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Journal of Chinese
Architecture and Urbanism Microbial technologies: Toward a regenerative architecture

not been widely used as they are neither competitive with between microbial metabolisms and digital systems
fossil fuels, nor renewables as a single source of electrical (screens, light-emitting diodes [LEDs], USB ports, etc.)
energy. Over the last two decades, MFCs have largely gained through electron transfer, the bio-digital interface mediates
traction as a source of bioremediating green energy due the direct relay of MFC outputs (electrons, data, and
to breakthrough advancements, which are predominantly chemical transformation) from an organic environmental
confined to the laboratory. Field/pilot trials for the platform (microbes) to low-power electronic devices.
treatment of wastewater streams, such as urine, greywater, As the production of electrons by the biofilm are based
and blackwater, by MFC stacks have increased in number, on metabolic reactions, alterations in electron transport
®
for example, Pee Power urinals (Walter et al., 2018) and and carbon metabolism can also influence bioelectricity
Urine-tricity (Oxfam International, 2015), but further production, establishing the potential for two-way electro-
research and development is still needed to advance the biochemical exchanges between human and microbe,
technology’s commercial readiness for novel applications which are based on an electron economy to establish
such as smart toilets and ultimately, installation within the principles of a human/microbial trading system. The
ecohomes. At scale, pilots engaging MFCs (such as in following precedents offer a series of case studies based on
the brewing industry) are at relatively immature stages working MFC prototypes for building systems organized
of development, so their potential impacts are cautiously in different configurations, which were developed for
reported (Singh & Sharma, 2010). metabolic trading systems that operate at low-power
thresholds of around 2–3 V, generated by 15 MFC units.
7. Bioelectricity for building operations 9. Living Architecture
Although a vast range of microbially mediated processes
are of value to households and industry, to date, the The Living Architecture project is a “living” combined
electrical outputs of bioreactors have generally been too utilities infrastructure that uses 15 MFC complexes
5
weak to drive conventional electronic hardware (Koffi & consisting of four chambers, to turn liquid household
Okabe, 2020). While MFCs cannot compete with the sheer waste, such as urine and greywater, into valuable resources
power provided by other electricity generating systems (electricity, biomass, water, reclaiming phosphate from
(renewables and fossil-fuels), their (material) circularity washing-up liquids, and removing poisonous gases from
is unsurpassed, providing a circular flow of resources the air) that can be reused in the household (Armstrong
within a household or building, which are metabolically et al., 2017) (Figure 3).
constrained by the carrying capacity of the site. Part of the
challenge for MFCs becoming a household system is that
innovation in electrical appliances for the last 150 years
has effectively operated within a conceptual frame where
energy is unlimited and can be used to solve all challenges
from refrigeration to climbing stairs, resulting in the voltage
outputs for modern homes being standardized for 230V.
Despite current innovation outputs being benchmarked
against industrial expectations, significant advances in
biotechnology, material sciences, and hardware design are
creating the context for the installation of smaller, lighter,
and more efficient MFCs that are currently being trialed
in wastewater processing, enabling their installation in
buildings. This new generation of MFCs benefits greatly
from their compatibility with low-powered digital
technologies, meaning they use energy in a much smarter Figure 3. Detail of the fully inoculated Living Architecture “wall” and
way than other energy source through the juxtaposition of apparatus installed at the University of the West of England, Bristol, the
organic and “smart” (electronic) platforms that is mediated Living Architecture project, 2019. Source: Photography courtesy of Rolf
by biofilms at the bio-digital interface. Hughes.

8. Introducing the bio-digital realm
5 These chambers comprise two MFCs separated by two
The bio-digital interface is located at the MFC electrodes photobioreactors separated by ceramic plates that enable the
where the organic and electronic domains meet through different resident microbial systems to exchange nutrients
biofilm attachment. Making an intrinsic connection between their respective populations.

Volume 5 Issue 1 (2023) 5 https://doi.org/10.36922/jcau.157