As the world supply of fossil fuels dwindles, what alternatives to gasoline for vehicles are being developed?
Jimmy Bakeer, El Cajon ANSWER: These days, the buzzword is biofuels – fuels derived from organic matter. The two most common biofuels are bioethanol and biodiesel. Bioethanol is made from starchy crops in the same process that yields moonshine. Yeast ferments sugar into ethanol, which is distilled to remove water. Biodiesel is made from vegetable oils or animal fats. The U.S. has been ramping up production of ethanol from corn, but this cannot replace imported oil. Global corn prices have already increased as the grain is diverted from food chain to fuel tank. Corn is a difficult crop to grow. According to some pessimistic estimates, it requires nearly as much energy to cultivate corn and convert it to ethanol as is obtained from the ethanol in the end. However, there is a great deal of excitement about technologies to make ethanol from cellulose. Cellulose, the main structural component of plants, consists of long chains of sugars. An efficient process to convert cellulose into its co
