USC, Rice to develop bacteria-powered fuel cells

March 15, 2006

A diverse team of microbiologists, engineers and geochemists from the University of Southern California and Rice University are joining forces to create bacteria-powered fuel cells that could power spy drones that fit in the palm of a hand.

The Air Force has long been interested in micro-scale air vehicles - some as small as insects - but it has been stymied by the lack of a suitable, compact power source. With $4.4 million from the Department of Defense's Multidisciplinary University Research Initiative, or MURI, the USC and Rice research team hopes to prove its concept valid within five years by producing a self-propelled prototype.

At Rice, geochemist Andreas Lüttge will spearhead the team's efforts to understand how the bacteria Shewanella oneidensis attach to and interact with anode surfaces inside the fuel cell. Anodes are the parts of fuel cells and batteries that gather excess electrons for harvesting. To optimize its design, the team must understand how bacteria transfer electrons to anode surfaces under a variety of conditions.

"There are three primary components in the system: the bacteria, the surface and the solution that the bacteria are digesting," said Lüttge, associate professor of earth science and chemistry. "Any change in one variable will affect the other two, and what we want to do is find out how to tweak each one to optimize the performance of the whole system."

Lüttge's participation in the program grew out of a decade-long collaboration with principal investigator Kenneth Nealson, USC's Wrigley Chair in Environmental Studies and Professor of Earth Sciences and Biological Sciences. Nealson helped pioneer the field of modern geobiology and the investigation of the genetic pathways that some microbes rely upon to maintain their respiratory metabolism in oxygen-poor environments. Shewanella oneidensis, one such bacterium, uses metals instead of oxygen to fully metabolize its food.

"Since this organism is capable of passing electrons directly to solid metal oxides, it is not particularly surprising that it can do the same to the anode of the fuel cell, and since we are already in the business of understanding and optimizing the metal reduction capacity, it seemed a reasonable step to apply the same approaches to understanding current production. What is new here is the incorporation of colleagues in chemistry, geology, engineering, and evolutionary biology to optimize the entire system, not just the bacteria."

In the fuel cell study, Lüttge will use computer models to estimate how the bacteria will behave under different circumstances. Running tests on the computer will save time and money by allowing laboratory experiments to focus on best candidate approaches.

"One of the hallmarks of our approach is the vigorous feedback between our computer models and our laboratory work," said Lüttge. "The computer simulations help us perform better experiments, and the laboratory tests help us design better simulation, and the overall combination saves time and money."

In addition to the computational modeling, Lüttge will contribute his experimental skills in an imaging technique called Vertical Scanning Interferometry. The technique, which he helped create in the 1990s, combines information from multiple beams of light to resolve sample features as small as one-billionth of a meter. In previous studies with Nealson, Lüttge used the technique to examine how the cigar-shaped Shewanella attach themselves to crystalline surfaces. The researchers found that Shewanella would lay flat and orient themselves relative to minute defects in the crystal's surface.

"We still have a lot to learn about the chemical cues that the Shewanella use - both individually and in colonies - but they are incredibly efficient at converting organic inputs to electricity, so we are confident that they'll be a great candidate for our fuel cells," Lüttge said.
-end-


Rice University

Related Bacteria Articles from Brightsurf:

Siblings can also differ from one another in bacteria
A research team from the University of Tübingen and the German Center for Infection Research (DZIF) is investigating how pathogens influence the immune response of their host with genetic variation.

How bacteria fertilize soya
Soya and clover have their very own fertiliser factories in their roots, where bacteria manufacture ammonium, which is crucial for plant growth.

Bacteria might help other bacteria to tolerate antibiotics better
A new paper by the Dynamical Systems Biology lab at UPF shows that the response by bacteria to antibiotics may depend on other species of bacteria they live with, in such a way that some bacteria may make others more tolerant to antibiotics.

Two-faced bacteria
The gut microbiome, which is a collection of numerous beneficial bacteria species, is key to our overall well-being and good health.

Microcensus in bacteria
Bacillus subtilis can determine proportions of different groups within a mixed population.

Right beneath the skin we all have the same bacteria
In the dermis skin layer, the same bacteria are found across age and gender.

Bacteria must be 'stressed out' to divide
Bacterial cell division is controlled by both enzymatic activity and mechanical forces, which work together to control its timing and location, a new study from EPFL finds.

How bees live with bacteria
More than 90 percent of all bee species are not organized in colonies, but fight their way through life alone.

The bacteria building your baby
Australian researchers have laid to rest a longstanding controversy: is the womb sterile?

Hopping bacteria
Scientists have long known that key models of bacterial movement in real-world conditions are flawed.

Read More: Bacteria News and Bacteria Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.