blog — drawing open

The Kuku Biochar Project – our first biochar burn!

On the 6th of April 2021 members of the Kei Uta Collective and Te Waituhi ā Nuku: Drawing Ecologies worked with Phil Stevens from Slow Farm for the first burn in our brand new flame cap biochar kiln designed and manufactured by Phil. The group convened at Kuku and was made up of Monique Jansen, Mark Harvey, Huhana Smith, Maria O’Toole and Lisa Munnelly. Plus kids, dogs, goats…

The burn took approximately 4 hours from start to finish. The process was slow and required constant gentle supervision as the kiln was continuously fed dry branches gathered from the old dead plum tree by the house (thanks plum tree - your wood has not been wasted and will be returned to the whenua!). Starting with fine twigs and moving to larger branches, the aim was to keep the fire burning at the correct temperature with an active flame cap across the top of the open kiln to stop oxygen getting to the burning wood underneath. Through this process, the volatile substances in the timber are burned off by the high temperature and the kiln burns cleanly creating no black or white smoke at all. Once the kiln was full and still burning, it was quenched with water, which cooled the charcoal within minutes. The process of the burn converts carbonous biomass into biochar; a stable, highly porous charcoal high in organic carbon. Phil declared the biochar burn a success and the charcoal excellent quality!

The Kuku Biochar Project is a three-part project lead by Monique Jansen to explore the potential of biochar for wetland restoration, as a soil amendment for regenerative agriculture and for carbon sequestration. Coming next in the Kuku Biochar Project:

An Artists and Designers Guide to Biochar – a user’s guide to biochar for artists and designers, which will give instructions for making and using biochar in the studio and at home, where it can be used for gardening, agricultural and carbon sequestration.

A Constructed Wetland for Kuku – this is a site specific project, which will test the efficacy of biochar to improve water quality. Sourcing all primary materials from Kuku, knitted socks/sacks will be made from sheep wool and filled with biochar. These will be placed in sedimentary basins or trenches at a point where run-off from farm land washes into a waterway. A citizen science project will test water quality over a year-long period to determine the extent to which biochar can effectively capture nitrogen run-off and reduce water pollution.

Artworks - Kuku biochar will be ground to a powder and used to experiment with drawing, casting and 3D printing. The subsequent objects will be exhibited and returned to the whenua at Kuku, to close the ecological loop. We really love the idea that we know the provenance of our charcoal, which highlights a problem with the art materials industry - most conventional art materials in Aotearoa are imported and have a large carbon footprint as a result.

Massive thanks to Phil for the fantastic learning, the generosity and korero solving the problems of the world! It was great to meet your whanau and be part of the Slow Farm kaupapa. And thanks to Huhana, Richard, Lynn and Tama for their manaakitanga, great company and delicious food!