By Rubina Obaid
From seaweed one could produce five times ethanol productivity than corn and sugar cane that too require proper cultivation area and fresh water. However, seaweed can be grown in salty water and also with the rapid pace and low maintenance. It contains significant amount of polysaccharides paired with low lignin content that makes it a perfect candidate for bioconversion to ethanol. The research has been conducted by Advanced Research Project Agency-Energy (ARPA-E) under the program known as Macro algae Research Inspiring Novel Energy Resources. A breakthrough of breaking down sugar in seaweed may make abundant central of replacing fossil fuels as the form of sugar inside the seaweed is really exotic.
There is a long way to materialize the concept, but it is considered as one of the most reliable , cleaner and large scale replacement sources for resource intensive ethanol. Seaweed is an ideal option as it doesn’t require watering, maintenance or fertilizers and nutrients are drawn through water and grown naturally. Scientists also discovered iodine while processing seaweed. Until now seaweed farms are more structural and closer to shore and the objective of huge offshore seaweed farm is also under consideration to provide biomass that can be used to produce sufficient bio energy. Huge pallets of seaweeds will be cycled from these farms from the surface to underwater to make sure they get adequate nutrients.
The MARINER program along with dozens of other organizations and private companies making different ideas of giant seaweed farms which would also be responsive to weather threats and other hazards. MARINER has developed the best tool with which more remote farms will be built in larger scale to expand much larger portion of markets for renewable biomass energy. MARINER explains that currently seaweed and macro algae are mainly used as food for human consumption. Yet, there is a great opportunity that seaweed are also going to be used as feedstock for fuels and chemicals.
Bio energy option in U.S. is dominated by corn based ethanol which is also becoming the cause of pollution and attached with multiple monetary and nonmonetary costs. In Asia various countries are cultivating seaweed for a long time but comparatively in smaller scale so in order to use seaweed as the option of bio energy and bio fuel researchers would have to scale up the production by using advance technology for massive cost effective production for commercial use. This would be able to supply fuel for aviation and other transportation mode that wouldn’t be electrified to reach decarbonization.
Building big seaweed farms in the middle of pacific ocean is being carried out by Marine Bio Energy, to address a key problem with the macro-algae farming concept. As the top layer of the ocean has more sunlight and less nutrients whereas in deeper layers there are more nutrients but less sunlight, due to this arrangement large scale seaweed cannot be grown on their own . Hence Marine Bio Energy found a solution that it will try cultivating seaweed on farms which are attached to submarine drones. The farm would spread on couple of hectares and would consist upon rows upon rows seaweeds. The farms will be dragged under water through drones at night to provide nutrients. Every few months drones would pull the farm to harvesting location.
Significant amount of energy can be obtained by deploying sufficient seaweed farms in the ocean, it has been predicted by Cindy Wilcox, co founder and president of Marine Bio energy. “To replace 10% of liquid petroleum fuels used in the U.S. today, we would need to have an area under cultivation about the size of Utah” she added “The room in the pacific is of 705 Utahs. ” The company is in its initial stages of testing the idea and found encouraging results as the depth cycled kelp grew better than the control group which was kept at a single depth. Researchers of Marine Bio Energy are planning to conduct similar kind of experiment which is tentatively scheduled in April.