Vertical farms for crops eliminate the soil microbes that, in the field, help plants grow – UWE Bristol academics are putting the microbes back.
Professor Neil Willey, Dr Mukesh Sharma, and PhD student Segun Ogunmefun are part of a €6 million European Innovation Commission (EIC) project, ‘Microbial Hydroponics (Mi-Hy)’, that is making vertical farms more sustainable by incorporating microbial processes.
In the next few decades Controlled Environment Agriculture (CEA) will produce an even higher proportion of the world’s food than it does now. It will include not just greenhouses but vertical farms and urban agriculture. In CEA crops are frequently grown without soil in a controlled environment with artificial light. In contrast to growing in soil, crops are just fed a nutrient solution (‘hydroponics’) and there’s no microbiome involved in nutrient uptake – a bit like intravenously feeding a human. In the field, the soil around plant roots (the rhizosphere) teems with microbes that help not just nutrient uptake but also stress avoidance and pathogen resistance. When plants in hydroponics have no rhizosphere microbiome, they are completely dependent on inorganic unsustainable sources of nutrients and their taste and nutritional quality can be different. This makes sustainable growth of nutritious crops in hydroponics difficult.
The Mi-Hy project is using wastewater streams to drive Microbial Fuel Cells (MFCs) and Microbial Electrolysis Cells (MECs) and is developing a system to manage them as a prosthetic rhizosphere. This prosthesis captures nutrients from waste, provides energy for lights and pumps, and produces organic compounds like those of the rhizosphere. The project is also developing designs for incorporating this hydroponic system into urban spaces. The plant growth experiments for the project will be done in the UWE Envirotron and the whole system will be demonstrated at, for example, the Sony Computer Science Labs in Paris and the Milan Triannale 2025. Numerous UWE student projects and modules are linked to the research.
Professor Neil Willey commented on the research so far:
We’ve already been able to capture from waste streams more than 50% of the nitrogen that hydroponic plants need so we’re confident that when we’ve made the whole system and can fine-tune it, we will be able to grow plants completely on nitrogen captured from waste streams. We‘re hoping that we might help develop buildings that can feed their inhabitants!
The other partners on the Mi-Hy project are The Dept of Regenerative Architecture at Katholieke Universitaet Leuven , the microbiology labs of the Consejo Superior de Investigaciones Cientificas in Madrid, the Engineering Dept of the University of Southampton, the Sony Computer Science Research Laboratories in Paris and Biofaction in Vienna. Mi-Hy is working closely with 8 other projects to meet the EIC’s €29mi Pathfinder Challenge: Carbon Dioxide and Nitrogen Management and Valorisation.
Professor Neil Willey, Dr Mukesh Sharma, and PhD student Segun Ogunmefun are part of a €6 million European Innovation Commission (EIC) project, ‘Microbial Hydroponics (Mi-Hy)’, that is making vertical farms more sustainable by incorporating microbial processes. They are funded by UKRI under the Horizon Europe Guarantee.
