Harvesting seaweed 'forests' and feeding them into large underwater digesters could one day meet the world's energy needs, with nine per cent of the ocean floor being enough to replace fossil fuels entirely, according to an ambitious idea.

 

Even a more immediate and realistic use of seaweed — a major untapped resource — would greatly increase the self-sufficiency and sustainability of small island states, but limited investment is preventing the roll-out of relevant technologies, marine biofuel experts have said.

 

Using wild or farmed seaweed to fuel anaerobic digesters could provide local communities with abundant energy through biogas as well as producing fertilizer, according to Antoine N'Yeurt, a researcher at the Pacific Centre for Environment and Sustainable Development at the University of the South Pacific, Fiji.

 

Anaerobic digestion is a well-established technique that produces methane and a rich by-product ideal for fertilizer by fermenting a range of organic matter.

 

But work was needed to identify the conditions and equipment required to optimize the method for marine biomass, said N'Yeurt.

 

He began a pilot project in Fiji in January — the first attempt to use seaweed for biofuel production in the Pacific region, he said — to achieve just this, using a US$200 digester designed for a family that is ideal for poor and isolated communities.

 

But with much of the US$10,000 grant being spent on laboratory work, he said, more funding was needed if the technology were to become widespread.

 

Small-scale operations are perfect for Pacific islands, according to N'Yeurt, but, along with a collective of professors and researchers called the Ocean Foresters, he sees this technology as having worldwide importance.