Firing Up Bio-Energy
Skyrocketing gasoline and diesel prices at the pump are fueling interest in alternative energy
resources throughout the United States. But more than cost is driving research in alternative energy at Oregon State University. OSU scientists are looking for cleaner fuels that are easier on the environment and new ways to convert agricultural crop materials into useful fuels.
Alternative energy is a lot of things, including solar, wind, and hydro power. Bio-energy generated from plant material is also an alternative, all part of our nation’s strategy to reduce dependence on energy imports, most notably foreign oil imports from South America and the Middle East. In the Pacific Northwest, the upwelling interest in bio-energy helped bring $8 million in research funding to Oregon State University through the federal Sun Grant Initiative, passed into law in 2003.
Interest in agricultural crops as a possible source of liquid fuel goes back to the 1940s with early work on ethanol, an alcohol-based fuel distilled from plant
material. However, after World War II the price of gasoline dropped to pennies per gallon and work on ethanol was shelved. Gas remained cheap until the Arab oil embargo in the early 1970s, when the Organization of Petroleum Exporting Countries (OPEC) stopped shipping oil to several western nations. Almost overnight, U.S. gasoline prices quadrupled, a stark reminder of how dependent the U.S. had become on foreign oil imports.
The Arab oil embargo was shortlived, ending in 1974. However, U.S. dependence on foreign oil imports continued to grow. One result of this thirst for foreign oil has been renewed interest in bio-based energy alternatives.
Work by Mike Penner, a food chemist at OSU’s College of Agricultural Sciences, is a good example of innovative research that may have applications for alternative energy. Penner is studying leftover grass seed straw and fruit pulp to find compounds that may be used to make other products, such as ethanol. There is a tremendous amount of straw left in the Willamette Valley after grass seed harvest each year. In addition, fruit processors in Oregon are interested in finding uses for the pulp left over from product processing. As it stands now, many growers and vintners have to pay to have such waste material hauled away for disposal.
“We look at how plant cell walls resist decomposition and we work towards developing biologically based systems that can rapidly break down plant materials in environmentally friendly ways,” Penner explained, “with the goal of obtaining industrially useful compounds such as sugars.”
Penner is not focusing so much on final products, but rather on getting at the intermediate compounds in plant materials, such as the different sugars that may be available in grass seed straws. Other researchers are looking at processing those compounds into end products, such as fermenting sugars from straw to produce ethanol.
“We’re certainly interested in energy as one of the products, but there will likely be other high-value products, including biochemicals and specialty solvents,” Penner said. For any process, he added, it is very important that the energy and costs involved in obtaining the compounds don’t exceed the benefit of the results.
Penner, with plant physiologist Gary Banowetz of the USDA Agricultural Research Service, is developing technology to use grass seed straw as fuel to generate energy. Banowetz is working with energy laboratory scientists at the Western Research Institute in Wyoming to build a prototype gasification reactor that burns grass seed straw to produce synthetic gas, or syngas, which consists mostly of carbon monoxide and hydrogen.
“This reactor will be designed for on-farm generation of electricity and should cost approximately the same amount as a new combine—about $350,000,” said Banowetz.
That amounts to a lot of gas, about 140,000 gallons at $2.50 per gallon. The gasification technology will successfully convert grass seed straw to energy products. But, can this technology be made economical and user-friendly so farmers don’t need the help of engineers to operate it on the farm? Banowetz plans to address those questions next year when his team will build and test a prototype gasification reactor in the Willamette Valley.
In OSU’s Department of Biological and Ecological Engineering, Roger Ely takes a different angle on bio-based energy generation. Ely, an environmental engineer, and Frank Chaplen, a bioprocess engineer, are harnessing cyanobacteria to use solar energy to produce hydrogen.
Hydrogen is touted as an alternative fuel for automobiles and as a key component in fuel cells that generate electricity. Using hydrogen as a fuel is clean: water is its only by-product. But current methods of producing hydrogen require energy, including fossil fuels. This tends to cancel out the benefits of hydrogen fuel applications. So the scientists are looking to microbes as a source of hydrogen.
“Cyanobacteria, also known as blue-green algae, use solar energy to split water into oxygen and hydrogen, but they do it under limited conditions and for very brief periods of time,” said Ely. “Our goal is to extend the time and conditions under which these bacteria produce hydrogen.” The major challenge that Ely must overcome is that cyanobacteria only produce hydrogen in the absence of oxygen. Success is dependent upon finding oxygen-tolerant strains of cyanobacteria. Recently Ely and his colleagues received a $900,000 grant to develop methods to evaluate different conditions and strains of cyanobacteria for their ability to make hydrogen.
Just down the hall from Ely in the Department of Biological and Ecological Engineering, another researcher is using microorganisms in yet another way. Hong Liu is working on development of a microbial fuel cell that can use sewage or wastewater from animal and crop production to generate electricity, simultaneously cleaning the water. This technology uses bacteria present in wastewater to break down organic material into basic components, including carbon dioxide, hydrogen ions, and electrons. The electrons flow through a circuit to produce electrical energy and combine with hydrogen ions and oxygen to form clean water.
Liu is also working on a variation of the microbial fuel cell that uses the BEAMR (bio-electrochemically assisted microbial reactor) process to generate hydrogen. In this approach, oxygen is removed from the cell and small amounts of electricity are introduced into the system. Instead of combining with oxygen and electrons to form water, hydrogen ions released from wastewater are captured as hydrogen gas.
“Basically, these technologies can harvest electricity or hydrogen from any biodegradable material, even wastewater,” said Liu. “This is really promising, but there is a lot of work we need to do.”
Another promising bio-energy technology is biodiesel, which is produced through a chemical reaction in which vegetable oil is combined with alcohol. This process yields methyl esters, which is the chemical name for biodiesel, and glycerin, a by-product used in soaps and plastics. Researchers have produced biodiesel from many sources including leftover cooking oil. Although usually odorless, biodiesel may take on the aroma of, say, french fries or doughnuts, giving a fragrant clue to the oil’s original use.
Biodiesel has recently become the rallying cry of a group of OSU students interested in developing alternative fuels who have banded together to form the OSU Biodiesel Initiative.
“The premise of the initiative is to make Oregon more energy self-
sufficient,” said David Hackleman, a professor in OSU’s Chemical Engineering Department and faculty advisor for the initiative. Students, faculty, and people in the community work together on biodiesel research projects. Many use a small biodiesel production reactor located in Gleeson Hall on the OSU campus.
“We are looking for easier and more efficient ways to make biodiesel,” said Hackleman. “Another goal is to develop small-scale biodiesel production platforms that can be efficiently operated by individual farmers, state and community government organizations, and commercial vehicle fuel outlets.”
The OSU biodiesel group has worked with OSU Parking Services to introduce biodiesel as fuel for campus shuttle buses, and the group is working with the OSU Motor Pool on a small-scale biodiesel production facility to provide fuel for their diesel trucks. Currently, biodiesel production in the Pacific Northwest is tiny compared to the large-scale processing capacity in the Midwest. But as large biodiesel processing facilities sprout up in the region, agricultural producers here will be needed to deliver energy crops to keep the biodiesel flowing.
OSU researchers including Tom Chastain, crop scientist in Corvallis, and Don Wysocki, OSU Extension soil scientist at the OSU Columbia Basin Agricultural Research Center near Pendleton, are evaluating canola, an oilseed crop, for Oregon production. Currently, most U.S. canola production is centered in North Dakota and Minnesota. Wysocki is working with Jack Brown, University of Idaho crops researcher, to study the adaptability of canola to eastern Oregon climates and to identify the best planting and harvest methods for the crop.
“The crop grows well in Oregon,” Wysocki said. “However, Oregon growers are not enthusiastic about producing it because the current market price for canola in Oregon is about 8 cents per pound. Growers here need a price of about 12 to 14 cents per pound for canola to return a profit.”
The extra pennies per pound are crucial, Wysocki explained, because there are no large-scale canola processing facilities in the Pacific Northwest. This means growers must ship canola to processing facilities in other regions, which adds freight costs.
This illustrates a drawback with the production of biofuels that must be considered, according to Russ Karow, head of the OSU Crop and Soil Science Department.
“Economics are a key, and the economics of some of this just doesn’t work as far as production is concerned,” he said. Karow noted that while we can produce biofuels, this may lead to false benefits in some cases because fossil fuels are used to produce the biofuels. Producing energy crops requires tractors, tractor fuel, and fertilizers, which come from fossil fuels.
“It’s important to be aware of the ratio of energy output per unit of energy input for some of these different fuels,” said Karow. “Some people say there is a net energy gain in production of biofuels. Others dispute that. If all factors are considered, such as biofuel production subsidies and federal subsidies for the production of many crops in addition to actual costs of production, in my opinion there is not a net gain in the production of biobased energy at this time,” Karow said.
“However, producing biofuels locally does give us greater control than importing energy,” Karow added. “And if the energy input versus energy output is reduced below the level for fossil fuels, then we buy ourselves time to find other solutions to our fossil-
Finding bio-energy alternatives that offer potential — economic and otherwise — will get a boost from the Sun Grant Initiative and OSU’s designation as the western Sun Grant research center of excellence.
“We’re funded at over $2 million a year for four years,” said Thayne Dutson, dean of the OSU College of Agricultural Sciences. “Our role in the initiative provides an opportunity to broaden bio-energy research at OSU, and it fits perfectly with one of the college’s strategic goals.”
Jan Auyong, assistant director of Oregon’s Agricultural Experiment Station, directs OSU’s participation in the Sun Grant Initiative. And, as the western center of excellence, OSU will oversee the Sun Grant Initiative across a region that stretches from Alaska south through California and from Utah west to the Pacific islands.
“This initiative not only provides for research but also for outreach to extend new technology to people and communities that can use it,” Auyong said. “The initiative will foster increased collaboration between institutions, federal research efforts, state agencies, and communities.”
“The world’s petroleum energy system is fragile,” Dutson added. “The sooner we develop some ways to reduce our dependence on petroleum for fuel, the better off we will be. The research investment made possible through the Sun Grant Initiative funding will allow us to enhance many of the things we’ve already started at OSU and explore the potential of new technologies as well.”