Fuel From the Sea
The sea has always been a source of food, travel and trade for humans. Now, researchers from NC State are trying to extract energy from the sea as well. A multidisciplinary team — from various departments in the College of Engineering and the College of Agriculture and Life Sciences — is genetically modifying marine algae to produce large amounts of fatty acids that can be processed into transportation fuels. The research team obtained $2 million from the Recovery Act through the National Science Foundation, which is funding graduate students and researchers to assist with the various steps needed to transform organisms from the sea into a tiger in the tank.
The process begins with Drs. Amy Grunden, associate professor of microbiology, and Heike Sederoff, associate professor of plant biology, inserting genes from microbes that live in extreme environments, such as deep-sea thermal vents, into a type of algae known as Dunaliella. Photosynthesis limits algae’s energy-production schedule to daylight hours, so the researchers are trying to force Dunaliella to mimic the ability of the extremophile microbes, which can produce food in the blackness of the deep sea. “We want that third shift operating, so the algae are producing lipids 24/7,” says Sederoff. The team chose Dunaliella because it can double its mass every 30 hours and because it lacks a cell wall, which makes it easier to process. Dr. JoAnn Burkholder, a professor of plant biology and algae expert, is studying several species of Dunaliella to see which performs best under various conditions, including changes to salinity and nutrient levels.
Meanwhile, Drs. Bill Roberts, Henry Lamb and Larry Stikeleather — professors of mechanical and aerospace engineering, chemical and biomolecular engineering, and biological and agricultural engineering, respectively — are working on the back end to refine the processing system that will turn the lipids into hydrocarbons, which can then be made into gasoline, jet or diesel fuel. The trio first developed the system a few years ago to process animal fats and vegetable oils into fuel. Roberts says they are using over-the-counter chemical compounds to simulate crops or products used as biofuels so they can optimize the hydrolysis process and the various catalysts used in the system. “There are a lot of knobs to tweak,” he says.
NC State also is adjusting its processing system to handle other species of algae and bacteria as feedstocks for their fuel-conversion process as part of two other Recovery Act-funded projects. “We need a higher-yield feedstock than what we have with crops and animal fats to meet our energy needs,” Roberts says. “We think algae could be the answer.”
About the Researchers:
- Burkholder Receives CALS/CNR Environmental Service Award
- Fill ’er Up – With Algae
- ASME Student Section