• Project Background

Project Background

The need for biofuels and the benefits of using seaweed biomass

Bioenergy production is currently of great interest in Europe and the Commission of the European Communities has set out in its document (Communication from the Commission - an EU Strategy for Biofuels {SEC (2006) 142}/* COM/2006/0034 final */) A SEVEN POLICY AXES on BIOFUEL STRATEGY including:

1. Stimulating demand for biofuels

2. Capturing environmental benefits

3. Developing the production and distribution of biofuels

4. Expanding feedstock supplies

5. Enhancing trade opportunities

6. Supporting developing countries

7. Supporting research and development

As well as promoting the use of biofuels in transport the Commission also wishes to encourage the use of biofuels for electricity generation and heating (Renewable energy: European Commission proposes ambitious biomass and biofuels action plan and calls on Member States to do more for green electricity. IP/05/1546) 

These policies have been introduced for several reasons:

  • Our current dependence on fossil fuels for energy generation is not sustainable.
  • Fossil fuels such as crude oil, natural gas or coal are non-renewable.
  • The demand is continuously increasing and will continue to do so as economic growth continues. However, the supplies are limited and the discovery of new reserves does not match the increasing needs.

The energy industries have an opportunity to offset the projected decline in Scotland’s and the rest of the EU’s domestic offshore Oil & Gas industry by increasing business growth in renewable energy industries for the global market. There is a global increase in demand for energy. Demand for oil is forecast to grow by 65% by 2030, while demand for coal, gas and renewable energies are all predicted to double in this period. The International Energy Agency forecasts expenditure of around £300 billion per annum to meet demand and develop the required infrastructure.

Furthermore, burning fossil fuels leads to a net increase in atmospheric carbon dioxide, a greenhouse gas which is very likely contributing to the global warming process that is of growing concern. Current demands require energy sources that are sustainable, cheap and non-polluting. It seems unlikely that a single energy source will solve all of these problems in the future, which suggests that diversification is the best solution.

Modern technologies, and biotechnology in particular, are making great efforts to transform biomass from diverse sources into compounds that can serve as efficient biofuels and can be produced economically and in sufficient quantities to replace crude oils. Combusting these biomass-derived biofuels will only release to the atmosphere CO2 that had been previously fixed by photosynthesis, and will be taken up by the next round of photosynthesis in growing crops, which makes them neutral from the point of view of global warming. In addition, biomass would be a renewable and sustainable source of fuels. However, the need for biomass for biofuel production could potentially compete with already hard-pressed food-crop production. It is necessary therefore to consider non-food crop biomass.

Seaweeds represent such an option with many benefits:

- Seaweeds are for 2nd and 3d generation biofuels:

  • A Biomass with no competition for food/fodder, land and irrigation water
  • No lignin
  • Possible sources are beachcast community scale, natural harvest and large scale MariCulture industrial scale.

- Seaweeds for biofuels/chemical feedstock and biopharma

  • Too wet for pyrolysis or direct burning
  • A biomass  for anaerobic digestion (AD)  - methane

 AD stages

A mixed microbial species fermentation platform

Brown seaweeds are naturally abundant in Scotland, especially in the Hebrides and Orkney Islands. They are also beachcast during storms all around the coast and the potential for seaweed culture needs to be investigated for all coastline areas, in line with the concept of minimising transport costs and reducing the carbon footprint for seaweed biofuels and biorefinary production.


Problems with Seaweed AD

  1. Over acidification

Brown Seaweeds have high levels of sugars

-          Demands low feed rates or

-          Two stage AD:

  • Overcomes sensitivity to acidity and incompatible slow generation times for acetogenic methanogens
  • Offers  possibility of methane (from hydrogenotrophics in phase I) and other biofuels/chemicals from phase II acetate
  1. AD inhibitors: Polyphenols, sulphated polysaccharides - both are particularly in the Fucaceae :

-          Ascophyllum nodosum and Fucus spp. But, these are the only seaweeds currently harvestable in Scotland