A New Frontier for Agriculture

By Karl F. Ohm

Developing new uses for agricultural commodities offers a renewable and sustainable means to diversify the rural economy.

The U.S. Department of Energy (DOE) estimates that by 2005, the United States will likely be importing nearly 60 percent of its transportation fuel. In 1998, the U.S. spent nearly $52 billion on imported oil — or more than $1.7 trillion since 1970. Two-thirds of the oil is used for transportation.

Against this backdrop and with the recent power blackouts in California, it’s no surprise that energy policy has once again emerged as a critical, national policy issue and one that holds deep ramifications for the economy, environment, and even national security.

For some groups, the mission is clear: Agriculture offers the means to help society unhook itself from its strong dependence on petroleum.

One major group touting this message is the New Uses Council. Since its formation in 1990, the Council has been dedicated to expanding the development and commercialization of new industrial, energy and non-food uses of renewable agricultural products made from both traditional commodities and new crops.

“Agriculture is sure to become that necessary bridge that takes us from an economy dependent on finite resources over to an economy fueled by renewable resources,” says Erwin “Bud” Sholts, chair of the New Uses Council and former director of the Agriculture Development and Diversification program at the Wisconsin Department of Agriculture, Trade and Consumer Protection.

Another group focused on how agriculture can produce a bio-based economy is the Midwest Consortium for Sustainable Bio-based Products and Bio-energy. Randy Woodson, director of Purdue’s Agricultural Research Program describes the consortium as a multi-disciplinary effort aimed at creating facilities, technology, training and expertise for establishing and maintaining a bio-based industry in the Midwest.

Public funding and private capital are flowing into alternative energy projects, and some of the most promising are:

Biomass
There are more than 350 biomass power plants in the U.S. generating more than 7,500 megawatts of electricity – enough power to meet the needs of several million homes, according to the DOE. By 2020, the DOE estimates that 30,000 megawatts of biomass power could be installed. 40 percent of the biomass feedstocks (fuel) would be supplied from more than 10 million acres of energy crops (i.e., switchgrass) and the remainder from biomass residues.

Large round bales of switchgrass (a hardy and drought-tolerant native prairie grass that once fed buffalo herds), for example, have been tested by Madison Gas and Electric and by utilities in Iowa to replace or supplement coal. A 750 pound round bale of switchgrass contains the energy equivalent of 490 pounds of coal or 41 gallons of gasoline or fuel oil.

More work needs to be done on both production and utilization of switchgrass, however, to make it more competitive. Some additional studies include:

In mid-January, the Ottumwa Generating Plant, a 650-megawatt, coal-fired facility near Chillicothe in southeastern Iowa, was retrofitted to burn switchgrass along with its primary fuel as part of a test project. The power plant, owned by Alliant Energy, burns coal to generate electricity for about 200,000 homes. It started burning switchgrass mixed with coal in late November last year. By the end of January 2001, the plant had burned 4,000 tons of the thick-stemmed, native perennial that is easily grown, harvested and baled in southern Iowa. Further tests during the next few years will measure the impact of burning grass on the boiler’s efficiency as another 35,000 tons of switchgrass is mixed with coal.

Test plots of switchgrass at Auburn University in Alabama have produced up to 15 tons of dry biomass per acre, and five-year yields average 11.5 tons — enough to make 1,150 gallons of ethanol per acre each year.
Researchers at Oklahoma State University/ Stillwater are examining switchgrass as a feedstock to make bio-fuel. They believe that, with the right infrastructure, ethanol could be produced from switchgrass more efficiently than from corn.

Bio-diesel Fuel
Another emerging alternative source of energy is bio-diesel fuel. It can be derived from a variety of agricultural commodities, such as soybean oil, canola (rapeseed) oil, sunflower oil, tallow, and even waste grease from fast-food restaurants.

In Wisconsin, interest in developing a new form of bio-diesel fuel grew in 1998 when the Wisconsin Business Innovation Corporation helped form the Badger Oil Company. The company uses “cold press technology” to produce biodegradable fuel lubricants and oils from sunflower, canola and soybean seeds. This cold press technology comes from Germany, and Badger Oil Company is currently working with two German companies and a subsidiary, which produce the seed crushing equipment and special biodegradable additives. These special additives are used in the vegetable seed oils to produce bio-diesel fuel or industrial lubricants.

Energy from Super Enzymes
Larry Walker, Cornell professor of agricultural and biological engineering, and his students are using enzymes to break down solid biomass waste into a renewable energy form. Walker says there is sufficient biomass waste available to supply all of the organic chemicals that are consumed annually in the U.S. and still have enough waste left over to convert into transportation fuel.

Plant biomass is chemically diverse, and it must be separated and then converted into desired products. The challenge, he explains, is to develop industries proficient in using this raw material and to develop more cost-effective enzymatic and microbial processes that convert these materials into industrial chemicals and energy.

About 279 million metric tons of plant waste are generated in the U.S. annually from industrial, commercial and agricultural production. The key to using this resource lies in employing enzymes to break down the woody, fibrous part of the material into fermentable sugars.

Walker and his students are studying how enzymes from thermophilic (heat-loving) bacteria break down the cellulose in plant waste. The bacteria produce six enzymes, called cellulase which attack the biomass through a process called hydrolysis. This allows the enzymes to process the cellulose into fermentable sugars, permitting scientists to produce fuel or industrial chemicals.

Not only do plants represent a renewable source of organic compounds but there also is considerable organic waste produced that could be a carbon source for bio-industries.

For example, corn stover (much of it used as fodder) accounts for 100 million metric tons of biomass waste produced annually in the U.S. Newsprint biomass waste accounts for 11.2 million metric tons. Urban tree residue — leaves, Christmas trees and broken branches — accounts for 38 million metric tons.

Plastics from Plants
Scientists have found a gene that allows plants to package and store materials in their cells — a discovery that may open the door to producing new types of plastics from plant materials.
Clint Chapple, professor of biochemistry at Purdue University, and Knut Meyer of DuPont and Co., have cloned a gene from the common laboratory plant Arabadopsis that will allow materials to produce plastics in crops without damaging the plant’s health.

Crop plants such as corn or soybeans hold the potential to create plants that provide the starting materials to make the plastics we already have and to make new plastics with never-before-seen properties, Chapple says.

The Thames’ Research Group at The University of Southern Mississippi’s Polymer Science Department, based in Hattiesburg, is investigating the potential of both virgin and dehydrated lesquerella oil (LO) in a number of coatings formulations. LO is a natural product that can be added to coatings and foams to increase flexibility and resistance to solvents, water, and corrosion.

Lesquerella fendleri is a winter annual plant native to the Southwest but capable of being cultivated throughout the southern half of the U.S. The plant’s seed yields more than 25% (by weight) of oil compositionally similar to and in some ways structurally superior to castor oil, a strategic material imported in its entirety. Castor oil is currently the only available commercial source of hydroxy acids used in the production of coatings, lubricants, plastics, and a host of other products.

A biodegradable corn-based shrink wrap would create a new market for corn and replace some petroleum-based plastics. Some Illinois cattle are eating dry hay — wrapper and all — thanks to University of Illinois researchers who have developed a corn-based shrink-wrap. The wrap is made from zein, a byproduct of ethanol processing. It is biodegradable and digestible — good for the cattle, good for the soil and good for the environment.

Protecting round bales from the elements is the first test of the new material. Eventually, the corn-based wrap may provide an alternative to petroleum-based plastics used in many industries, especially warehouses, where shrink-wrap is used to store merchandise or supplies on pallets for a short time.

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