Most agricultural tractors rely on petroleum-based diesel fuel, even as a significant share of the corn harvested in the United States is used to produce ethanol. Purdue University, John Deere, Cummins and a consortium of biofuel producers are researching whether ethanol can become a viable fuel component for agricultural diesel engines.
The project combines engine development, fuel research and business considerations to determine how tractors could operate on ethanol-biodiesel blends. Researchers are working toward engines capable of using the blends, fuel that is readily available and a customer base willing to adopt the technology.
The effort builds on the use of ethanol in passenger vehicles, where flex-fuel technology emerged in the 1990s and ethanol was gradually introduced into gasoline blends. Researchers see similar potential for agricultural equipment, including increased demand for corn, lower carbon emissions and greater domestic fuel security.
Petroleum-based diesel depends on ingredients sourced from other countries, creating potential exposure to international disruptions and fuel price volatility. Increasing the use of domestically produced biofuels could reduce reliance on overseas fuel sources while providing additional economic opportunities for farmers.
Researchers say the technology still faces significant challenges. Current diesel engines require specialized sensors and other infrastructure to adjust to fuel mixtures containing high levels of ethanol. The long-term goal is to develop engines that can operate with diesel, biodiesel and ethanol-biodiesel blends without requiring additional hardware or requiring operators to know the precise fuel blend being used.
Even the ability to use a 10% ethanol mixture in diesel engines could significantly expand opportunities for both the diesel engine and biofuel industries.
The researchers envision the technology being available for new engines as well as through aftermarket retrofit kits. Ideally, new engines would be fuel-agnostic, allowing operators to choose among diesel, biodiesel and biodiesel-ethanol blends based on availability and economics.
That flexibility could help farmers and heavy equipment operators manage fuel costs by selecting the most economical fuel option at a given time. The researchers also hope older diesel tractors eventually could be retrofitted to use multiple fuel types.
The project relies on collaboration among universities, engine manufacturers and biofuel producers rather than development by a single company. Researchers say broad industry participation could help ensure that advances in engine technology are widely adopted and expand the market for biofuels.
Purdue's combination of engineering and agricultural expertise also provides a foundation for addressing the technical and agricultural aspects of the project. Researchers acknowledge that widespread adoption could take years, but they see fuel flexibility in agricultural equipment as a potential long-term benefit for farmers, biofuel producers and the broader energy sector.
Source: Purdue University, "Purdue Biofuels Consortium to bring biodiesel and ethanol blends to diesel engines"