Algenol-Dow tie-up to test direct-to-ethanol process

Florida start-up Algenol Biofuels claims it can efficiently produce commercial quantities of ethanol directly from algae without fresh water and agricultural lands. The company's novel approach has appealed to Midland-based Dow Chemical, the chemical giant that has lent support to it.

The companies recently announced plans to build and operate a pilot plant on 24 acres of land at Dow's extensive Freeport, Texas manufacturing facility. The plant will comprise 3,100 bioreactors, of 4,000 litres capacity each. These would be about five feet wide and 50 feet in length.

The bioreactors are essentially troughs covered by a dome of semitransparent film and filled with seawater. The photosynthetic algae growing inside are exposed to sunlight and supplied a steady stream of carbon dioxide from Dow's chemical production units. The goal is to harness the natural processes to produce 100,000 gallons of ethanol annually.

Algenol is one of the dozens of companies working on ways to produce biofuels from algae but while others are trying to produce biodiesel by harvesting the organism, Algenol is using a different approach. Its process uses genetically enhanced strains of blue-green algae, also called cyanobacteria, to convert the maximum amount of carbon dioxide into ethanol - its process that does away with harvesting of algae to collect the fuel.

Blue-green algae do produce small quantities of ethanol naturally, but only under anaerobic conditions when cyanobacteria are cut off from light or are starved, According to Paul Woods, cofounder and chief executive, Algenol, the company has modified its algae to produce ethanol under sunlight. This happens through photosynthesis first turning the carbon dioxide and water into sugars and later by synthesising those sugars into ethanol by enzymes.

Another point of difference between conventional methods and the Algenol process is that it does not require harvesting of algae for the extraction of ethanol. The elimination of this step not only saves a lot of time and money, it also simplifies the process of biofuel production.