Someone mentioned to me today that studies say that producing ethanol or biodiesel uses up six times more fossil fuel energy units to produce one, thus defeating the purpose. I looked it up and found this article about a 2005 Cornell University and University of California Berkeley study that concluded the same thing. Critics say that the study was based on old farming and ethanol production technologies. A 2006 study refuted the earlier findings, stating that corn grain ethanol and soybean biodiesel do produce more energy than is needed to grow the crops and convert them into biofuels. However, they all agree that biodiesel is not enough to meet U. S. energy demands. I saw a show on the Travel Channel featuring Brazil, one country that has reduced its dependence on gasoline by producing ethanol fuel from sugarcane. Brazilian cars can run on alcohol or gasohol, and the cheaper alternative at the pump is often the ethanol. U. S. ethanol production is based on corn, a more expensive and lengthier process. The debate here in the U. S. will continue.