Abstract

Aquaculture contributed 23.8 million tonnes ofaquatic algae globally in 2012. Increasing consumption ofseaweed (as food, for the production of hydro-colloids, and forproduction of third generation biofuels) will lead to an upwardtrend in its production and cultivation. Aquaculture contributed66.6 million tonnes of fish in 2012, 42 % of global production.Fish demand globally is rising to meet food and nutritionalrequirements; aquaculture for fish will grow. However fishfarms are marred by criticism of pollution caused by dischargeof waste. Integrated multi-trophic aquaculture can reducepollution through co-culture of several species such as seaweedand mussels that utilise waste disposed from fish farms for theirgrowth and development.<br>A model is investigated which would provide 1.25% of energyin transport in the EU from seaweed. This would involve annualproduction of 168Mt of seaweed (in excess of present worldharvest) integrated with 13Mt of farmed salmon. Themodelproposes 2603 anaerobic digesters, each treating 64,500 t/a ofSaccharinalatissima in coastal digesters adjacent to natural gasinfrastructure for downstream use in natural gas vehicles.