Hydrogen gas is thought to be the ideal fuel for a world in which air pollution has been alleviated, global warming has been arrested, and the environment has been protected in an economically sustainable manner. While algae have been mostly considered to be a feedstock for producing biodiesel (or in some cases ethanol), it is possible to produce hydrogen from algae.

For several decades, scientists have known that certain species of algae can produce hydrogen in anaerobic conditions. More recently, researchers have been trying to take advantage of this ability to produce hydrogen that could be used by fuel cells to generate electricity—without expensive processes like electrolysis required for splitting water into hydrogen and oxygen. More from here

A team of biologists from the University of Geneva and the Atomic Energy Commission, the National Center for Scientific Research, and the Mediterranean University, have demonstrated a new method for hydrogen production by algae. In a recent issue of PNAS, the team presented a method using copper to block oxygen generation in the cells of Chlamydomonas reinhardtii that could lead to a consistent cycle of hydrogen production. (source)

In order to induce hydrogen production in the algae, cells must be placed in an environment without oxygen but with access to light. To completely deplete the algae’s oxygen supply, in the experiment the researchers turned off part of a chloroplast gene required for oxygen evolution by adding copper to the cells in an enclosed chamber.Within about three hours, nearly all the oxygen was consumed by respiration, and the algae reached an anaerobic state. Without oxygen, the algae began to synthesize hydrogenase and then produce hydrogen.

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Mutant Algae is Hydrogen Factory

The mechanism of hydrogen photoproduction by several algae

Hydrogen Production. Green Algae as a Source of Energy: Hydrogen gas is thought to be the ideal fuel for a world in which air pollution has been alleviated, global warming has been arrested, and the environment has been protected in an economically sustainable manner. Hydrogen and electricity could team to provide attractive options in transportation and power generation.

Algae Could One Day Be Major Hydrogen Fuel Source: As gas prices continue to soar to record highs, motorists are crying out for an alternative that wont cramp their pocketbooks.

Hydrogen Production. Green Algae as a Source of Energy