Can seaweed become the "Corn of the Sea" crop for biofuel production? Perhaps. 'Get biofuel crops off the land and into the sea,' is the rallying cry of Ricardo Radulovich, director of the Sea Gardens Project at the University of Costa Rica. He is talking not about harvesting natural "seaweed," but of cultivation.
Until now, seaweed has been valued mainly as food, but also as fertilizer, animal feed, and recently for a growing phycocolloid industry producing algin, agar and carrageenan. But it could also be a major fuel.
Macro-algae (seaweeds) are cultivated at sea, mainly by simply tying them to anchored floating lines. Seaweeds do not require soil, and are already provided with all the water they need, a major advantage over land production of biofuels since water is the most limiting factor for most agricultural expansion, especially with climate change.The International Seaweed Association (ISA) has been recently formed. They may be able to deal with some of issues mentioned below. ISA have a very nice photo gallery that is worth your time.
Mariculture biofuel risk management issues summary:
Much more than technology is at stake.
Little mentioned in the print and online media are prospective labor questions for mariculture (on the indicated scale). Mariculture is labor intensive. It is typically done in poor nations, near sheltered archipelagos or on the leeward sides of island nations, and can offer great opportunities for economic development, often as family run enterprises. However, we don't want to fuel the world's SUV's on the backs women and children.
Sheltered archipelagos are at risk from ocean level rise, per long term climate model predictions.
And, there will be competition for marine habitat, just as there is for wildlife habitat on marginal farmland, once biofuel production scales up "under the sea."
We have to know more about supply chains, too, before this is pronounced "Green."