And the next plant-based fuel is ... duckweed

Growing duckweed on hog farms could not only clean up animal waste but provide a biofuel energy stock with five to six times more starch per acre than corn, according to researchers at North Carolina State University.

That means duckweed could become an ethanol source that’s “faster and cheaper than from corn,” said researcher Anne-Marie Stomp.

“We can kill two birds — biofuel production and wastewater treatment — with one stone: duckweed,” said researcher Jay Cheng. What’s more, he added, duckweed starch could easily be processed in facilities that currently produce corn-based ethanol.

Unlike corn, duckweed doesn’t raise the spectre of trading food for fuel, as corn does. Growing the plant for fuel could at the same time address the serious problem of livestock-based wastewater pollution.

Industrial-scale hog farms currently store animal waste in large open-air “lagoons” that contribute to air pollution. Duckweed can use the nutrients in that waste to reduce that pollution and clean the water.

“There’s a bias in agriculture that all the crops that could be discovered have been discovered,” said Stomp. “But duckweed could be the first of the new, 21st century crops. In the spirit of George Washington Carver, who turned peanuts into a major crop, Jay and I are on a mission to turn duckweed into a new industrial crop, providing an innovative approach to alternative fuel production.”

The two researchers are currently creating a pilot-scale project to determine the best way to build large-scale systems for growing duckweed on animal wastewater, then harvesting and drying the duckweed.