With exhausting fossil fuels and increasing greenhouse gas emissions, numerous attempts, to overcome future energy challenges, are being pursued. In this study, small-scale microbial fuel cells (MFCs, 0.7mL anodic chamber volume) were built to investigate their electrical performance with uric salts as fuel for power generation. When uric salts were added to other substrates such as urine or sewage sludge, results showed improved power generation and longevity. The small-scale MFCs produced a comparable amount of power output (PMAX: 11.09mW/m2; 44.36W/m3) to that produced by larger MFCs, which suggests that MFC miniaturisation and multiplication is a sound approach for scale-up and practical implementation. © 2014 Elsevier Ltd.