A ‘missing link’ in the sustainability of controlled environment agriculture (CEA) has been filled, following the successful conclusion of a project to develop high-tech hydrogel-based substrates for hydroponic systems.
While peat-based substrates beat a retreat ahead of the peat ban, current alternatives – such as coir or stone wool – present awkward questions about carbon footprints and embedded energy.
“These substrates are at odds with the huge advances made in CEA technology in recent years,” notes Dr Aurélie Bovi, Innovation Sector Lead at CHAP – part of the Agri-Tech Centres. “They are unsustainable alternatives, presenting issues such as consistency of performance, supply security (coir) or disposal (stone wool), in contrast to the sector effort to reduce its carbon emissions.”
Dr Bovi co-ordinated CHAP’s involvement and key stakeholders’ engagement in the GelPonics project, that included the start-up AEH Innovative Hydrogel, Stockbridge Technology Centre, Grobotic Systems, and the Graphene Engineering and Innovation Centre at Manchester University.
The project focused on novel hydrogels, low-carbon polymers that can absorb as much as 600 times their own volume in water. Hydrogel formulations were optimised and tested in plant growth trials in CHAP’s Vertical Farming Development Centre. That led to the development of sheet prototypes and semi-commercial trials featuring common VF crops such as lettuce, rocket and microgreens.
“Our trials not only demonstrated the technology’s potential to offer a cost-effective, high-quality and consistent sustainable alternative to growers, but also its suitability to be combined with automation and use at scale,” Dr Bovi explains.
“Non-synthetic, biodegradable and compostable, the hydrogel has also proven to be effective in soil amendment.”
AEH’s GelPonics hydrogel will soon be commercially available.