USING DIRECT ALCOHOL FUEL CELLS TO EXTRACT ELECTRICITY FROM ONGOING FERMENTATIONS

摘要

Biomass is a potential sustainable energy source that is widelyrnavailable from waste streams or native ecosystems. However,rncapturing it as an energy source is challenging, especially forrnelectricity generation, because it is often present in dilute streams orrnas hard to use substrates. One promising approach is the conversionrnof biomass to ethanol by yeast and other microorganisms; thisrnbioethanol can be used to produce power in a variety of devices,rnincluding direct alcohol fuel cells (DAFCs). These fuel cells providernclean, quiet power generation and can operate at room temperaturernon the dilute ethanol streams commonly produced from thernfermentation of biomass.1-3 As such there has been considerablerninterest in using bioderived ethanol in DAFCs4-6 but ethanol fromrnfermentations is often extensively purified (e.g. distilled) because it isrndifficult to use this ethanol directly due to various chemicals in thernfermentation poisoning the fuel cells. To fully take advantage of thernbenefits of DAFCs, it would be beneficial to separate ethanol fromrnfermentations with minimal parasitic power losses.