Enlarge Image Green crude. Harvesting oil produced by algae at Sapphire Energy's Green Crude Farm in Columbus, New Mexico. A new report says such existing technologies will need to use fewer external inputs to become sustainable. Credit: Sapphire Energy A report out today from the National Research Council (NRC) of the U.S. National Academies says that large-scale production of biofuels from algae is untenable with existing technology, as it would require the use of too much water, energy, and fertilizer. To improve matters, the report's authors suggest that the U.S. Department of Energy (DOE), which supports much of the...