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AURI is working with farmers, energy suppliers and large consumers to promote and deliver renewable energy sources for a variety of applications, from home heating to municipal power.

Liquids at the fore

Ethanol and biodiesel

Although liquid fuels like ethanol and biodiesel have gained momentum and acceptance, they are not new. Henry Ford designed his first Model T to run on ethanol, and more than a century ago, Rudolf Diesel’s prototype engine was built to run on vegetable oil.

In Minnesota today, 15 ethanol plants generate 367 million gallons per year. Minnesota has more E-85 pumps than any other state: 70 in all. E-85 is an 85 percent ethanol-15 percent gasoline blend that can be burned in flexible fuel vehicles built by Daimler-Chrysler, Ford-Mercury, Isuzu, Mazda and General Motors.

“We are working to inform car dealerships so they can educate consumers about the flexible fuel vehicles. Helping both groups understand the benefits of using E-85 is the challenge,” Simon says.

Current U.S. ethanol production is largely based on grain or starch sources. But advanced technology can produce ethanol from cellulose materials such as corn stover, ag residues and wastes from food and industrial processing. Several companies are investigating this technology as a possible means of ethanol production, says Jack Johnson, head of AURI’s coproducts lab in Waseca.

The U.S. Department of Energy National Biofuels Program is supporting research and development of advanced ethanol technology and has set a goal to have commercial demonstration plants using ag residues in operation by 2005.

EB-diesel, an ethanol-biodiesel blend, is being tested by the automotive technology department at Minnesota State University-Mankato. Biodiesel has advantages over petroleum diesel in areas such as lubricity; ethanol helps reduce emissions. John Deere will begin testing EB-diesel in tractor and combine applications. Simon says the evaluation may carry over into construction equipment and generators.

Solid fuels coming up

Biomass energy

Liquid fuels are far from the only ag-based fuels garnering attention. Solid fuels such as grains, ag processing coproducts, crop residue, even poultry litter and manure are receiving serious consideration as sources for heat and electricity.

“Many solid renewable fuels are more economical to burn than wood, oil or gas,” says AURI engineer Jack Johnson. “Energy prices will affect their attractiveness, but we expect them to become even more viable.”

Several Minnesota power plants, including one in Elk River, now generate heat or electricity by burning wood and biomass such as garbage. Johnson says there is interest among Minnesota municipal power providers and large energy consumers in using renewables such as dry distiller’s grains and corn.

“Companies that currently burn wood are interested in renewables because wood is in short supply and the cost is getting higher,” Johnson says. “In many cases renewables can be burned more economically than other fuels. Coal is still cheaper, but companies burning coal are interested in renewable fuels to help them meet environmental standards.”

When natural gas prices went up last year, several energy consumers approached AURI for help with alternative fuels. While prices fluctuate, Johnson says natural gas costs roughly $5 per million Btu, while corn, for example, costs about $3 per million Btu.

One energy supplier, Hill Wood Products in Cook, Minn., has successfully used ag residues in its facility to provide power to US Steel’s Minntac plant in Mountain Iron, Minn.

While demand is growing, transporting renewable biomass to end users is one challenge preventing large-scale use of biomass energy; costs can become prohibitive.

Harnessing methane

Anaerobic digesters

Anaerobic bacteria gives off methane gas as they digest solids such as manure, municipal sludge or ag processing residue. The methane can be captured by anaerobic digesters, burned for heat or used to generate electricity, while the now-stabilized solid waste can be applied to land.

Digesters are frequently considered in connection with large-scale dairy operations handling large amounts of manure. While the technology is proven, economics play the biggest role in whether or not a digester is viable.

“The technology works,” Johnson says. “If an operation is able to sell electricity back to the utility and receive a favorable rate, it’s much closer to economic feasibility. If they can contract at a ‘green rate’ of 7 or 8 cents per kilowatt-hour, it may work. Others may need to rely on subsidies to make the economics work.” Commingling food processing or municipal wastes with manure in on-farm digesters may also be another option to improve cost-effectiveness.

Turkey power


Benson, Minn. — The nation’s first turkey-litter powered electrical plant is expected to begin construction this spring. In late October, Fibrominn received a vital air quality permit from the Minnesota Pollution Control Agency that cleared the way for construction.

The Fibrominn plant will consume up to 500,000 tons of turkey litter, alfalfa stems and other material to create 50 megawatts of renewable energy annually. Construction of the $100 million facility is expected to take about two years. It will help Excel Energy meet a state mandate to use 125 megawatts of renewable energy.

Environmental regulations governing feedlots and land application of animal waste is expected to increase the demand for Fibrominn’s technology in other locations. Fibrominn’s parent company, Fibrowatt, already operates several poultry-litter powered plants in the United Kingdom.

Corn is cheaper

Biomass stoves

Elk River, Minn. — Bixby Energy Systems of Elk River produces biomass stoves for home heating with an eye towards broader developments including distributed power from renewable sources. Company president Bob Walker says economics, diminishing fossil fuel reserves and energy self-reliance are driving Bixby Energy’s interest in renewable, ag-based fuels.

“The number one reason is that biomass is an economical method of heating,” says Walker. “Corn has been a real cost-effective method of generating heat. Our pellets are as cheap or cheaper. Biomass will play a vital part in supplying the energy we need. It just needs to be put in a form that people can handle.”

Bixby Energy Systems, which Walker hopes to turn into the “Microsoft of biomass,” has worked with AURI to develop clean-burning ag based pellets that deliver a guaranteed amount of heat.

Visions of the future

Fuel cells

Though not yet widely used, fuel cells show promise for the vision of an ag-powered economy. An electrochemical energy conversion device, a fuel cell converts hydrogen into electricity and heat. Much like a battery that can be recharged while power is being drawn, the fuel cell uses hydrogen rather than electricity to recharge.

Minnesota’s corn growers are interested in fuel cells because ethanol has hydrogen in its molecular makeup. Hydrogen atoms are released in the breakdown of ethanol molecules and can be captured to provide fuel for fuel cells.

Fuel cells could be used to power motors, lights, electrical appliances, cars, buses and even provide power for a home.

From chicken fat to beef tallow

Recycled grease for boiler fuel

Plant biomass is not the only stuff of renewable fuels. Yellow and white greases, beef tallow and chicken fat have been evaluated for their boiler fuel potential by the national Fats and Proteins Research Foundation, which is investingating new uses for rendered fat. The study, completed June 2002 by the University of Georgia, shows that combustion emissions and the Btu values of fats and oils compare favorably to No. 2 fuel oil.

An FPRF member, Central Bi-Products of Redwood Falls and Long Prairie, Minn., conducted a similar study the winter of 2000. The rendering company compared the Btu values of recycled grease and natural gas; its findings were consistent with the University of Georgia study. Chuck Neece, Central Bi-Products research and development director, says the results give credibility to this alternative fuels source.

“As the price of natural gas goes up, recycled greases become a viable fuel source,” Neece says. “Particularly in stationary equipment, the recycled greases become very economical to use, whether in a generator or boiler.”

Neece says sulfur compound emissions are lower in recycled grease than No. 2 fuel oil, and the renewable material has good potential as a low-sulfur fuel.

Elsewhere in biofuels and energy

Gambling on biodiesel

The Clark County school district in Las Vegas recently switched over a thousand school buses to biodiesel — making it the world’s largest school bus fleet to run on biodiesel.

Several independent studies indicate that the more than 25 million children who ride school buses face up to eight times greater exposure to toxic diesel exhaust than if they walked. Biodiesel significantly reduces the harmful emissions that threaten human health.

Las Vegas-based Biodiesel Industries collects French fry oil from casinos to make biodiesel that fuels the buses.

Source: National Biodiesel Board, 1-800-841-5849.

Flying colors

Biodiesel is the only alternative fuel to pass the rigorous health-effects testing of the Clean Air Act. Two years of independent studies show that, compared to diesel fuel, biodiesel reduces carcinogenic emissions by 75 to 90 percent, is low in toxicity, readily biodegradable and free of sulfur.

Source: National Biodiesel Board, 1-800-841-5849,

Ditching MTBE

Exxon Mobil, the world’s largest oil company, is switching from MTBE to ethanol in its California gasoline early this year. Ethanol will replace MTBE for four of California’s five major oil refiners. And Phillips Petroleum Co. has become the first gasoline retailer in California to offer MTBE-free gasoline year-round at all its 1,500 outlets.

Source: Renewable Fuels Association,

Net energy yield

A new USDA study confirms the energy efficiency of ethanol. “The Energy Balance of Corn Ethanol: An Update” concludes that ethanol production is energy efficient because it yields 34 percent more energy than is used in growing, harvesting and distilling corn.

Source: Report is available at

Spinning straw into fuel

The Rice Straw Cooperative and the town of Gridley, Calif. have secured more than $100,000 in state and federal grants to build a facility to make ethanol from rice straw. The goal is to have a plant up and running by July.

Source: Progressive Farmer, September 2002.

Breaking records

The ethanol industry is expected to produce a record 2.7 billion gallons in 2003. Last year, 66 ethanol plants produced more than 2.5 billion gallons annually. Three more plants recently came on line and eight more are under construction.

Source: Renewable Fuels Association,

Ethanol plants pop up

Farmer-owners of KAAPA Ethanol, LLC, have begun building an ethanol plant near Axtell, Neb. KAAPA is one of two new ethanol plants currently under construction in Nebraska, which now has seven plants.

In South Dakota, Progressive Energies, LLC in Platte, and Glacial Lakes Energy, LLC in Watertown recently began constructing ethanol plants.Adkins Energy LLC, Lena, Ill. has completed the first farmer-owned ethanol plant in Illinois; it includes a co-generation facility to produce steam and electricity for the plant.

In Wisconsin, Badger State Ethanol, LLC in Monroe began ethanol production this fall.

Source: Renewable Fuels Association,

To ethanol or not

With 70 to 80 new U.S. ethanol plants now planned or begun, concern is growing that the industry could hit over-capacity in three to five years. Kansas State University ag economist David Coltrain has developed an “Ethanol Pre-Feasibility Evaluator,” with a downloadable spreadsheet, to help potential ethanol investors.

Source: Successful Farming, October 2002. Report at or contact David Coltrain, (785) 532-1523,

Clean energy in farm bill

The Clean Energy Development Provision, or Title IX of the Farm Security and Rural Investment Act of 2002, provides $115 million to assist farmers and ranchers in developing renewable energy and making energy efficiency improvements on their farms. It also designates $290 million for biomass energy research and biodiesel education and would continue subsidizing, under the Commodity Credit Corp. program, biodiesel and ethanol production.

Another amendment to the rural development legislation makes wind power, other renewable energy sources and energy efficiency eligible for hundreds of millions of dollars of funding.

Source: The Land, Southeastern Edition, September 27, 2002.