Turning the home into a circular lab: what Mi-Hy proposes and why it matters

At the 2025 EIC Summit Rachel Armstrong, professor of regenerative architecture at KU Leuven and coordinator of the EIC Pathfinder Mi-Hy project, outlined an ambition that is deliberately modest in scale but broad in implication. Mi-Hy seeks to reintroduce substantive productive processes into the home by combining Microbial Fuel Cells and hydroponics to create an engineered root zone that converts waste carbon and nitrogen into plant biomass. The project's narrative is framed around household inputs such as wastewater and atmospheric CO2 and an aspiration to make urban food production greener and more circular.

Project goals, inputs and the idea of a prosthetic rhizosphere

Mi-Hy aims to demonstrate routes for CO2 utilisation via microbial reactions and to show how household wastewater can feed hydroponic systems while recovering nitrogen and mobilising phosphorus. The ambition is to reduce or avoid conventional synthetic fertilisers and to create a modular platform that could be used in home hydroponics or scaled to industrial greenhouses. The project is supported by the EIC Pathfinder scheme, which funds high-risk, exploratory research with the potential for disruptive outcomes.

Core technologies and consortium capabilities

Mi-Hy explicitly mixes disciplines to address a systems problem. Partners bring expertise in microbial fuel cells, electronic monitoring and precision gardening, nitrogen biochemistry, science communication and prototyping. Armstrong highlighted collaborators such as Sony CSL Paris for green electronics and precision gardening, Yannis Ieropoulos and the University of Southampton for MFC expertise, the Spanish National Research Council (CSIC) for nitrogen metabolism and biofilm engineering, and BioFaction for public engagement and dissemination.

Cross-project collaboration and the role of monitoring

Mi-Hy has already begun collaboration with CONFETI, another EIC Pathfinder project, in events held at the Universitat Autònoma de Barcelona. That collaboration is practical. CONFETI has a 50-channel chip capable of gathering detailed electrochemical signals from MFCs and related devices. Integrating that monitoring capability could make Mi-Hy systems far more instrumented and data-rich, enabling better control of microbial communities and performance testing.

Ambitions versus technical and market challenges

Armstrong painted a picture that spans household modules to industrial farms in Almeria. She mentioned speculative plug-ins such as a solar device that could process washing machine wastewater into a detergent precursor. Those kinds of claims are useful to stimulate imagination but they are not technical deliverables of Mi-Hy at this stage. The project is exploratory and its work focuses on proof of concept for microbial CO2 utilisation, nitrogen recovery and plant performance in engineered rhizospheres.

EIC context and why interdisciplinary teams are central

Mi-Hy is funded under the EIC Pathfinder instrument which is designed to support high-risk, high-reward scientific advances. The EIC often groups complementary Pathfinder projects into portfolios to encourage collaboration and technology cross-fertilisation. Armstrong argued that solving problems such as carbon and nitrogen valorisation requires many insertion points across different sectors and technologies. The involvement of corporate research labs, national research councils and SMEs follows the EIC practice of building consortia that combine lab know-how, industrial perspective and communication skills to accelerate uptake.

What to watch for over the project timeline

Mi-Hy runs as a Pathfinder project with work expected through 2027. Early indicators of progress to look for are peer reviewed publications on engineered biofilms and CO2-to-biomass pathways, independent validation of nitrogen recovery rates from real household wastewater, demonstration trials in controlled hydroponic setups and data from instrumented MFC arrays enabled by chips such as the one developed by CONFETI. Equally important will be documented assessments of energy input versus nutrient output and biosafety protocols for any household-facing deployments.

Signs of responsible development

Mi-Hy includes a science communication partner and has emphasised distributing knowledge to students and entrepreneurs. That is a welcome part of responsible innovation. Public engagement, transparent reporting and preparation for regulatory review are essential if biological systems are to move closer to consumer settings.

Takeaways and a critical reading of the promises

Mi-Hy is an interesting combination of mature techniques and speculative system design. Microbial Fuel Cells are an established research area and hydroponics is a mature agricultural technology. Combining them with engineered rhizospheres and advanced monitoring is a plausible research program and one well suited to EIC Pathfinder funding. However the narrative linking household wastewater to fully self-contained, maintenance-free circular home appliances remains aspirational. The path to market will require sustained demonstration, regulatory clarity, maintenance models for citizens and evidence that the overall environmental and energy balances are positive at scale.

For policy makers and funders the project highlights how the EIC seeks to create fertile ground for new markets by funding interdisciplinary consortia and cross-project collaboration. For entrepreneurs and corporates it illustrates the need to couple laboratory innovation with monitoring tools, procurement partnerships and user-centred design earlier in development. For the public the project offers a compelling vision of greener urban food systems but also an important reminder that many research milestones must be achieved before household circularity becomes commonplace.

Further information and resources referenced by the project include the Horizon Europe project database and the Mi-Hy project website. A recording of Rachel Armstrong's EIC Summit 2025 presentation is available through EIC Summit materials for those who want to hear the primary testimony directly.