I just read recently that California is going to phase out MTBE gas additive and switch to ethanol based fuel. Does anyone know what effects ethanol fuel has on fuel mileage, power and other performance characteristics of an engine? I'm hoping that the new fuel might help increase gas mileage but my skeptical side says it probably will decrease mileage (more $$ for the farmers/oil companies - why else would BP and Union 76 switch to ethanol over a year earlier than they are required to?).

 

Ethanol is bad, just like MTBE. The reason MTBE is being phased out is because the stuff is nasty when it gets into the groundwater ( I deal with this stuff daily - environmental engineer). MTBE does not break down in water over time. 1-gallon of MTBE will make over 1 million gallons of water taste funny. Ethanol is a vegetable based oil. It doesn't burn well and it is a bit corrosive. Nearly every automaker suggest not using the stuff. Try to only use stations that don't use the stuff, if you can.

I've always found it funny that the tree huggers (and farmers too) in Cali have pushed hard for MTBE/Ethanol in gasoline in an effort to reduce smog. Data suggests that MTBE/ethanol reduce emmissions by 3-5%, but hurt gas mileage by 6-10%. You do the math. Which is better? Slightly better emissions from cars or increased fuel comsumption from poor burning fuel (take into account the extra energy needed to extract larger amounts of consumed fuels). Don't get me started about the environmental disaster MTBE has caused in our groundwater.



Dave