The microalgae in the pond — at its peak — can produce more oil than the soybean, canola and safflower plant, Shurtleff noted.
VERNAL — Researchers at Utah State University are making progress on a project that could soon have drivers filling up their gas tanks with fuel harvested from pond scum.
The project has moved from USU’s Logan campus to Vernal — the heart of the state’s oil and natural gas industry.
“We saw it as an opportunity to demonstrate the concept of our floating algae pond, or our pond within a pond, where we use water to grow algae at high enough densities to where it makes sense to harvest it and then convert it into fuels and other bio-products,” said Kevin Shurtleff with Utah State’s Energy Dynamics Laboratory.
Shurtleff and his team spent six weeks building the floating pond on dry land before submerging it in the drainage pond that holds runoff water from the USU’s campus in Vernal.
“There’s just not enough land or not enough capability in Logan to do large scale algae projects,” Shurtleff said. “Our goal is to do very large-scale, low-cost algae projects for biofuels.”
Despite its size, the floating pond is portable. It will be moved within the next few weeks to a wastewater treatment facility in southern Utah to ride out the winter. Such portability is a key component of the project, Shurtleff said.
“The goal is to put thousands of these floating ponds in the ocean or on coastal waters where there’s plenty of room, there’s plenty of sunshine, there’s plenty of water, and it’s unused for the most part,” he said.
The microalgae in the pond — at its peak — can produce more oil than the soybean, canola and safflower plant, Shurtleff noted. One acre of soybeans, for instance, produces a maximum of about 60 gallons of fuel annually.
“This one-acre pond should produce anywhere from 1,400 to 2,000 to 3,000 gallons (of fuel) per year,” Shurtleff said.
The pond in Vernal lacks the requisite nutrients for optimal production, so a technician adds those nutrients twice daily. Oxygen levels in the water and the amount of sunlight the pond receives are also closely monitored.
Once it’s harvested, the algae from the pond is spread on plastic and allowed to air dry for 24 hours before being milled into a green powder. Then the oil is extracted from the powder and converted to biodiesel.
“Most people, you know, they think of pond scum as the green algae that’s growing in their swimming pool. They don’t like it,” he added. “But around us, in our team, pond scum is a compliment. There’s no higher praise than to be called pond scum.”
Researchers hope to produce enough biodiesel in the near future to take it for a test drive.
“I get the first tank of biodiesel that we produce from the algae that we grew,” Shurtleff said with a laugh.