SEE Algae Technology of Austria, is building a 2.5-acre factory on a sugar plantation near Recife, Brazil, that will use genetically modified algae that can eat carbon dioxide from the sugar. Adding urea and some nutrients, the algae excrete ethanol.

The path to profitability, according to the company, is raising the amount of algae produced per unit of area. Algae grows in ponds, but that turns out to require a lot of space: sunlight does not penetrate more than a couple of inches, so the ponds must have big surfaces. The problem is that the carbon dioxide injected to promote algae growth tends to escape from a big surface.

SEE Algae’s solution is a silo that is 16 feet tall and has a volume of 177 cubic feet. Sunlight is directed all over the inside of the silo by optical fiber technology.  Rest of this NY Times article