Plant Microbial Fuel Cells; a new marine energy source

Worldwide there is need for more clean, renewable, sustainable energy. Plant microbial fuel cells (Plant- MFCs) generate in-situ green electricity(Strik, Hamelers et al. 2008). How does this work? By photosynthesis the plant is capturing solar energy which is transformed into chemical energy as organic matter. Easily 20 to 40% of this organic matter is released via the plant roots into the bioanode of the microbial fuel cell. At the anode electrochemically active oxidise the organic matter while using the carbon anode electrode as final electron acceptor. The released electrons flow via energy harvester to the cathode were typically oxygen is reduced. Under Western European weather conditions a power output of 3.2 W/m2 is expected which is up to 10 times higher than conventional biomass electricity systems (Strik, Timmers et al. 2011). At this moment the Plant-MFCs long term power output is 50 mW/m2 which is attractive for powering sensors or LEDs (Timmers, Strik et al. 2010). To achieve more plantpower larger areas are needed. Plants in Plant-MFCs grown under waterlogged conditions to support the preferred conditions in the anode. Therefore it's interesting to integrate Plant-MFCs into salt marsh wetlands as these are widely present. In Western Europe salt marshes, common cord-grass (Spartina anglica) is one of the dominant species (Roberts and Pullin 2008). Spartina anglica is used as one of the model plants in the Plant-MFC. The objective of the presentation is to give an overview of recent results of Spartina anglica Plant-MFCs and show the identified challenges to improve system performance. Lab scale experiments and model work was performed. Discussed will be the value of the technology and challenges to introduce a Plant-MFC into marine ecosystems