The rush is on for biofuels to end dependence on oil, help solve global warming and create jobs for the rural poor. In America's corn-belt, especially in Iowa, there's a rush to produce ethanol. States and the federal government are providing incentives, including subsidies, for fuels derived from agricultural products. But a new UN report says the benefits of biofuels-including ethanol-may be offset by environmental damage, and there is growing concern about their impact on the price of food. We examine the pros and cons of energy from agricultural products. Is it really cleaner and cheaper? Is the US moving too fast?