By Loretta Sorensen
Economic and political roadblocks hinder commercial production of 100% ethanol irrigation engines
There’s plenty of corn for fuel, and irrigation engines designed to run on 100% ethanol have been manufactured for several years. So why are they found in only a handful of corn fields?
There’s no single answer, says Phil High, the Bertrand, Neb., farmer who has been building the engines. The roadblocks to putting the engines on the commercial market include an unsettled economy, fluctuating fossil fuel prices and complex regulations.
"When ethanol plants were being developed here in the 1990s, there were lots of discussions about ethanol applications," High says. "As a farmer, I have a vested interest in seeing ethanol developed. I’m also motivated to cut dependence on foreign oil. When our government began supporting new ethanol and biodiesel enterprises, it seemed there would be research support and funding for projects aimed at developing economical and efficient irrigation engines and fuel blends."
Long road to go. In the course of designing a 100% ethanol–powered irrigation engine, High purchased a license to operate as a fuel dealer, learned that General Motors (GM) was designing a suitable industrial engine and dug into Environmental Protection Agency (EPA) regulations on the use of ethanol as a fuel.
"It’s been a bittersweet experience," he says. "I partnered with others to place about 150 irrigation engines into corn fields as a pilot project. Since July 2008, we’ve run into obstacles that have stalled our project."
The EPA certification process requires engine testing in approved labs, at a cost of $250,000. But the 2008 economic disaster led GM to close down production of the engines that High and his partners were counting on.
"Since GM no longer makes the engine we planned to use, certification has to start over. We don’t have that kind of money," High says.
In addition, plummeting natural gas prices dampened demand for ethanol-burning engines. Prices could rise again, but for now, natural gas is a feasible fuel source.
Fuel evaluation. Loren Isom, technical assistance coordinator at the University of Nebraska’s Industrial Agricultural Products Center in Lincoln, compared dual fuels—ethanol and natural gas—to 100% ethanol for three seasons. The study confirmed that performance and maintenance are not an issue with either kind of fuel.
"Overall, the engine operated very well on 100% fuel ethanol," Isom says. "Adding ethanol to the fuel mix improved the engine’s thermal efficiency and emission profile. The advantages of ethanol—reduced emission profile and a locally produced renewable resource—make it appealing. Data demonstrate that various blends of ethanol can be very efficient."
Engine design and compression ratio greatly affect ethanol efficiency. Because modern engines are designed to operate on fossil fuel, ethanol can be disappointing when used as a direct substitute. To maintain efficiency, some engine modifications might be needed.
"Our analysis isn’t complete," Isom says. "The goal is to evaluate the economics of ethanol versus fossil fuel on a Btu cost per work performed basis, such as dollars per horsepower-hour. Corn growers are very interested in using ethanol for fuel. The challenge is to provide opportunities that fit with fuel delivery infrastructure."
"We know ethanol is a cleaner, environmentally friendly fuel," High says. "Now we need better infrastructure to make it available and better engine design to burn it more efficiently."