ENVIRONMENT | Protecting our natural resources
24 June 2008
Botanic Energy Resources Make Hot Research Topics
National Arboretum showcases power plants to fuel the future
Washington -- Plants used or being considered for renewable energy sources are the featured celebrities at the U.S. National Arboretum, highlighted in a special exhibit during its Bioenergy Awareness Days launched June 21.
“Power Plants” features flora from around the world: field crops, palms, trees and flowering annuals. The 0.4-hectare (one-acre) exhibit aims to educate visitors about the raw materials of biomass.
“We have 21 plants on display here that are currently being used to produce ethanol and biodiesel or have the potential to do so. They range all the way from … traditional crops like corn and barley and soybeans and things that are tropical and subtropical, sugar cane and jatropha and cuphea, and even some unusual plants such as algae,” Arboretum Director Thomas S. Elias said.
Different regions of the world have different organic renewable energy resources, he said.
“This garden will give people a hands-on opportunity to see the plants,” Elias said.
“Is soy the answer? Is corn the answer? We are addressing a very relevant issue by having all the examples here so people can come and see and learn about them and help understand the issues.”
Garden director Scott Aker said of a unique patch of soybeans, “These are interesting because the trunks or stems of them can actually be used as cellulose for paperboard or for ethanol” and the soybeans for food. “These will get 6 feet [1.8 meters] tall, and they yield a lot of soybeans,” a “very good plant for no-till” farming, he said.
Under a big tent nearby, representatives from 27 American universities engaged in renewable energy research explained their projects.
WIDE RANGE OF PROMISING RESEARCH PROJECTS
Steve Taylor, director of the Auburn University Center for Bioenergy and Bioproducts, stood beside a portable biomass gasification unit engine, explaining the process as it chugged away. “We put woodchips in one end and electricity comes out the other end,” he said, holding up a jar of “very clean” synthetic diesel fuel made from biomass sources like wood or switchgrass.
The unit, the size of a large trailer, can be hauled easily to crop-residue accumulation sites.
“They are typically residues that you cannot afford to haul very far. Transportation is not cost effective. Onsite you can use it to generate your own power or other fuels,” instead of merely incinerating it, Taylor said. “It’s onsite power from onsite residue.” One goal is to reduce the cost of such power units.
Robb Walt, president of Community Power Corporation, a partner in Auburn’s research, added, “Theoretically you could absolutely provide power for a house” with household waste, but the current focus is to “provide farms with an opportunity to be energy independent.”
Among high-potential plants are algae. K.C. Das from the University of Georgia explained why algae are good candidates for energy generation. “It is a plant, even though it doesn’t have roots or leaves. It does the same thing, photosynthesis … and it’s the fastest-growing plant in the world.”
Its productivity outpaces other plants, and it has lipids -- “oils that may be extracted to make biodiesel, which is why it’s attractive,” Das said. It’s a nonfood oil, so demand for it would not affect food supplies.
Algae need a lot of water to propagate -- 1 ton needs 1 million gallons -- but they can grow in fresh or saline environments. Experiments growing algae in closed containers yield promising results, he said.
Algae’s lipid, carbohydrate and protein content make them potential sources for bioplastics, biofuels, food and feed. Several universities are pursuing algae research.
The University of Maine, located in America’s lushly forested northeast, turns forest waste into energy under its Forest Bioproducts Research Initiative (FBRI). The university recently received a $30 million grant from the U.S. Department of Energy (DOE) to build a small-scale commercial biorefinery.
FBRI Director Stephen Shaler said forest bioproducts include not only fuel and electricity, but chemicals and plastics. “Advances in science, coupled with better understanding of the ecosystem, the biology of tree growth and the chemistry of breaking down wood,” make refining more efficient, he said.
Innovative greenhouses that utilize all available space with multistory growing platforms and fuel pellets and nonpetroleum plastics from biomass and farm waste are other technologies in development.
Ernie Shea, from exhibit co-sponsor 25x25, said farmers are crucial in the sustainable energy effort, and will strengthen national security and rural economies. Doing it right, he said, means setting a clear goal and “producing energy in a sustainable way … that improves soil, water and air quality, in a way that doesn’t compromise food production. We feel that we can produce food, feed, fuel and fiber simultaneously to meet society’s needs, and do it in a way that is affordable.”
The National Arboretum, established in 1927, is administered by the U.S. Department of Agriculture’s Agricultural Research Service.
Learn more about nature’s power plants on the U.S. National Arboretum’s Web site.
See also “Advances in Technology Position Biofuels for Clean Future.”
