Turning Grape Waste into Green Gold: The Green Circle’s Biochar Innovation

The Green Circle and Yealands Wine collaborate to convert grape waste into biochar, a carbon-rich substance. Demonstrated during Climate Action Week, the pilot process transforms wood-waste and vine stumps into moisture-retaining biochar, potentially revolutionizing agriculture. Scaling up poses challenges, but the initiative aims to offset emissions in Marlborough’s grape production chain.

March 2, 2024

1–2 minutes

Blenheim startup, The Green Circle, in collaboration with Yealands Wine, is pioneering an innovative method to convert grape waste into 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 – a substance composed of 80% pure carbon. Demonstrated during Climate Action Week Marlborough, the process involves using a machine to transform forestry wood-waste and grapevine stumps into biochar, a charcoal-like material. The biochar, which retains moisture and supports soil health, could be a game-changer for agriculture.

Steve Brennan and David Savidan, leaders at The Green Circle, explained that the pilot machine would be utilized to dry marc, the byproduct of winemaking, at Yealands this vintage. The challenge lies in scaling up the process to efficiently use available waste and make biochar cost-effective. Despite this, the company plans to have multiple machines capable of processing 15,000 to 20,000 tonnes by the next year.

The potential impact is substantial, considering Marlborough’s annual grape harvest of nearly 393,865 tonnes, with 20% being marc. Beyond vineyards, The Green Circle envisions converting vine trunks and prunings through 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. The biochar produced could be integrated into vineyards, offering a carbon-neutral solution.

While demand for high-carbon biochar is not yet prevalent in New Zealand, Yealands is eager for sustainable alternatives due to runoff concerns from composting marc. The Green Circle plans to charge clients for processing grape marc, offering discounted rates for purchasing biochar. Additionally, the company is exploring collaborations with forest and aquaculture industries to extend the application of its pyrolysis technology.

A significant endorsement for biochar comes from a joint study by Marlborough District Council, Massey University, and the Ministry for the Environment, emphasizing its environmental benefits. This initiative positions biochar as a promising avenue to offset emissions in the grape production and supply chain.