Biochar:
A Carbon-Negative Technology to Combat Climate Change and Enhance Global Soil Resources
Feeding a Hot and Hungry Planet: The Challenge of Making More Food and Fewer Greenhouse Gases Debbie Reed Policy Director, International Biochar Initiative
Friday, May 1, 2009 biochar-international.org
Biochar Overview • What is Biochar? • Ancient Technology, Rediscovered • Impacts, Utilization of Biochar • Biochar and Climate Change
What is Biochar? • Biochar is a charcoal substance produced from the controlled, incomplete combustion of biomass in an oxygen-free or oxygen-limited environment. • As a soil amendment, biochar creates virtually permanent carbon sinks (MRT 1,000-2,000 years); dramatically improves soils; and has multiple environmental benefits. • Biochar is a carbon-negative technology, and can remove CO2 on gigaton scales, to combat climate change. It is one of the few carbonnegative technologies at our disposal.
What is Biochar? • During biochar production, up to 50% of the biomass feedstock C is retained in the crystalline biochar structure (Lehmann, 2007) • Bio-energy is a co-product (oil or syngas) – Thermal energy (cooking, heating) – Oil or gas for on-farm electricity generation – Oil or gas for refining, fuel production
• Biochar production systems are scalable, and have appropriate developed and developing country applications
What Makes Biochar Carbon-Negative? CO2 Cycle (simplified): • CO2 is captured by photosynthesis, and fixed into biomass • Biomass decays into CO2 BIOCHAR halts the decay process, and captures the CO2 in a virtually permanent carbon stock, preventing re-release to the atmosphere. • IT IS A CARBON-NEGATIVE PROCESS. • BURY IT!! As a soil amendment, biochar has beneficial agronomic and water quality impacts.
Terra Preta Soils: An Ancient Technology • Biochar is “newly rediscovered” • Concept: “Terra Preta de Indio” soils • Terra Preta soils of Amazon basin contain up to 70x more black carbon than surrounding soils, and high levels of nitrogen, phosphorus, potassium, and calcium
Terra Preta de Indio Soils Terra Preta de Indio Soil
Nearby Oxisol Soil
Photos: Julie Major, Cornell University
Impacts of Biochar Crop and Soil Impacts: • • • •
Enhances crop productivity Improves soil tilth, fertility, water retention Reduces soil erosion Reduces need for fertilizer inputs
Impacts of Biochar GHG Impacts: • Nitrous oxide emissions reduced 50-80% from cropland soils • Some evidence of methane supression • Stable, virtually permanent ٭soil carbon pools )M (٭ Water Quality Impacts: • Biochar strongly adsorbs phosphate • Reduces leaching of nitrogen and phosphorus
What makes Biochar work? • During formation, the porous, crystalline biochar structure adsorbs bio-oils, nitrogen, phosphorus, other nutrients from feedstock • Very high surface area • In soil, biochar is extremely recalcitrant to decomposition • Soil microorganisms and H2O inhabit micropores • Nutrient leaching and volatilization are inhibited, but nutrients are bioavailable to plants Source: Robert Brown, Iowa State University
Research in Past 5 Years Shows Biochar… • …is more stable than any other soil amendment (MRT 1,000-2,000 yrs) • …increases nutrient availability beyond a fertilizer effect • …is more efficient at enhancing soil quality than any other organic soil amendment
Biochar Utilization • Biochar in a developing country context: – Household-level biochar systems can combine cooking function with biochar production for crops (gardens, farms), biomass production for fuels – Enhance food & energy security, reduce land degradation and desertification
IBI & UNCCD: Biochar to help Avoid, Reverse Desertification?
Photos: International Development Research Center (www.idrc)
Biochar Utilization • Biochar in industrialized agriculture: – Utilization of waste biomass (e.g. peanut or rice hulls, corn stover, wheat straw, tree waste, animal manure) to produce biochar
Biochar Utilization • Biochar in industrialized agriculture: – Waste management to produce biochar – Biochar can reduce the need for fertilizer inputs, enhance crop productivity, soil quality – Biochar can improve water quality impacts of agriculture
Biochar and Climate Change • Soils store nearly 4X more organic C than atmospheric CO2 • Atmospheric CO2 cycles through biosphere every 14 years • Annual uptake of CO2 by plants is 8X greater than anthropogenic CO2 emissions • Diver&ng only a small propor&on of cycling C into biochar (e.g., 1%) would mi&gate almost 10% GHG emissions Source: Sabine, et al (2004)
The International Biochar Initiative • A consortium of research, commercial, and policy-oriented institutions and people devoted to sustainability of world’s soils, and climate change mitigation • Formed at 2006 World Congress on Soil Science • 1st international conference Spring, 2007 in Australia (www.iaiconference.org) • 2nd international conference Sept. 8-10, 2008 in Newcastle, UK (www.biochar-international.org)
The International Biochar Initiative
www.biochar-international.org