Royal Agricultural University Researchers Advancing Plasma‑Activated Water (PAW) for Sustainable Agriculture
By Dr. R. Ramkissoon (freelance journalist)
Photos by Paul Nicolls
Agriculture relies heavily on water, yet the runoff that leaves fields after irrigation often carries a complex mixture of fertilisers, organic matter, microbes, and chemical residues. Managing this wastewater is a growing challenge, particularly as farming systems face increasing pressure to reduce pollution, conserve water, and operate more sustainably. Traditional treatment methods can be costly, energy‑intensive, or insufficient for removing certain contaminants. In response, researchers at the Royal Agricultural University (RAU), Cirencester Campus and Swindon Hub, England, UK are exploring an innovative alternative: the use of cold plasma technology to transform agricultural wastewater into Plasma‑Activated Water (PAW) — a treated water source that not only becomes safer but can also enhance plant growth.
Within the RAU’s Water, Energy and Environmental Engineering (WEEE) Research Cluster, led by British-Trinidadian Professor Kiran Tota‑Maharaj, with support from Dr. Obafemi Obajemihi, and doctoral researcher Muhammed Faruk Hossain are all developing and leading on this pioneering research project. Their applied ecological engineering/ environmental engineering research focuses on developing practical, environmentally responsible solutions that help farmers reuse water more efficiently while reducing the environmental footprint of agricultural operations. By investigating cold plasma as a treatment method, the team is contributing to a new generation of sustainable water technologies.
Cold plasma, sometimes described as “energised air,” is a partially ionised gas containing highly reactive particles. Unlike thermal plasma, it operates at low temperatures, making it safe for use with water and biological materials. When cold plasma interacts with agricultural wastewater, it generates reactive oxygen and nitrogen species capable of breaking down chemical pollutants, inactivating harmful microorganisms, and altering the water’s chemistry in beneficial ways. The process can be visualised as a controlled, miniature lightning‑like reaction that cleans the water without the need for chemical additives.
To produce PAW, the RAU research team led by Prof Kiran Tota-Maharaj first collects wastewater from agricultural sources. This water is then exposed to cold plasma within a specialised reactor. As the plasma interacts with the water, it triggers a series of reactions that degrade contaminants and create a solution enriched with reactive species. The result is a cleaner, safer water source with enhanced properties that can support plant development. Studies have shown that PAW can improve seed germination, strengthen root systems, and reduce the incidence of plant diseases. It may also decrease the need for chemical fertilisers, offering both economic and environmental benefits.
The significance of this research extends beyond water treatment. As global demand for food increases and climate pressures intensify, agriculture must adopt technologies that conserve resources and minimise environmental harm. PAW offers a dual advantage: it provides a method for treating wastewater without chemicals and simultaneously enhances plant growth. This aligns with broader sustainability goals and supports the transition toward more resilient farming systems.
Prof. Tota‑Maharaj, Dr. Obajemihi, and Faruk’s work demonstrates how scientific innovation and environmental engineering can address multiple challenges at once — water scarcity, pollution, and agricultural productivity. By advancing cold plasma technology and exploring its real‑world applications, the RAU team is helping shape a future where farming is not only more efficient but also more environmentally responsible. Their research highlights the potential of PAW as a practical tool for modern agriculture and underscores the importance of continued investment in sustainable engineering solutions.
