Tuesday, March 15, 2011

Another Biofuel -- Tequila

A plant commonly known for its role in the production of tequila has been overlooked as a source of biofuel that would not compete with food crops. Agave plants can sustain high yields while enduring extreme temperatures, droughts and carbon dioxide increases, with little need for irrigation, according to a series of papers in a special issue of Global Change Biology Bioenergy. With around 20 per cent of the world semi-arid, and some 200 agave species growing worldwide, utilizing this plant could help combat the potential energy crisis.

Field trials of the biofuel potential of some common Mexican varieties have begun in Australia and there are vast areas of abandoned agave plantations in Africa (once used for sisal fibre production, but abandoned after synthetic fibre production came along) that might be re-established for biofuel uses. This would avoid and economic impact food and would reduce the amount of additional land that would be cleared.

There are two different varieties: Agave mapisaga and Agave salmiana. When produced their energy yields far exceed corn, soybean, sorghum, and wheat productivities; and even without irrigation they still maintain high yields, according to another paper.

Arturo Velez, a former coordinator at the National Confederation of Forestry Producers and head of the Agave Project, an initiative to scale up agave biofuel production in Mexico claims that some varieties produce twice the dry biomass per hectare of hybrid poplar, three times the sugar of sugarcane, and four times more cellulose than eucalyptus, and capture five times more carbon dioxide than the most productive ecosystem. According to Velez, Mexico has 80 million hectares of arid and semiarid areas with no productive potential in which 5,600 million tons of dry biomass could be obtained from agave. This would be enough to meet the United States' transport fuel needs.

Different agave species are already widely used in Mexico for production of tequila and bacanora (traditional drink in Mexico) and henequen fibre (textile fiber made from a native Mexican plant), but in some cases up to 80 per cent of the plant's biomass is being thrown away.

Martín Esqueda, a researcher at the Feeding and Development Research Center in Mexico, warned that agave should be sustainably managed to avoid over-exploitation of the wild populations. This has happened with angustifolia species (lavender), which is now endangered because of unsustainable use to produce bacanora according to him.


  1. Interesting. I have not heard of this.. but it would be something to try -- especially with nearly 80% of the biomass being thrown out and because it can cover the fuel needs of the U.S. Why not put it to use?

  2. I agree that this is an interesting resource if biomass that would otherwise be thrown away is used, and if the growth does not involve extensive conversion of natural vegetation in arid areas into agave production. I am not sure how much of the 80,000 hectares mentioned includes land that is already under use, or whether the figure refers to all of the arid area that would be suitable. Deserts have a lot of interesting biodiversity, and it is important to preserve these ecosystems. Also, I imagine that making this work efficiently still requires development of the technology to convert cellulose into ethanol.