Fig. 4From: Scaling-up of a novel, simplified MFC stack based on a self-stratifying urine columnPower produced by a stack of six MFCs connected in parallel. Data illustrate the influence of the feeding regime on the stack behaviour. The resistive load was 40 Ω. Asterisk indicates that the stack was manually replenished twice during the same day. The power drop from day 2 to 3 was due to the drowning of the cathode (mechanical blockage)Back to article page