The scalability of bioelectrochemical systems is a key parameter for their practical implementation in the real-world. Up until now, only urine-fed self-stratifying microbial fuel cells (SSM-MFCs) have been shown to be scalable in width and length with limited power density losses. For practical reasons, the present work focuses on the scalability of SSM-MFCs in the one dimension that has not yet been investigated, namely height. Three different height conditions were considered (1 cm, 2 cm and 3 cm tall electrodes). The normalised power density of the 2 cm and 3 cm conditions were similar either during the durability test under a hydraulic retention time of ≈39 h (i.e. 15.74 ± 0.99 μW.cm⁻³) and during the polarisation experiments (i.e. 27.79 ± 0.92 μW.cm⁻³). Conversely, the 1 cm condition had lower power densities of 11.23 ± 0.07 μW.cm⁻³ and 17.73 ± 3.94 μW.cm⁻³ both during the durability test and the polarisation experiment, respectively. These results confirm that SSM-MFCs can be scaled in all 3 dimensions with minimal power density losses, with a minimum height threshold for the electrode comprised between 1 cm and 2 cm.

生物电化学系统的可扩展性是其在现实世界中实际实施的关键参数。到目前为止，只有尿液喂养的自分层微生物燃料电池 (SSM-MFC) 已被证明在宽度和长度上是可扩展的，并且功率密度损失有限。出于实际原因，目前的工作侧重于 SSM-MFC 在尚未研究的一个维度（即高度）中的可扩展性。考虑了三种不同的高度条件（1 厘米、2 厘米和 3 厘米高的电极）。2 cm 和 3 cm 条件下的归一化功率密度在 ≈ 39 h 的水力停留时间（即 15.74 ± 0.99 μW.cm ^-3）下的耐久性测试期间和极化实验期间（即 27.79 ± 0.92 μW）是相似的.cm ^-3）。相反，在耐久性测试和极化实验期间，1 cm 条件下的功率密度分别较低，分别为 11.23 ± 0.07 μW.cm ^-3和 17.73 ± 3.94 μW.cm ^{-3 。}这些结果证实，SSM-MFC 可以在所有 3 个维度上缩放，功率密度损失最小，电极的最小高度阈值介于 1 厘米和 2 厘米之间。