Environment & Science

Green slime in your tank: Algae fuel growing in Southern California

"Lightsabers" poke down into a tank of algae to speed its growth before the cell walls of the tiny organisms are weakened and lipids squeezed out for oil.
KPCC/Molly Peterson

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Federal energy officials said this week they're revamping a strategy to develop biofuels – crop-based alternatives to fossil fuels. In Southern California, entrepreneurs are already working to develop fuel from algae.

President Obama didn’t announce a new goal for new fuels this week. Instead, it's a new plan to accomplish an old one. A two-year-old energy law requires the United States to almost triple its production of biodiesel, ethanol, and other fuels more sustainable than oil. "By 2022, we will more than double the amount of biofuels we produce to 36 billion gallons, which will decrease our dependence on foreign oil by hundreds of millions of barrels per year," Obama said. "We're also working to make sure that we can start turning things like plants and woodchips into heat, power, and biofuels."

Now federal agencies will coordinate research, develop pilot projects, and build supply chains for new fuels. The news is welcome to entrepreneurs like Riggs Eckleberry. He jokes that he's growing pond scum. In fact, his company's developing fuel from microorganisms – tiny phytoplankton known as algae.

OriginOil’s offices are about halfway between downtown Los Angeles and L.A. International Airport. It's a small operation &ndash' so's its pilot lab. In a clear tank, algae feed off microscopic bits of carbon dioxide. That fast-growing slurry of algae will mix it up with low-energy light in a second tank.

"That is an empty tank," Eckelberry says. "But it shows you these kind of lightsaber setups which are these long light sticks we've developed ourselves. Very high intensity, high efficiency lighting."

That light helps to grow the tiny algae in water 'til it looks like pea soup. Eckleberry says the idea in this closed system is to deliver as much food and light to the algae as quickly and efficiently as possible. A stirring mechanism keeps the algae moving past lights. "There's a simple paddle here that just keeps the algae turning," he says. "All the culture is rotating around. And the algae gets its chance to really be in on this good energy."

The final step, he says, is squeezing some of the lipids – the fat inside the cells – out of the algae to make oil. Then, what’s left of most of the algae returns to square one. "We tickle the algae but we don't kill it," Eckelberry says. "It’s a milking process. So we keep milking the oil out of the algae without killing it. And then once a day we select about a quarter of the algae to be slaughtered without mercy."

Algae-to-oil research is strong in Southern California. San Diego County's association of governments found last year that algae biofuels generated 270 jobs and $17 million in payroll for the local economy. Eckleberry says that in L.A., OriginOil finds a nexus of money and fabrication shops that feed experimentation. "We have just a tremendous infrastructure for getting things done quick and fast. So the actual experimental iterations here are so easy to do – just go down to Carson and ba-boom, get something done. And you want this welded up? Done."

The science of deriving oil from algae is a developing fast, too. But the tiny plants have long been part of the recipe for fossil fuels, says Chris Reddy. He's a scientist in marine geochemistry who studies fossil and biofuels at the Woods Hole Oceanographic Institute. "Most oil came from algae that lived millions of years ago," Reddy says. "Nature's ahead of the curve on us, we're just trying to giddyup a little."

Reddy likes that, as he says, you can talk to 10 different people and get 10 different ideas for how to make oil out of algae. "You can squeeze it. You can extract it, like extracting flavor out of a coffee bean. You can maybe genetically modify it to give up its fat. Some people are using electricity, putting voltage on it. There's a lot of ways out there."

No one way now dominates. Cost estimates for a gallon of algae-derived fuel range from $30 to hundreds, depending on conditions. At Woods Hole, Reddy's looking for algae that can grow well in cold temperatures. That could save energy and money.

Reddy's intruigued by algae's salad days of research. He says initial data suggest that it's worthwhile to keep trying. "It’s all about scaling and sustainability. You and I can grow algae on our countertop," he says. Still, his view is also buoyed by skepticism. "This project has legs," he says. "But you have to keep in mind there are hurdles."

Southern California startup companies hope to clear those hurdles – and to make a lot of sustainable fuel from algae within the next decade. To meet federal mandates for biofuels, this country may need them to succeed.