Biofuels and weed

Plants that can be grown for fuel are often touted as a vast, clean energy source-except by those who say precious food is being diverted into gas tanks, and that biofuel crops are using up dwindling land and water. Enter willow, hemp and switchgrass. Scientists say research into a new generation of biofuel sources could yield cheap energy supplies that do not compete with food crops-or with nature-for water or space. Goran Berndes, a researcher at Chalmers University of Technology in Sweden, says the list of possible plants goes far beyond the established crops-such as corn, maize and sugar cane-that are already grown commercially for fuel uses. "Bioenergy is much broader," he said. "Most people working in bioenergy expect other crops to dominate in the long term."

One promising energy source is the willow, a northern plant used to make baskets and sport bats. Others include hemp, known for its rope- making and mind-altering qualities, and switchgrass-a reedy plant found in the US Midwest. A new crop that is being already used is Jatropha, a resilient, oil-rich, tropical plant that can be grown on waste land and even introduces nutrients to the soil. Its oil is already used in India to power diesel cars and turbines. Jatropha has grabbed headlines because it avoids the biggest controversy surrounding biofuels: the ethical debate over whether agricultural resources should be used for energy when millions across the planet go hungry. Also, biofuel crops themselves can carry severe risks for the environment, especially if hitherto unfarmed land is converted to agricul ture with large amounts of fertilizers and irrigation.

The International Water Management Institute, which led a five-year global study on water involving more than 700 researchers, found that if China and India pursued their current biofuel plans, they faced water scarcity by 2030. At least one business sector is prepared to lobby for biofuel crops that do not compete so hard with food production. Nestlé, the world's largest food company, says the subsidies being applied to current biofuel crops are distorting the market and pushing up the prices of food crops, and that second- generation biofuels could be an answer. "If it works, and if it can be made to work economically, that certainly would be-both from an environmental and from an economic point of view-a much better solution than this strong focus on the current first-generation food crop biofuels," said Claus Conzelmann, Nestlé vice-president for safety, health and the environment.