Hydrogen has the potential to be a clean and sustainable fuel, but realizing that potential relies of clean and sustainable methods to produce it. Algae might fit the bill, but it only produces hydrogen in small amounts. Now, using genetic engineering, researchers at Tel Aviv University (TAU) have modified the organism, which could enable it to be used to mass-produce hydrogen on an industrial scale.

Hydrogen might burn clean, producing only water as a by-product, but currently over 90 percent of the hydrogen produced in the United States comes from fossil fuels. Although algae can produce hydrogen using photosynthesis, it was believed that this only occurred for a few minutes at dawn, resulting in limited amounts of the gas. But tests by a team led by Dr. Iftach Yacoby, the head of TAU's renewable energy laboratory, have revealed that algae actually produces hydrogen throughout the day.

Further tests revealed that the enzyme hydrogenase, which breaks down in the presence of oxygen, was integral to algae's hydrogen production. Through genetic modification the team was able to remove the oxygen so the hydrogenase is able to keep producing hydrogen, resulting in a boost in hydrogen production of 400 percent.

"The discovery of the mechanisms makes it clear that algae have a huge underutilized potential for the production of hydrogen fuel," says Dr. Yacoby. "The next question is how to beef up production for industrial purposes – to get the algae to overproduce the enzyme."

Dr. Yacoby is now hunting synthetic enzymes that can do just that. If he and his team prove successful, algae could soon be pumping out mass quantities of the clean-burning fuel.

"I grew up on a farm, dreaming of hydrogen," continues Dr. Yacoby. "Since the beginning of time, we have been using agriculture to make our own food. But when it comes to energy, we are still hunter-gatherers. Cultivating energy from agriculture is really the next revolution. There may be other ways to produce hydrogen, but this is the greenest and the only agricultural one."

The team's research appears in back-to-back studies published in Plant Physiology and Biotechnology for Biofuels.