Photograph by Josh Monken
All around us, organisms react to each other and their environments—they always have. And while they’re at it, they produce energy. We haven’t paid these processes much attention until recently, because we’ve had affordable gas. But now that’s changing, and as it does, the government and the scientific world are looking for alternative energy sources.
That’s where three St. Louis researchers come in. Like the organisms, they’ve been busy—not with ethanol, windmills or solar power, but with those microscopic processes already surrounding us.
Among the many researchers seeking alternatives—and there are many—are the University of Missouri–St. Louis’ Teresa Thiel, Washington University’s Muthanna Al-Dahhan and Saint Louis University’s Shelley Minteer. All of them are working on potential solutions that don’t get a lot of press. All of them have achieved some level of success. And all of them are taking science that’s always existed and finding ways to make it better fit our needs.
For each of these researchers, life in science is full of frustrations. Creativity is often stifled by limited resources and funding. “We have to sell our science,” says Thiel. “And it’s expensive.” Research is competitive and often dulled by academic obligation. Yet it’s also exciting. It offers something most of us won’t find at a desk—a peek into the future, which to some might look like a sci-fi fantasy, but to others looks like a way out of our energy mess.
The Pond Scum Solution
The students struggle to find the right words. They don’t want to fall into lab-speak about nitrogen fixation and gene regulation in filamentous cyanobacteria—or blue-green algae, to the layperson. It’s a challenge they often face once outside the fourth-floor lab on the UM–St. Louis campus. “My friends wonder what I work with, and I tell them it’s pond scum,” says doctoral student Justin Ungerer.
“Then you try to explain how cool pond scum is …” says Han Lim, a fellow graduate student.
First impressions aside, cyanobacteria’s potential is staggering. So staggering, in fact, that Teresa Thiel, professor of biology and dean of the university’s College of Arts and Sciences, has worked with these bacteria for 27 years while trying to harness their potential. She works with a process called nitrogen fixation, in which the bacteria convert nitrogen into ammonia, creating hydrogen as a byproduct. Thiel and her students hope to manipulate cyanobacteria’s genes—reprogram them, let’s say—to make more hydrogen and to sustain its production. “The roadblock in many ways is the organisms themselves,” Thiel says.
But if successful, cyanobacteria’s benefits could far outweigh other possible energy solutions. Unlike corn-based ethanol, for example, nitrogen fixation doesn’t produce carbon emissions or affect food prices. “It’s completely renewable because it’s sunlight,” says Thiel, who also points out that there’s no pollution because the only byproduct is oxygen. And unlike ethanol, which is mixed with gasoline, the hydrogen needs no mixing. It doesn’t require fertile soil or lots of space either—in fact, the bacteria don’t need land at all. Some suggest storing cyanobacteria in the ocean, while Thiel pictures storing them in the desert.
It sounds ideal. But currently only a handful of labs in the nation are working on it. “I’m astonished that it hasn’t caught on as a more direct approach than others are taking,” says C. Peter Wolk, a researcher at Michigan State University’s Department of Energy Plant Research Laboratory and Thiel’s postdoctoratal adviser. Researchers could produce 40 times more hydrogen with cyanobacteria within the next five years. “It could take longer,” Wolk says. “It’s really hard to say. It’s partially a question of funding.”
Even then, we won’t be shopping for hydrogen-powered cars anytime soon. Such cars exist as prototypes in California and Florida, but there are only about 25 hydrogen refueling stations nationwide. “It’s definitely not going to happen in the near future,” says Ungerer. “But when it does happen, I see it as the perfect alternative fuel source.”
The Manure Solution
Most evenings in Iraq, as the sun set near the Euphrates River, tall streetlights began to glow. Years ago, a boy sat beneath one of the lights and studied. He was top in his class, had been every year and would be in the future. As long as he applied himself, Muthanna Al-Dahhan believed he would succeed. He was right then, and he might be right now—though he never guessed the focus of his academic endeavors.
Al-Dahhan came to Washington University in 1988 to earn his Ph.D. After a stint in the private sector, he returned to teach at Wash. U. All along, the man from the oil-rich country was eyeing biofuel production, and his interests found financial backing to the tune of $2.1 million when the Department of Energy solicited alternative energy proposals in 2000. “That time, the price of oil went up,” recalls the professor for Washington University’s Department of Energy, Environmental and Chemical Engineering.
With government funds, Al-Dahhan studied anaerobic digestion, a process by which anaerobic bacteria digest waste and create biogas. Using the process inside a digester, an oxygen-free system that holds the waste, he hoped farmers could turn manure into energy and, at the same time, remove methane from the air. Already, there are about 100 anaerobic digesters being used on commercial farms in the United States, according to information released by the Environmental Protection Agency’s AgSTAR Program. However, a high percentage of these digesters regularly fail. Not that they don’t run, but they don’t produce enough energy to cover the cost of running them, says Brian Davison, chief scientist for systems biology at Oak Ridge National Laboratory in Iowa.
Enter Al-Dahhan. He found a lack of uniformity in anaerobic digestion research. Scientists had only studied small digesters, but no lab had tested the many variables that go into the process of anaerobic digestion. For five years Al-Dahhan, his colleagues and researchers at Oak Ridge National Laboratory studied every aspect of anaerobic digestion.
But how could they see what was going on inside a heap of manure? “You can’t really look inside,” says Lars Angenent, a Cornell professor who collaborated with Al-Dahhan on the project. Using technology created for the medical world, Al-Dahhan and his team used a multiparticle radioactive tracking system—a device similar to X-rays—to understand what was happening inside the digesters. What they found was that none of the variables made much of a difference on a small scale. But on a larger scale, dead zones developed and left pockets where digestion didn’t take place. They also discovered that the components that went into the mix and the speed at which digestion occurred very much mattered.
Still, there’s much work ahead. Dead zones continue to exist, as do other variables that go into the process. Al-Dahhan hopes to further study those variables, which he says can’t be done without using his technology—and money, which he’s out of. But despite the remaining obstacles, Al-Dahhan hopes to simplify the process as much as possible. He pictures a day when farmers can go to supply stores and pick up lightweight plastic digesters that they can easily operate. “Identifying the problem is essential for solving it,” Davison says. “But it doesn’t by itself solve it.”
The Bio Battery Solution
Shelley Minteer, a 33-year-old Illinois native, came to Saint Louis University’s Department of Chemistry in 2000. Within three years she had patented a way to prolong the life of a bio battery—one that runs on renewable energy sources instead of corrosive heavy metals. “As a researcher she’s been able to come up with pretty significant breakthroughs,” says Nick Akers, one of Minteer’s former students. With a background in electrochemistry, Minteer worked to find ways to power fuel cells using hydrogen and oxygen—a dangerous mix. “I didn’t want to be responsible for biweekly explosions,” Minteer says. Instead, she wanted to create a bio battery that converted energy while remaining safe and renewable—and she needed the battery to last.
Other researchers were already using enzymes as a chemical catalyst to produce energy in bio batteries. The problem was that the energy quickly escaped, due to the materials’ sensitivities to light and temperature, which only allowed the batteries to last a few days. Before starting at SLU, Minteer had worked with polymers that contained tiny pockets and pores. She decided to try something that had never been done before: using the polymers to entrap enzymes. “It’s not something a normal person would think about,” says Akers. Initially, Minteer figured there was a 5 percent chance the polymers would actually work. She was way off. By spring 2002 one of Minteer’s students, Christine Moore, had successfully encapsulated simple sugars inside fuel cells thanks to the polymer, which functioned like a kind of straitjacket to restrain the energy and make the battery last.
Akers, a SLU grad student at the time, got involved. “He’s a real practical guy,” Minteer says, “so he took things to more of a useful configuration to make something that was reproducible and usable.” By that November the team had successfully created a bio battery that ran on alcohol and lasted between 45 and 60 days. Minteer and Akers patented their polymer process in 2003 and the next year founded a company, Akermin, to build on that work.
For the next several years, national and local media alike usually got at least part of the story wrong, spinning the breakthrough as a bartender’s dream. “An enzyme-catalyzed battery has been created that could one day run cellphones and laptop computers on shots of vodka,” New Scientist reported in March 2003. “Charging your cellphone battery with vodka from a cocktail is a possibility Shelley Minteer wants to make a reality,” the St. Louis Business Journal reported in early 2006.
Sounds sexy, but it’s not quite true. “That’s not where any of this stuff is going,” Akers says. While it would be nice to have a cellphone battery last a year, pouring shots into the phone would be messy, Minteer points out, and probably not the best use of the technology. Instead, the company is working with the Department of Defense to create wireless security systems, as well as small and lightweight power sources the military could use in remote locations.
Akermin’s process is nearing commercialization, according to Minteer, with the bio battery maintaining a life of one to two years. Currently, though, she spends most of her time teaching and overseeing her students in the lab at SLU, where the students are developing ways to create fuels out of waste, including glycerol (a waste product of biodiesel production) and glycol (the main ingredient in antifreeze). “She sleeps three hours a night,” Akers says. For now, Minteer seems able to make that energy last, too.
The Reality
So what do all of these options mean for our energy needs? In the near term, nothing. “I don’t think the solution to our energy problem is right around the corner,” Thiel says, adding that the solution might not come in one neat package, either. “It’s not going to be like it is with fossil fuels. That day will end.” Minteer agrees. “Really, I’m not sure that there is one perfect biofuel,” she says. Energy sources might vary based on the location. “Wind in some areas may make sense,” Thiel says. “Waves in some areas may make sense.”
While Minteer and others hope the next energy source is environmentally friendly, some renewable sources might not hold the answer. Corn-based ethanol, for instance, takes a toll in terms of the cost of production, storage and transportation, which some studies cite as being higher than the cost of gasoline. Still, Thiel believes that comparison won’t matter someday. “We have to look far enough ahead to a time when oil is so scarce that its price is essentially irrelevant,” she says. When bacteria fuel cars, maybe? When farmers live off the grid? When power comes from antifreeze?
It might sound crazy—but three St. Louis researchers are working to make sure it’s not.
