By CELESTE BAUMGARTNER
WOOSTER, Ohio — Deep green, murky water is constantly pushed along by paddlewheels in four 30-by-200-foot ponds at Cedar Lane Farm. The ponds are growing algae for collaborative bioenergy research by Touchstone Research Laboratory based in West Virginia, and the Ohio Agricultural Research and Development Center (OARDC).
This research involves testing of several innovative technologies, with the goal of making algae farming more cost-effective and sustainable in a wider variety of climates and locations. It is funded by grants from the U.S. Department of Energy (DOE) and the Ohio Coal Development Office.
Two of the four ponds, which are shaped like auto raceway circuits, are outside and two are inside the greenhouse, which allows for testing under different conditions, said Dr. Yebo Li, OARDC biosystems engineer.
One of the new technologies for growing algae involves bubbling carbon dioxide (CO2) from Cedar Lane Farm’s coal-fired boiler into the ponds, Li said.
“We want to see how much CO2 can be trapped and used to grow algae,” he explained. “That keeps the CO2 from escaping into the air. We also plan to feed the algae with anaerobic digestion effluent which contains the nitrogen and phosphorous, nutrients needed by the algae.”
Algae is similar to any other plant in that it uses CO2 during photosynthesis, so it essentially converts the gas into biomass to grow, said Philip Lane, Ph.D., program manager for Touchstone.
“We grow the algae, then we extract the oil from the algae,” Lane said. “We are left with two things; one is the algae oil that we will then convert to biofuel, whether it is biodiesel or jet fuel, then we have the de-oiled algae part, the biomass.”
That biomass is part of Li’s research, which involves using it as a feedstock for anaerobic digesting, Lane said. This helps boost the production of biogas, which can be converted to electricity, compressed natural gas (CNG) or liquid hydrocarbon fuels.
“Algae biomass is rich in proteins and carbohydrates and works very well for anaerobic digestion,” Li said. “Algae contain about 40 percent lipids and 60 percent biomass, so future large-scale algae farming would generate a lot of biomass residue that can be used as a fertilizer or bioenergy feedstock.”
Li also said an acre of algae can produce as much oil as 10 acres of soybeans.
Yet another part of the research involves a new technology, previously developed by Touchstone, called a phase-change material that could improve the economics of algae farming, Lane said.
“You can think of it as a covering over the pond,” he added. “We’re trying to improve the growth of algae in that pond by using this material. It’s an actual liquid layer that floats on the surface.”
One of the problems with growing in an outside, open pond is that much water is lost to evaporation, Lane said. That can get expensive. This material reduces water loss to evaporation. It also controls the infiltration of invasive species.
“The other thing that we’re trying to do is to help stabilize the temperature of the water, so it doesn’t fluctuate so much through day- and nighttime temperature cycles. Any of those things will hopefully result in positive effects on algae growth.”
The DOE recently issued a call for more algae studies, Lane said. Touchstone was notified it was one of the winners of a $15 million DOE program. It will be part of a team led by Arizona State University, a world leader in algae research. The ponds at Wooster will be used in that research.
The DOE wanted to have regional testbed facilities, so there would be several testbeds in different regions of the country all doing preprogrammed, unified studies growing algae, Lane said.
“All of the places will have the ability to grow algae at a meaningful scale,” Lane said. “We will be providing access to different parts of the algae industry that want to test their equipment. For example, they may need a source of algae to test their processing equipment; they may have a strain of algae that they want to test and a large-scale facility would be prohibitive to build.”
This part of the project is to help facilitate and make accessible an algae growing facility on a scale larger than a laboratory, so different companies and people have access to it, to try to further develop and push along algae technologies.
Algae farms – how soon?
So just how soon will algae be a viable crop? “If we’re just talking biofuels, we’re going to need some technology breakthroughs, to really make it cost competitive with current fuel prices,” Lane said.
“We’re probably three to five years away from that, and I think that is pretty optimistic.”
However, different strains of algae produce different types of oils, he said. Several algae strains will produce high-value components such as Omega 3 materials. Those are high-value products that could be exploited now.
“Just in terms of biofuels, we’re several years off,” Lane said. “But if you use the high-value components – including seed supplements and food supplements, which would be the major money-maker – then use other components for fuel, that you could do at any time.”