Key enablers for carbon dioxide removal through the application of biochar to agricultural soils: Evidence from three historical analogues

Abstract

Applying biochar to agricultural soils has the potential to sequester gigatons of carbon dioxide each year, while also improving agricultural yields and remediating soil pollutants. This, however, will require extremely fast growth of three subsystems: One to provide adequate material inputs (such as feed crops or agricultural byproducts); one to pyrolyze those inputs into biochar; and a third to distribute the product to farmers who spread it on soils. The growth of each of these subsystems faces unique social, political, and economic opportunities. We provide insights on these using three historical analogues: Fertilizer, ethanol fuel, and compost. These suggest several important findings for biochar: 1) Economic benefits for those who provide critical material inputs are important; 2) Generous investment in production facilities will be critical and should come from sources other than just carbon credits; 3) A distributed knowledge and quality control infrastructure will be necessary to support farmers using biochar; and 4) Biochar should be part of a wider transition to carbon-negative farming.