March 2015 Update: ACR Methodology for Emissions Reductions from Biochar Projects Listed As Inactive

In late March, the American Carbon Registry (ACR) listed the Methodology for Emissions Reductions from Biochar Projects as inactive, essentially eliminating prospects for its approval as currently drafted. This action was taken after the anonymous peer review panel assembled by ACR reached the conclusion that there was insufficient scientific evidence to support the Test Method for Estimating Biochar Carbon Stability (BC+100)—a core component of the overall methodology. IBI believe this outcome reflects the relative novelty of biochar science. Whereas biochar researchers around the globe largely agree on methods to estimate biochar carbon persistence utilized in the ACR methodology i.e., BC+100, the larger scientific community remains unfamiliar with recent advances in the field. Future efforts to revive the methodology in the ACR process—or other carbon offset registries—should focus on bolstering the evidence for BC+100, or developing novel methods to accurately estimate biochar carbon persistence under field conditions.

Biochar and Carbon Markets

In order to facilitate broad action on climate change, carbon markets have been developed which utilize greenhouse gas accounting and trading mechanisms to enable entities—whether governments, companies or other institutions—to mitigate, or offset, the GHG emissions associated with their activities. Quantification of the persistent carbon component of biochar can facilitate the participation of biochar projects in carbon markets, providing an additional revenue stream to projects delivering greenhouse gas emissions reductions through soil carbon sequestration.

For additional information on the climate benefits of biochar please visit

Methodology for Emissions Reductions from Biochar Projects

IBI along with partners The Climate Trust and The Prasino Group, developed and submitted a biochar carbon offset methodology for approval by the American Carbon Registry (ACR)—a leading voluntary carbon offset registry. The Methodology for Emissions Reductions from Biochar Projects—while listed as inactive by ACR in March 2015 essentially eliminating prospects for its approval as drafted—serves as an important template for future efforts to develop and garner approval of a biochar carbon offset methodology.

The Methodology quantifies the stable carbon component of biochar as well as the avoided emissions from feedstock that would otherwise undergo combustion or decomposition. Critical to the methodology is identification of a cost-effective, scientifically valid test to measure the stable carbon component of biochar when applied to soils. IBI led an effort to identify a test methodology to assess and quantify the stable carbon component of biochar—the Biochar Carbon Stability Test Method (available for download below). The objective of this Test is to measure the recalcitrant, stable component of carbon in biochar that will exhibit at least a 100-year residence time in soil (100 years being the pro forma definition of permanence in the Kyoto Protocol and applied to most other carbon offset programs, including ACR).

The latest draft of the Methodology is available for download here.

The Biochar Carbon Stability Test Method

To develop the Biochar Carbon Stability Test Method, IBI convened a group of world-class experts (the Expert Panel) in different fields relevant to biochar persistence and representing the research and commercial sectors. The goal was to identify a simple yet reliable and verifiable measure for biochar stability. Important requisites were defined for the test, including cost, repeatability, and availability. The Biochar Carbon Stability Test Method agreed upon by the Expert Panel uses the ratio of hydrogen to organic carbon (H/Corg)—as measured using standard analytical techniques—to estimate the fraction of biochar carbon that will persist in soil for 100 years.

The Test Method is available for download; please click here.

IBI wishes to thank the members of the Expert Panel, who voluntarily agreed to devote their time to this collective effort, for which we express our gratitude in the name of the global biochar community. The members of the Expert Panel include:

  • David Andersson, EcoEra, Sweden
  • Alice Budai, Norwegian Institute for Agricultural and Environmental Research – Bioforsk, Norway
  • Marta Camps, Institute of Natural Resources, Massey University, New Zealand
  • Annette Cowie, Rural Climate Solutions, University of New England, NSW Department of Primary Industries, Australia
  • Bruno Glaser, Soil Physics Group, University of Bayreuth, Germany
  • Stephen Joseph, School of Materials Science and Engineering, University of New South Wales, Australia
  • Johannes Lehmann, Department of Crop and Soil Sciences, Cornell University, United States
  • Caroline Masiello, Department of Earth Science, Rice University, United States
  • Paul Munroe, School of Materials Science and Engineering, University of New South Wales, Australia
  • Frank Shields, Control Laboratories, Inc., United States
  • Bhupinderpal Singh, NSW Department of Primary Industries, Australia
  • Saran Sohi, UK Biochar Research Centre, United Kingdom
  • Beau Webber, School of Physical Sciences, University of Kent, United Kingdom
  • Morgan Williams, Biochar Solutions, United States
  • Andrew Zimmerman, Dept. of Geological Science, University of Florida, United States