Take a second look, Brazil study helps prove the value of mid-level ethanol blends

Source: Kim Trinchet, Urban Air Initative • Posted: Friday, May 9, 2014

(Colwich, Kan. – May 7,2014) – A recent study titled Reduction in local ozone levels in urban Sao Paulo due to a shift from ethanol to gasoline use is attracting a lot of attention. This study claims a 20% reduction in ozone when drivers in Brazil switched from ethanol to gasoline. However, it’s important to point out that the gasoline used during the time of this study is actually a blend of 25 percent ethanol. This helps prove that mid-level ethanol blends are a benefit for consumers and emissions.

Both Brazil and the U.S. began introducing ethanol into the fuel market for the purpose of reducing their dependence on imported oil. However, in the 1980’s both countries chose different pathways to get to where we are today.

The U.S. has two ethanol blended fuels available. The most common is E10 (10 percent ethanol, 90 percent gasoline) which can be used in all vehicles. The other is E85 (85 percent ethanol, 15 percent gasoline) which can only be used in flex fueled vehicles made for the U.S.

Brazil also has two fuels, E25 (25 percent ethanol, 75 percent gasoline) and Ethanol (95 percent ethanol, 5 percent water). Most vehicles sold in Brazil are flex fueled and can run on either blend, drivers choose their fuel based on price.

Ozone emissions are highest with pure gasoline and also Ethanol with water. Emissions are reduced when you add ethanol to gasoline, until you reach a 50/50 blend of ethanol and gasoline. Emissions benefits are diminished when you go above an E85 blend of ethanol. This is why Brazil saw ozone emissions improve when drivers started using E25 instead of Ethanol with water.

With 70 percent of Brazilian fuel being E25 during the timeframe of this study, Brazil demonstrated it has one of the cleanest burning fuels available. If the U.S. would allow higher blends, for example E30, there would be significant reduction in ozone and toxic emissions from aromatics in gasoline.

We urge the EPA to look into the details of this study. If ethanol blends were increased in the U.S., the public would benefit from air quality improvements and they would pay less at the pump.