Agave shows potential as biofuel feedstock

By Anna Austin
Mounting interest in agave as a biofuel feedstock could jump-start the Mexican industry, according to agave expert Arturo Valez Jimenez.

Agave thrives in Mexico and is traditionally used to produce liquors such as tequila. It has a rosette of thick fleshy leaves, each of which usually end in a sharp point with a spiny margin. Commonly mistaken for cacti, the agave plant is actually closely related to the lily and amaryllis families. The plants use water and soil more efficiently than any other plant or tree in the world, Jimenez said. "This is a scientific fact-they don't require watering or fertilizing and they can absorb carbon dioxide during the night," he said. The plants annually produce up to 500 metric tons (551 tons) of biomass per hectare (2.47 acres), he added.

Jimenez developed The Agave Project, which began four years ago when he was the national administrative coordinator at the National Confederation of Forestry Producers in Mexico, with a goal to explore and promote the potential of the plant. He is now developing the project separately from the agency, and said the project extends into all 17 agave regions of Jalisco State (Central-Western Mexico) and will soon become nationwide. Jose Luis Ortega, a local congressman, Juan Frias of Bioenergy Solutions, Juan Villalvazo, a professor at the University of Guadalajara, the Mexican Agavaceas Net and the State Council of Agave Tequilana Producers are also participating in the project, he added.

Agave fibers contain 65 percent to 78 percent cellulose, according to Jimenez. "With new technology, it is possible to break down more than 90 percent of the cellulose and hemicellulose structures, which will increase ethanol and other liquid biofuels from lignocellulosic biomass drastically," he said. "Mascoma (Corp.) is assessing such technology."

Mascoma research scientist Heidi Hau told Biomass Magazine that the company is currently evaluating agave as a potential feedstock, and has conducted some preliminary tests in-house that warrant further testing. "Although we are very much in the evaluation stage, we have not yet committed to a project," she said. Jimenez said the Mexican Ministries of Economy and Agriculture are interested in having Mascoma visit Mexico for that purpose and are providing their assistance.

Beyond Mascoma, the Energy Biosciences Institute at the University of Illinois is planning a small invitation-only agave workshop in Mexico. Researcher Sarah Davis said the institute may plan a larger meeting at a later date, depending on the outcome. Jimenez said he believes the workshop will be a leap forward in the research of agave for biofuel production.

Jimenez is also working with Washington-based Clearsky Energy Systems Inc., which is exploring the possibility of building municipal electricity-generating facilities that run on syngas produced from the gasification of agave biomass. "They are also assessing a new technology for sustainable electricity generation that is cheaper than syngas, produces more energy and is cleaner," he said.

Annually, Mexican agave could produce more than 5 billion metric tons of biomass, using only marginal land," Jimenez said. "We have discussed producing huge quantities of biocrude and syngas in Mexico and to export it via PEMEX (Petroleum Mexico) to the U.S." A biofuels director at a renewable energy laboratory in the U.S. indicated that agave biocrude could sell for the same price as oil, Jimenez said. "The Mexican government is very interested in biofuels production," he added. "Mexican oil production at Cantarel fell 50 percent in just five years and production is decreasing at an alarming rate of 14 percent annually."