Feedstock System Development

Biomass beginning

Knowing where you are is the best place to begin any journey. To determine that starting point, WSU Professor Shulin Chen and research associate Craig Frear, both based in the Department of Biological Systems Engineering, worked with the Washington State Department of Ecology to develop a comprehensive inventory of biomass produced in the state and analyze the conversion technologies necessary to use it for energy production. The project includes four parts: 1) characterizing 42 feedstocks according to their chemical properties such as carbon, protein, and fiber; 2) identifying and grouping the feedstocks; 3) simulating the potential conversion processes such as thermal-chemical conversion, anaerobic digestion, and ethanol production on individual feedstock or their combinations; and 4) economic analysis of the processes from feedstock collection and distribution to energy production. The inventory published in June 2007.

Lovely lipids

Understanding the fundamentals of how plants grow is enabling Regents Professor John Browse, a researcher in the WSU Institute for Biological Chemistry, to double the yield of derivative lipids (fats) in plant oils. Browse and his team’s identification and cloning of the related desaturase gene in Arabidopsis, an easy-to-grow plant with a fully-sequenced genome, led to the bioengineering of other plants to produce more sustainable alternatives to fossil fuels and petrochemicals—i.e., biodiesel and precursors to biodegradable plastics and resins.

Bulking up yields

Crops on steroids could be a source of biofuels and other bioproducts in the future.

Michael Neff, assistant professor of crop biotechnology in the Department of Crop and Soil Sciences, is studying how plants regulate their own steroid hormone levels. His work has the potential to dramatically increase yields in a variety of crop plants, including those used for biofuels and bioproducts.

“One of our long-term goals is to understand the biology of how particular enzymes inactivate growth-promoting hormones in crop plants to manipulate their size and stature and increase yields,” said Neff.

Neff is using Arabidopsis to better understand how plants, in general, use light as a source of information, and how the signaling pathways activated by light interact with plant hormone pathways to influence plant height and heft.

“These brassinosteroids have the potential to increase yield in crop plants because they have the same structure in all plants,” Neff said. “If we identify an enzyme that inactivates the steroid, we can target that enzyme, remove it, and allow the increased steroid levels to help the plant bulk up in size.”

Neff noted the groundbreaking work of the late WSU and USDA-ARS wheat researcher Orville A. Vogel, who was acknowledged as a leader in the Green Revolution of the 1960s. “One reason Dr. Vogel’s semi-dwarf variety was so important was that it minimized lodging (plants tipping over in response to heavy wind or rain), which increased yields… Our work may increase yield per acre or yield per individual plant by manipulating levels of the plant’s natural growth hormone.”

What about wheat?

Like most wheat breeders, Kulvinder Gill, WSU’s O.A. Vogel Endowed Chair in Wheat Breeding and Genetics, is interested in increasing crop yields. But another one of his goals is to increase the yield of ethanol from wheat straw. The maximum proportion of straw that can now be converted into ethanol is half. “Fifty percent still goes to waste,” Gill said. “We think we can improve recovery by changing gene composition.”

It took Gill about four years to collect samples of the wheat lines from every major wheat breeding program in the world, some 800 in all, going back to varieties released in the 1950s. To test his hypothesis that lines vary in ethanol yield according to their straw composition, Gill is analyzing the lignin and cellulose content of each line so he can group them by high cellulose, low cellulose, high lignin, and low lignin content. From each of those classes, he will take representative samples and produce ethanol to identify any differences.

Gill says that once he identifies a wheat line with the right composition of cellulose and lignins, those genes can be transferred to the best Northwest varieties—a process that would take just two years.

Feeding biofuels production

More than 30 WSU and USDA scientists across Washington State also are evaluating a number of other crops that could feed biofuels production here and fit within the traditional rotation. The project, lead by Bill Pan, chair of the Department of Crop and Soil Sciences, and Chad Kruger, Center for Sustaining Agriculture and Natural Resources, focuses on crop adaptation and productivity in four major growing regions of Washington to improve their economic and environmental sustainability.

In eastern Washington, researchers are studying canola, mustard, and camelina oilseeds for their ability to germinate, establish, and flourish in dry soils, during harsh winters, and among diseases, insects, and weeds, as well as integrate into the wheat-barley-legume and wheat-fallow rotations of the region. Other candidates include sunflower, flax, linola, safflower, and lupine.

Irrigation water in the basins of central Washington reduces problems with oilseed crop establishment, but significant adoption is dependent on their economic competitiveness with local high-value crops. Scientists here are defining the management requirements and productivity of canola, camelina, sunflower, flax, safflower, and soybean oilseeds under irrigation. Growing peanuts is another possibility for this region.

In western Washington, organic canola production is under investigation for its potential demand from organic dairy producers and potential threat to the integrity of brassica seed production.

Columbia Basin scientists are testing switchgrass and giant reed for converting cellulose to ethanol. In addition, crop straw residues from perennial and annual wheats will potentially provide cellulosic biomass sources, but a harvest method is needed that won’t degrade soil quality.

Once the bottom-line farm economics of these alternatives are assessed, the research findings will be conveyed to growers, the biofuel industry, and government agencies. Field tours and WSU Extension materials are also forthcoming.

The beet goes on?

Sugar beet production in Washington State has a varied history. Currently, little occurs in the state, but given their high sugar content, researchers are expressing renewed interest in using sugar beets as a feedstock to support the ethanol industry in Washington State. Jonathan Yoder is leading a team of WSU ARC researchers to examine the potential of ethanol production from sugar beets in the state in terms of regional and agronomic adaptability, economic viability, and the opportunities and constraints of market development under current and potential market conditions.
Another feedstock possibility is poplar wood, which WSU researcher Jon Johnson, in collaboration with private industry partners, i s assessing for the production of ethanol. Johnson, based at the WSU Puyallup Research and Extension Center, is partnering with GreenWood Resources, a hybrid poplar company headquartered in Portland, Ore., and ZeaChem, a biorefinery technology company based in San Francisco, Calif., for plantings throughout the western U.S., Chile, and China. GreenWood has developed and patented a conversion process for ethanol production, while ZeaChem specializes in using such innovative processes to make renewable cellulosic ethanol economically viable.

Making poplars popular

The challenge Johnson and his collaborators face is in evaluating the quality of the feedstock from an ethanol producer’s perspective. “The problem with most studies is that they investigate either the production side or the conversion side of the process. What we’re doing is bringing those two aspects together,” Johnson said.

The following are some of the most encouraging economic, environmental, and agricultural advantages of poplars that Johnson has identified:

• Since poplars are a perennial tree, their feedstock can be “stored on the stump.”
• Poplars are cheap to grow, having low input costs, few tillage requirements, and little to no need for fertilization.
• Poplar productivity can be maximized for a particular region and climate through breeding.
• Poplars are the fastest growing temperate-region tree in the world and are widely adapted to grow in many soils and climates.
• Since poplars grow well on marginal land, they don’t take up valuable food-producing agricultural land.
• Poplars sequester carbon in soil, remove excess nutrients from soil and water, and provide food and shelter for animals.

Johnson figures that a 950-acre poplar farm could yield enough biomass to produce a million gallons of ethanol every year.

Processing and Conversion »