Jul 30, 2007 — As the U.S. looks for ways cut dependence on foreign oil and reduce greenhouse gas emissions, biofuels are rising toward the top of the mix of alternative fuels. Bio-fuels such as ethanol or bio-diesel burn cleaner than oil-based diesel and are seen as an environmentally-friendly replacement for our 60 billion gallon per year thirst for diesel oil. They're made from plants, and here's the rub. There aren't enough crops or land to produce enough bio-diesel to replace fossil fuel-based diesel. New research is looking at another raw material: algae. Amy Quinton reports.