Rainwater-driven microbial fuel cells for power generation in the remote areas' raw data

The possibility of utilizing rainwater as a sustainable anolyte in an
air-cathode microbial fuel cell is investigated in this study. The results
indicate that the proposed microbial fuel cell can work within a wide
temperature range (from 0 to 30 oC), and under aerobic or anaerobic
conditions. However, the rainwater season has a distinct impact. Under
anaerobic conditions, the summer rainwater achieves a promised open
circuit potential of 553±2 mV without addition of nutrients at the ambient
temperature, while addition of nutrients leads to increase the cell
voltage to 763±3 and 588±2 mV at 30 oC and ambient temperature,
respectively. The maximum open circuit potential for the winter rainwater
(492±1.5 mV) is obtained when the reactor is exposed to the air (aerobic
conditions) at ambient temperature. Furthermore, the winter rainwater
microbial fuel cell generates a maximum power output of 7±0.1 mWm-2 at a
corresponding current density value of 44±0.7 mAm-2 at 30 oC. While, at
the ambient temperature, the maximum output power is obtained with the
summer rainwater (7.2±0.1 mWm-2 at 26±0.5 mAm-2). Moreover, investigation
of the bacterial diversity indicates that lactobacillus sp. is the
dominant electroactive genus in the summer rainwater, while in the winter
rainwater, Staphylococcus sp. is the main electroactive bacteria. The
cyclic voltammetry analysis confirms that the electrons are delivered
directly from the bacterial biofilm to the anode surface and without
mediators. Overall, the study opens a new avenue for utilizing a novel
sustainable type of microbial fuel cell derived by rainwater.