ϕ - This is a constant of proportionality that relates voltage and
bacterial population.
Cell A, with an anode-cathode separation 25 mm developed greater
voltage between its electrodes because of small distance in comparison
to the other cells that is B (50 mm) and C (75 mm). The distance
between the cathode and anode determines the speed with which the
electrons are going to travel between the soil layer and therefore the
shorter the distance in a given time, the faster the current and therefore
the higher the voltage. This is similar to results by [23]. From ohms
law, voltage is directly proportional current therefore the voltage would
also increase. Voltage was slightly enhanced on agitation of cell fuel
contents (Figure 4) Agitation ensured evenness in the distribution of
biodegradable material in the cells. The evenness made the material
easily accessible for voltage generation by the bacteria population on
the anode electrode surface.