Onnu, a UK-based technology provider, has entered a strategic partnership with project developer ReGenEarth to launch a fully circular waste-to-energy facility at Hope Farm in Sedgefield, United Kingdom. This initiative integrates Onnu’s CarboFlow pyrolysisPyrolysis is a thermochemical process that converts waste biomass into bio-char, bio-oil, and pyro-gas. It offers significant advantages in waste valorization, turning low-value materials into economically valuable resources. Its versatility allows for tailored products based on operational conditions, presenting itself as a cost-effective and efficient More technology with ReGenEarth’s existing anaerobic digestion (AD) infrastructure at a working dairy farm supplying Arla. Financed as part of ReGenEarth’s £100 million Green Bond program, the development aims to transform the site into a multi-purpose hub capable of renewable energy generation, biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More production, and carbon removal.

The primary operational challenge addressed by this project is the efficient management of agricultural byproducts and the optimization of energy loops within AD facilities.  Traditionally, handling wet digestate from anaerobic digesters presents logistical and economic hurdles. Furthermore, standalone AD systems often miss opportunities for deeper carbon sequestration and require external energy inputs for processing residues, which can diminish the overall sustainability profile of the operation.

To resolve these inefficiencies, the Sedgefield site will deploy dual CarboFlow pyrolysis units integrated directly with the AD plant. This configuration establishes a closed-loop system: agricultural residue feeds the digester, and the resulting wet digestate is dried using thermal energy recovered from the pyrolysis process.  The dried digestate, along with locally sourced arboreal residues, is then pyrolyzed to create biochar. This method utilizes diverse feedstocks to ensure operational resilience and achieves energy autonomy by recycling heat to dry the digestate, removing reliance on external power for this specific function.

Once fully operational on the 3,500-acre farm, the facility is projected to deliver significant quantifiable results. The system is designed to produce 2,266 tonnes of biochar annually and generate 2.8 MW of recoverable thermal energy. From a climate perspective, the project anticipates removing 4,300 tonnes of CO₂e per year, with credits eligible under the Puro.earth framework.