Arizona Public Service and a Massachusetts-based company called GreenFuel Technologies Corp. have launched a project they hope will solve two problems at once — reducing greenhouse-gas emissions from power plants while creating domestic fuel for motor vehicles.
The Emissions-to-Biofuels project at APS’s Redhawk Power Station uses algae that feed on the carbon dioxide produced at the power plant to turn the gas into biodiesel and ethanol fuels
For extra measure, the algae also produce proteins that can be used to as feed for livestock.
The endeavor won the Emission Energy Project of the Year award late Thursday at the eighth-annual Platts Global Energy Awards ceremony in New York. Platts, a division of The McGraw-Hill Companies, reports information on the energy industry.
For the past 18 months GreenFuel has been testing an algae bioreactor system connected to the stacks at the natural gasfired plant at Arlington, about 55 miles west of Phoenix.
Carbon dioxide produced as a by-product of burning natural gas is fed to the algae-unicellular plants that divide and grow by the process of photosynthesis. The hungry algae consume the carbon dioxide in the presence of sunlight, producing oxygen, which is released into the air, and sugar, which is metabolized into lipids, starches and proteins.
The algae biomass is then harvested, and the lipids, an oil, are converted into biodiesel fuel, and the starches are turned into ethanol. Both could be used as fuels for motor vehicles, or they could be recycled for burning in the power plant to produce more electricity.
Carbon dioxide is a colorless gas scientists believe is primarily responsible for the greenhouse effect that is producing global warming.
The algae are capable of absorbing more than 80 percent of the carbon emissions produced by the Redhawk plant during daylight hours, said APS spokesman Steven Gotfried.
If every natural gas power plant in Maricopa County were equipped with an algae bioreactor, every car in the county could run on the resulting fuels for about five months, according to APS and GreenFuel calculations.
“This is the first time ever that algae biomass created on-site by direct connection to a commercial power plant has been successfully converted to both these biofuels,” said Isaac Berzin, GreenFuel’s founder and chief technology officer. “The conversion and certification of the fuels were conducted by respected, independent laboratories.”
The technology was previously tested on a laboratory scale at the Massachusetts Institute of Technology, but the Redhawk plant was the first site where it was tested on a power-plant scale. The next step will be to expand the operation to determine if the process is commercially viable, Gotfried said. GreenFuel expects to start growing algae on one-third of an acre next to the power plant, perhaps as soon as January, he said. Also the companies will seek markets for the biofuels.