Wouldn’t it be great to get rid of animal (and maybe even human) waste in an eco-friendly way while also producing energy to run our cars? This scenario may be closer than we think. Researchers at North Carolina State University presented data at the annual conference of the Institute of Biological Engineering in Santa Carla, Calif last month that may bring us closer to this goal.
A tiny aquatic plant, called duckweed, was used to clean up animal waste stored in “lagoons” on hog farms. Growing this plant on wastewater produces five to six times more starch per acre than corn and captures nutrients that would otherwise pollute the environment. The fast-growing, high-starch duckweed can then be converted into ethanol, just as is currently being done with corn.
This is good news for those who have been arguing against the environmental friendliness of using corn as a bio-fuel. Concerns with using corn in this capacity include land competition for food crops, groundwater depletion, soil erosion, algae blooms, and the formation of “dead zones” in waterways inundated with pesticide and fertilizer runoff. The use of duckweed may convent some, if not all, of these problems. Indeed, duckweed may even reduce the nutrient (fertilizer) load on farms.
Dr. Jay Cheng, a professor of biological and agricultural engineering at North Carolina State University, and Dr. Anne-Marie Stomp, associate professor of forestry at North Carolina State University, are planning on continuing their research by establishing a pilot-scale project to help establish a large-scale system for growing duckweed on animal wastewater, and then harvesting and drying the duckweed for ethanol production. Let’s just hope they can keep the duckweed from contaminating natural bodies of water!