Hugh Pickens writes "Algae has long been known as a promising source of biodiesel. It's worth noting, though, that algae also produces a small amount of hydrogen during photosynthesis. The MIT Technology Review reports that researchers have created a mutant algae that makes better use of sunlight to increase the amount of hydrogen that the algae produce. Anastasios Melis and his team at the University of California have manipulated the genes that control the amount of chlorophyll in the algae's chloroplasts. Although the process is still at least five years from being used for hydrogen generation, Melis estimates that if 50% of the algae's photosynthesis could be directed toward hydrogen production, an acre could produce 40 kilograms of hydrogen per day. At the price of $2.80 a kilogram, hydrogen could compete with gasoline, since a kilogram of hydrogen is equivalent in energy to a gallon of gasoline."