel to compensate. Fuel mileage drops. "
E10 in Australia
If I undertand it correctly E10 would give about 2.8% worse Fuel Economy and in the Australian Context would cost 7.8% more to buy E10 based fuels which would be payed by the coonsumer directly or through subsidies to the Ethanol industry.........
However a big worry, as outlined in the original article, is excessive water in your fuel .
"Ethanol acts like gas line anti-freeze. Adding additional gas line anti-freeze won't be necessary in winter, but keeping the water out of the fuel becomes very important. When a 10% ethanol blend is contaminated with over .5% water, the ethanol and water mixture will separate from the gasoline and fall to the bottom of the gas tank. This can cause the vehicle to run poorly or stall. The water can come from condensation inside the tank, bulk storage tanks or even your local filling station. Normally, any water sits at the bottom of the filling station tanks and doesn't mix with the gasoline, but when 10% alcohol is added, the water and alcohol do mix with the gasoline. The water ends up in your tank. Filling your vehicle at carefully monitored filling stations could be important. "
Another Article by Caltex
may be of Interest as well
However obviously the concern is no labelling up to E5 which the Government
has currently reproposed.