Travellers in rural Australia are familiar with Agave americana. The blue-green leaves of the century plant are often the only reminders of long-abandoned farmhouses.
Agave was introduced into Australia for ornamental and possibly medicinal purposes, and has proved to be a successful survivor in the often arid Australian landscape. Now, researchers are asking if that capability could be the basis of a sustainable biofuel industry.
The agave plant has not yet been widely cultivated as a fuel source, but it promises some significant advantages over existing sources of ethanol such as sugarcane and corn. It can grow in arid areas without irrigation, and it doesn't compete with food crops or put demands on limited water supplies.
Food or Fuel?
Due to its rich reserves of coal, natural gas and uranium, Australia is nominally self-sufficient in energy, except for transport fuels and heavy oils. At the moment, bioethanol and biodiesel are being imported as renewable replacements for petrol and diesel, respectively.
Attempts to reduce our dependence on petrol have established sugarcane and corn as popular sources of biofuel, but not without considerable cost. Not only do they compete with food crops for arable land, they can affect water quality through excessive fertiliser use and lead to undesirable land-use changes such as...