Biomara: Sustainable Fuels from Marine Biomass

BioMara is a €6 million four year UK and Irish joint project that examines the feasibility and viability of producing third generation biofuels from marine biomass. Due to high rainfall and poor agricultural land terrestrial biofuel production is restricted in parts of western Scotland, Northern Ireland and Ireland. BioMara aims to contribute to providing these regions - all characterised by long coastlines - with locally produced, renewable, relatively cheap and low-impact fuel that may also support traditional ways of life.

BioMara is ...

• investigating the use of both micro-algae and seaweeds as an alternative to terrestrial agri-fuels like sugar cane, maize, rapeseed, soya and palm
• examining the practicalities of using these aquatic plants as a competitive, sustainable biofuel source
• considering environmental impacts of algal cultivation and extraction
• engaging widely with stakeholders
  

Seaweed cultivation and harvest is an established process in Scotland. Spores are collected and seeded onto strings where they germinate into small plants. These are then transferred to sea where they grow until they are harvested six to eight months later during spring/early summer. Mature seaweeds can be anaerobically digested into methane or fermented into ethanol. We are also collecting seaweeds from around Scotland and Ireland to examine the geographical variation in their chemical composition.

One of the main stumbling blocks for the commercialization of the 'seaweed to biogas' process is the rsistance of algal cell walls to hydrolysis. Pre-treatment of algal biomass to enhance its biodigestibility is key, so the efficiency of various pre-treatments is being assessed by monitring the release of biomolecules from the algal biomas. The most suitable pre-treatments are selected for anaerobic digestion trials. Investigations include the use of environmentally friendly pre-treatment.

Initial work on bioethanol generation focuses on the bacterial breakdown of seaweed into simple sugars.

Development of an Anaerobic Digestion Techno-Economic Model is underway. Effects of homogenising feedstock is being investigated. High ash content of macroalgae is a major disadvantage associated with gasification. Ash chemistry restricts the use of macroalgae for direct combustion and gasification and also reduces the calorific value of the feedstock.

Wild strains of microalgae characterised by high oil content and high stress resistance are being screened to identify those capable of sustained growth in outdoor conditions. Initally these are grown on a small scale in enclosed systems.

200 strains have been selected based on their potential to produce fatty acids required for biodiesel production. Differences in oil content have been found between strains. The effects of varying nutrients and temperature on oil content and growth rates are being studied. Gas chromatography identifies which oils are present while gene probes will help develop tests to confirm when an organism has switched to 'oil production mode'.

Multi-sectoral economic models have been developed for each of the geographic regions forming the focus of our study, probing the potential impacts of biofuels from algae in these areas. A model of the Scottish Western Isles examines the potential economic impacts of seaweed production, and is being expanded to examine alternative impacts from different uses of seaweeds, and alternative scales of seaweed production in the area. The supply chain for biofuel production will be an important factor for the wider economic impacts, and work has begun to identify the key areas for regional economies in securing economic developments from seaweed production.