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Frequently asked questions about the Chariton Valley Biomass Project

EDITOR'S NOTE: The following article was adapted from information prepared by Marty Braster, Chariton Valley Biomass Project coordinator.


November marks the first test firing of coal and switchgrass at Alliant Energy's Ottumwa power plant. There are high hopes for successful burning of what proponents hope will become Iowa's newest cash crop and source of renewable energy: switchgrass.

Cash-crop status for this warm-season grass native to southern Iowa, Panicum virgatum, may be years away, but the Chariton Valley Biomass (CVB) Project has generated a lot of information, interest and hope in recent months. The Leopold Center plays a small but important part by providing the education and outreach funds for this huge effort. The project began nearly a decade ago and now involves scientists from two universities and more than two dozen public agencies and private organizations, nearly 100 cooperating producers, a major utility, plus politicians, conservationists and educators.


Harvest usually begins after the first hard frost in October.

The project is coordinated by the Chariton Valley Resource Conservation and Development (RC&D) in Centerville. Rathbun Lake is located in the middle of the project area, which includes Appanoose, Lucas, Monroe and Wayne counties.

The goal is to produce 35 megawatts of biomass-derived electric power at Alliant Energy's (formerly IES Utilities) generating station in Ottumwa. Replacing five percent of the coal at the power plant would require 200,000 tons of biomass every year and involve as many as 500 farmers.

Researchers at Iowa State University and the University of Iowa are studying ways to improve agronomic practices and environmental benefits associated with producing and using switchgrass and other grasses for biomass. In addition to the fuel possibilities, Prairie Lands Bio-Products, Inc., a group of switchgrass growers in the area, is leading efforts to develop products and markets derived from the plant, such as its use as a filler in resins for plastics, ethanol, fiberboard, mulch and firewood logs.

As might be expected, people who hear about the Chariton Valley Biomass Project have many questions. Here are answers to a few of the most frequently asked questions.

1. What are the CVB project's goals?
The goal of this current phase is to demonstrate the technical feasibility of producing and burning switchgrass with coal to produce electricity. For the past 10 years, utilities in Denmark have been using cereal grain straw, similar to switchgrass, with coal as a fuel to produce energy. Several Danish engineers are technical consultants in the Iowa project.

The long-term goal is that switchgrass and other grasses become commercially viable sources of renewable fuel to co-fire with coal to generate electricity.

2. What about economic feasibility? Can farmers make a profit growing switchgrass?
Farmer profitability is a key issue. Farmers must receive a price greater than their costs of production if they are even going to consider switchgrass. Because biomass production is relatively new, farmers also must receive extra compensation or be assured of a market.

The project includes a study that estimates costs of production. It shows that the two most important factors are yield and land cost. Yield depends on the variety, weather and other environmental factors, and further research should help lower the cost per ton by producing higher yielding varieties.

The estimated cost to produce switchgrass ranged from $48 to $132 per ton, depending on the type of production system used. The cheapest method involved high yields (6 tons per acre) using frost-seeding on grassland. Low yields (1.5 tons per acre) using spring-seeding on cropland resulted in the highest costs of production.

Currently, fossil fuel sources of energy such as coal are much cheaper than switchgrass. But it is difficult to determine how much switchgrass will be worth to replace coal because evaluations do not include environmental benefits such as wildlife enhancement. Other project efforts are directed toward developing markets that offer a premium for electricity generated from biomass, tax credits for the use of biomass as a fuel, and opportunities for landowners to produce biomass on land enrolled in the Conservation Reserve Program (CRP).

3. What other barriers exist?
By-products from the coal-burning process represent major markets, such as coal ash as an additive for cement and concrete. The ash generated during biomass co-firing does not meet specifications for this use. Representatives of the coal fly ash industry are investigating the characteristics of fly ash produced from co-firing biomass to determine its suitability for use in cement and concrete. New specifications also are under review by the U.S. Department of Energy (DOE).

Modifications at power plants that allow biomass co-firing may trigger the need for new air quality permits or costly air pollution control equipment. So far, research shows that using some biomass with coal most likely will reduce the emission of air pollutants at power plants. Alliant Energy is working with the Iowa Department of Natural Resources (DNR) and the U.S. Environmental Protection Agency (EPA) to monitor changes in emissions associated with co-firing biomass.

4. Why was switchgrass selected?
The U.S. DOE and Oak Ridge National Laboratory's Biofuels Feedstock Development Program have identified switchgrass as a model herbaceous energy crop for several reasons. It is native to North America and adapts to a wide range of climates and soils. It has a dense root system that traps nutrients and filters pesticides and herbicides, which protects water supplies. Switchgrass also can be used as forage for livestock and as wildlife habitat.

In terms of its quality as a fuel, switchgrass has a relatively high energy content, comparable to that of wood, and is well-suited to co-firing with coal. Its sulfur and nitrogen contents could result in lower sulfur dioxide and nitrogen oxide emissions than coal, and it is capable of producing high biomass yields with relatively low inputs.

Does switchgrass hold promise for southern Iowa's economy?

5. Isn't switchgrass hard to establish? How is it managed for biomass production?
Cooperating producers and the project field coordinator oversee more than 4,000 acres of switchgrass, and have learned many ways to improve establishment and management of this crop. In general, the use of frost seeding, relatively high rates of pure live seed per acre, and early season weed control have contributed to improved switchgrass establishment. They also hope to show the benefits of combining the production of a corn crop during the initial year of switchgrass.

The use of fertilizer varies with soil, yield and time of harvest, but has commonly included at least 100 pounds of nitrogen per acre and maintenance rates for phosphorus and potassium. Some work has been done to grow legumes with the switchgrass crop as a source of nitrogen.

Harvest typically begins after the first killing frost in October when the grass moisture content is 15 percent or less. Yields can be 30 percent greater at this time than if harvest is delayed until later in the winter or spring.

6. What other biomass is under study?
The biomass project's focus has been on the development of switchgrass and other grasses common in southern Iowa. The relative abundance of cool-season grasses such as reed canarygrass (Phalaris arundinacea), smooth bromegrass (Bromus inermis), orchardgrass (Dactylis glomerata), and tall fescue (Festuca arundinacea) in southern Iowa has generated interest in their use as biomass.

7. Are there other industrial uses for switchgrass?
Project partners are conducting research and development activities in the areas of biomass gasification for energy generation, production of ethanol from lignocellulosic feedstocks, and the blending of biomass with petrochemical resins for use in the manufacture of plastic products.

8. Who is involved in this project? Where do the funds come from?
Currently, more than two dozen public and private organizations have contributed to the Chariton Valley Biomass Project. The project's utility partner is Alliant Energy. Producers are represented by the biomass growers' organization, Prairie Lands Bio-Products.

Research is being conducted by ISU and the University of Iowa. In addition to these partners, principal sources of funds and in-kind contributions for the project include John Deere Works, Iowa DNR, Iowa Division of Soil Conservation, Iowa Energy Center, Iowa Farm Bureau, Oak Ridge National Laboratory, Soil and Water Conservation Districts, T.R. Miles Technical Consultants, U.S. Department of Agriculture, U.S. DOE, Vermeer Manufacturing, and E.L. Woolsey and Associates. The Leopold Center is the primary source of financial support for information and education activities.

9. What else is happening in this project?
The November co-firing was the first of three co-fire test campaigns at the Ottumwa power plant that will continue through 2003. The switchgrass harvested this fall will be used in the 2001 co-fire test. Research related to the agronomic practices and environmental benefits of producing and using switchgrass and other grasses is ongoing.

The project has gained the attention and support of elected officials. In August, the project hosted a regional conference on carbon sequestration.


For more information, write or contact: Chariton Valley RC&D 19229 Highway 5, Centerville, IA 52544 (641) 437-4376; Chariton Valley RC&D Biomass Project.