Electricity generation from a floating microbial fuel cell.

A floating microbial fuel cell (FMFC) has been designed and its performance has been evaluated for 153 days. The power output gradually increased to a maximum value of 390 mW/m(3) at 125 days. The polarization resistance of the anode (R(p)(a)) changed with operating time reaching a minimum value at 125 days, while the polarization resistance of the cathode (R(p)(c)) was relatively constant and much smaller than R(p)(a). It has been demonstrated that the observed changes of the internal resistance (R(int)) and the maximum power (P(max)) with exposure time were mainly due to the changes of R(p)(a). Compared with sediment MFCs for which the anode is embedded in marine or river sediments, the application of the FMFC, which could be installed in a buoy, is not limited by the depth of the ocean. The FMFC has the potential to supply electricity to low-power consuming electronic devices at remote locations.