Seaweed is a natural complement to our efforts to convert other types of biomass to fuel ethanol. More than half of the dry mass in seaweed is sugar, and the potential is therefore significant.

—Per Falholt, Executive Vice President and CSO of Novozymes

Earlier this month, a team of scientists from Bio Architecture Lab (BAL) in Berkeley, California reported engineering a strain of Eschericia coli to break down and then to ferment alginate—one of the most abundant sugars in brown seaweed, but a sugar that industrial microbes can’t metabolize—into ethanol. Their paper was featured on the cover of the 20 January issue of the journal Science. (Earlier post.)

Seaweed—macroalgae—is one of the world’s fastest growing plants. It does not require irrigation or fertilizers, or take up arable land. Seaweed cultivation is an ancient practice traditionally carried out using long ropes and bamboo rafts. Seaweed can be produced at many locations in the world, but the warm sea conditions, abundant sunlight, and the possibility for several harvest cycles through the year make the waters around India particularly suitable, Novozymes said.

Sea6 Energy has already developed ocean-farming structures that are robust and versatile compared to traditional methods of seaweed cultivation. Focusing first on the geographical constraints of shallow calm seas, required by conventional seaweed farming, Sea6 Energy utilizes proprietary structures for creation of a low-cost seaweed farms on the ocean surface. The structures would allow seaweed to be cultivated in rougher waters, the company says, where it could not be done earlier, potentially opening up vast stretches along coastlines for farming and giving rise to more employment opportunities to rural communities.

In addition, Sea6 Energy is also pioneering approaches to fermenting the sugars derived from seaweed to produce fuel in a manner that requires minimal use of fresh water resources.

Sea6 Energy is currently trialing its cultivation technology in partnership with a few fishing communities around the coastal areas of South India. Novozymes’ Indian arm will work closely with Sea6 Energy to develop the conversion technology.

Sea6 Energy was started by a group of graduates and researchers from IIT Madras.