What’s Better, Ethanol or Gas?
Millions of clean-running alternative fuel vehicles are plying American roads, ready and waiting to fill their tanks with ethanol fuel. These are flexible-fuel vehicles, or FFVs, marketed by Ford, General Motors, DaimlerChrysler, Isuzu, Mazda, and Mercedes-Benz since the late 1990s. FFVs are so-named because they can operate seamlessly on any mixture of E85 (a blend of 85 percent ethanol and 15 percent unleaded gasoline) or straight unleaded gasoline from the same tank.
Ethanol, or ethyl alcohol, is a clean burning fuel typically produced from corn, although other grains like wheat or barley can also be used. These feedstocks are abundantly available in this country. Besides its advantages as a renewable and domestically available biofuel, ethanol combustion in engines also results in modest reductions of harmful hydrocarbon and benzene emissions, as well as reduced carbon dioxide, a greenhouse gas.
Hmmm… domestically produced by American farmers and producers, lower emissions, and a huge number of vehicles with tanks a-waiting. So why is there such a monumental disconnect that finds millions of FFVs on the highway and only about 175 stations nationwide where drivers can fill up on E85?
This dichotomy is good example of what can occur when technology outpaces society’s ability to apply its use, in this case primarily due to economics and, unfortunately, politics. It’s also an example of how government incentives and subsidies can have unintended consequences. Lessons learned from the FFV experience should be examined and applied as the nation embarks on a path that will find us potentially using a much more technically challenging and expensive alternative fuel: hydrogen.
The dilemma can be traced directly to the Alternative Motor Fuels Act (AMFA) passed by Congress in 1988, a law that gives automakers incentives to develop and market vehicles that use fuels other than gasoline. Manufacturers can receive a credit of up to 1.2 miles-per-gallon for each FFV produced that can be applied toward meeting their Corporate Average Fuel Economy (CAFE) requirements. Unfortunately, there is no corresponding incentive to encourage development of a refueling infrastructure, which brings us to the nearly nonexistent E85 refueling infrastructure today.
Establishing an E85 infrastructure presents a significantly larger challenge than getting engines to run well on E85. Since alcohol fuels like ethanol cannot be moved readily through existing petroleum distribution pipelines, it must be transported by barge, rail, or truck. Contrasting this, modifying an engine to run on E85 is not that difficult, requiring a fuel sensor for detecting the real-time ratio of ethanol to gasoline being supplied to the engine at any given point in time and optimizing engine and fuel settings for this mixture. Items like stainless steel fuel tanks, Teflon-lined fuel lines, and modified injectors must also be used to ensure compatibility with ethanol since it’s a much more corrosive fuel than gasoline.
From a vehicle standpoint, the AMFA incentive is a resounding success. Manufacturers driven by the additional CAFE credits made more than a million FFVs last year and expect to produce twice as many in 2004.
Popular models that can run on gasoline or E85 range from the Ford Explorer and Chevrolet Silverado to the Dodge Stratus and Mercedes-Benz C320. These vehicles are available in many, but not all, states, so check with your local dealer or your dealer’s fleet department to confirm availability in your area.
Still, while the vehicle end is a success, all this has not accomplished the AMFA’s primary intended goal of reducing the nation’s dependence on imported oil, not to mention significantly decreasing C02 emissions. According to the National Highway Traffic Safety Administration (NHTSA), extending these credits without expanding the availability of E85 actually increases petroleum consumption and greenhouse gas emissions. That’s because FFVs operating almost entirely on gasoline effectively decrease the CAFE for this FFV fleet by about 1.2 mpg. The credits given for the unused ethanol equates to somewhere between 20 to 56 million additional barrels of oil used annually.
Several solutions to this so-called CAFE loophole have been proposed. One calls for Congress to amend the existing AMFA law to only allow CAFE credits when automakers can certify that their AFVs actually use the alternative fuel. In effect, though, this would penalize the auto industry unfairly since automakers have done their part in developing and marketing FFVs. This strategy could potentially sour automakers’ interest in all AFVs and drastically reduce future investment in other fuel alternatives including hydrogen.