An investment by The Crown Estate has resulted in a new report, by Maeve Kelly and Symon Dworjanyn of the Scottish Association for Marine Science (SAMS), which reviews the potential of marine biomass, to be anaerobically digested to produce methane which in turn can be used to generate electricity, for heat or for transport.
Marine algae offer a vast renewable energy source for countries around the world that have a suitable coastline available. They are already farmed on a massive scale in the Far East and to a much lesser extent in Europe, primarily in France, and on a research scale in Scotland. Utilising marine as opposed to terrestrial biomass for energy production circumvents the problem of switching agricultural land from food to fuel production. In addition, the production of marine biomass will not be limited by freshwater supplies, another of the contentious issues of increasing terrestrial biofuel production.
Previous studies have shown that marine algae are as good a feedstock for anaerobic digestion (AD) processes as terrestrial sources. Marine algae contain no lignin and little cellulose; demonstrate high conversion efficiencies, rapid conversion rates and good process stability. The residues are suitable for use as nutrient supplements for agriculture.
If marine biomass is to be a serious contender for supplying even a small percentage of our energy needs and if these seaweeds are to be cultured, rather than harvested from the wild, then it has to be accepted that a larger portion of the seas will be ‘farmed’. While culture operations must be subject to their own environmental impact assessment, seaweed farms offer the possibility of increasing local biodiversity as well as removing a proportion of the nutrients which can lead to eutrophication. There is the potential to improve biomass yield and quality through selective plant breeding, and for further mechanisation of the culturing process to streamline production and reduce labour costs.
The report contains 27 prioritised recommendations for further work to establish the true potential of marine macro-algae as a source of biomass.
The report may be downloaded from The Crown Estate website at http://www.thecrownestate.co.uk/mrf_aquaculture.htm
For further information contact: Prof Mike Cowling, The Crown Estate, 16 New Burlington Place, London, W1S 2HX, mike.cowling@thecrownestate.co.uk Tel. 020 7851 5032