OREGON STATE UNIVERSITY

OSU researchers strive to harness microbes to make hydrogen

10/06/2005

CORVALLIS, Ore. ­ Researchers in Oregon State University's Department of Bioengineering are spearheading efforts to develop sustained production of hydrogen fuel by harnessing photosynthetic microbes that use solar energy to split water molecules and make hydrogen.

OSU professors Roger Ely and Frank Chaplen were notified this week that they are receiving $900,000 over the next three years from a U.S. Department of Energy grant to bolster their efforts.

Hydrogen as a fuel source is a hot topic - hydrogen fuel is clean and energy-rich. Fossil fuels such as gasoline or coal generate greenhouse gasses, but burning hydrogen as fuel produces only water. To make hydrogen fuel takes energy, and current methods typically manufacture hydrogen from fossil fuels. To produce hydrogen fuel without emitting greenhouse gasses, a renewable form of energy would need to be used - from the sun, wind or from a biological process.

The technology to do this is not yet fully developed, but Ely and Chaplen hope to change this.

The two bioengineering researchers - who are faculty in both the College of Agricultural Sciences and the College of Engineering - are especially interested in the hydrogen-generating potential of a large group of photosynthetic microorganisms called cyanobacteria. These bacteria, formerly known as blue-green algae, naturally generate energy from sunlight and, under certain conditions, can make hydrogen rather than sugars.

Ely says cyanobacteria may be a perfect living source for a safe, efficient, and economical production of hydrogen for fuel.

"Imagine an ideal energy device," said Ely. "It wouldn't burn fossil fuels, and it wouldn't pollute. It would be made of low-cost, non-toxic materials, would run on the power of the sun, and would be safe, clean and economical.

"Nature has been conducting research and development on solar energy capture for about 3½ billion years and can teach us much," he said. "From looking to nature, we already know three key things: visible light constitutes most of the energy reaching the Earth; we know how organisms capture it; and we know how they convert it into chemical energy."

But the researchers must overcome a major hurdle: In natural systems, during photosynthesis, cyanobacteria stop making hydrogen when oxygen is present. "In the organism we are studying, oxygen interferes with the production of hydrogen by 'gumming up the works,' so to speak," explained Ely.

With the grant, Ely and Chaplen hope to develop, via "metabolic engineering," oxygen-tolerant strains of cyanobacteria that can produce hydrogen continuously in the light. After developing sun-harnessing, hydrogen-producing strains, the plan is to grow them by the millions in systems that could also store the generated hydrogen and, using fuel cells, convert it into electricity on demand. They call these proposed systems "solar biohydrogen energy systems."

"These systems can be designed to be relatively simple and economical, and could serve as decentralized sources of clean electrical energy," said Ely. "The process will have one input, sunlight, and two outputs, electricity and heat," he said. "It will be safe, will operate at relatively low temperatures, and could be made in a range of sizes - from home to industry scale - from abundant, inexpensive materials, mostly from carbon and silica."

"I want to make oil obsolete," said Ely. "As I like to say, the Stone Age didn't end because we ran out of rocks. We can do better."

Ely and Chaplen's efforts are in step with OSU's role as a Sun Grant University. As one of the country's five initial Sun Grant centers of excellence, OSU is a regional hub for evolving research, education and outreach programs largely focused on bioproducts and bioenergy.