Many advanced biofuels processes require additional hydrogen in order to complete the fuel synthesis. Origin Oil has developed a means of converting light energy to hydrogen using algae in its "multireactor" and "Hydrogen Harvester" technology. Photosynthetic organisms split water into oxygen and hydrogen in the course of producing carbohydrate. (carbon dioxide is also split to provide the carbon in carbohydrate) Depriving algae of Sulfur can divert them from producing carbohydrates and lipids to the greater production of hydrogen.
OriginOil researchers built a pared-down version of the company’s Hydrogen Harvester™ and tested many process variables and materials. They achieved hydrogen energy corresponding to a solar energy conversion efficiency of about 12 percent continuously for several hours on a partially clouded day. The sole energy input was the Sun. By comparison, commercial solar cells achieve conversion efficiencies between six and 20 percent.
Brian Goodall, OriginOil’s CTO, said: “Our experiments clearly demonstrate that this technology can generate renewable hydrogen at rates that matter to the global economy. These early rates compare well with those of the more mature solar cell industry, with the added benefit that the fuel, hydrogen, is readily storable. This is the first renewable source for today’s $39 billion hydrogen market.”
OriginOil officials admit the in-the-field efficiency might be less than the 12 percent achieved in the research system. However, since algae stores up energy during the day, it will continue to generate hydrogen throughout the night. Also, algae production facilities using a Hydrogen Harvester could be self-sufficient for refining. _DomesticFuel
This process can be very useful for a complete advanced biofuels plant. Some algal reactors can be dedicated toward producing lipids or pyrolysis / synthesis gas. Other algal reactors can be dedicated toward hydrogen production. The hydrogen can then be utilised to convert lipids to hydrocarbons, or to synthesise hydrocarbons from pyrolysis products or synthesis gas via catalytic processes.