We launched the EAB culture and started monitoring the current produced from metabolic acetate oxidation. The current increased continuously during EAB maturation, reaching a current density of approximately 2 A m -2 after 1 month. According to some reports, this corresponds to an early-stage EAB growth state, though ours arrived at this value later than others. We then began to perturb the EAB with different temperature pulses to induce changes to the rate constants that govern the output currents. Generally, the optimal operating temperature for BES is around 25-35°C. Exposure to temperatures outside this range may result in non-repeatable behaviour due to cell death or changes to EAB material properties (phase, mechanical moduli). Therefore, we relied on the accurate temperature control system to confine temperatures in this range to ensure a safe, reversible operation of the EAB. The duration of the applied temperature pulses was between 45 and 60 minutes, based on the heat/cool rates of the system and the PID controller. Based on preliminary experiments, this was enough time for the gradual heating to arrive at the setpoint without overshooting or ringing. The temperature modulations were done on very mature EABs which were in equilibrium on the order of the timescale of the experiments. As well, the reported doubling time for G. sulfurreducens is over 6 hours, therefore, the temperature pulse time was too short for the EAB to become acclimated to the elevated temperatures. After 1 month, we started experiments under varied temperature and concentration. Figures This process was repeated to obtain measurements at 4 to 7 temperature setpoints for individual combinations of flow rate (Q=0.5 and 2 mL h -1 ) and concentration ([Ac]=10, 7 and 5 mM) while the EAB was 1 month old. After the EAB reached 4 months old and the current at standard operating conditions (0.5 mL h -1 of a 10 mM acetate nutrient solution) reached 4 A m -2 , the entire experimental process was again repeated. We chose these two EAB ages based on their current density in order to match previous definitions of young and mature growth stages of a pure-culture G. sulfurreducens EAB in an MFC. To extract the kinetic parameters from the 1-month and 4-month EAB data, we plotted the current/temperature data in its Arrhenius form (equation 3, with n=8) for experiments under flow rates of 0.5 mL h -1 (Figure ) and 2 mL h -1 (Figure ). As observed in Figure , the trends were linear, as expected from Arrhenius theory, and consisted of a single slope. These data were fit to a linear regression model, and the fitting error was recorded to obtain confidence intervals in the slopes and y-intercepts. The activation energy was obtained directly from the slope (EA/R), and the y-intercept produced ln(A•p), as defined in equation 3. We plot the extracted EA eff values in Figures and, respectively. The EA eff values after 1 month were measured to be between 17 and 22 kJ mol -1 , with the value slightly higher at low flow rate (0.5 mL h -1 ) compared to values obtained at high flow rate (2 mL h -1 ). Significantly higher EA eff values were measured after 4 months, ranging between 27 (at 0.5 mL h -1 ) and 40 kJ mol -1 (at 2 mL h -1 ). The y-intercepts from the Arrhenius plots, which reveal details pertaining to the governing kinetic model and the pre-exponential factor with proportionality constant (A•p), are shown in Figure .