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We must cut GHG levels not just emissions. Climate, nature and economies must recover together. Small scale biochar makes this possible.



      Executive Summary



      Why: Rational of the proposal

      How: Feasibilty of proposal

      Proposed Biochar economy actions

      Vision of the future under this proposal


Executive Summary

This proposal in MIT's Climate CoLab plans to maximise the potential benefits - to climate security, soil and ecosystem regeneration, economic recovery and co-operative lifestyles - of biochar.

"Biowhat??" The flame on burning wood is from the woodgas given off as the wood heats up. Most of the energy content of wood (or any dry biomass) comes from its woodgases. This woodgas can be used for heating and cooking with the left-over charcoal being kept as biochar and put it in soils.  Then it stores carbon and enables more biomass to grow (more food, more forests, more ecosystems).

Sustainable biochar is a game-changing climate solution. It uniquely provides renewable energy, energy and food resilience, carbon mitigation, adaptation and sequestration. It also offers civilisation an "AHA" moment when we suddenly embrace the full scope of the challenge and the opportunities. Forget incremental change - this is whole system change where the climate, ecosystems and economies all recover together. 

Biochar makes it possible to discuss and plan not only lower emissions (the convenient target) but also lower atmospheric CO2 concentrations (the necessary target - see references). Biochar regenerates soils making it possible for nature, forests and agriculture to expand without artificial fertilisers. This expansion can provide exponentially increasing biomass for more biochar. Biochar-based local economies would support small-scale biochar worldwide and avoid the risks of unsustainability from large-scale non-local biochar. 

Local economies using biochar to back new money supply can create the jobs and funds needed for biochar and related local sustainability activities. Local currencies backed by small-scale biochar would work together with national and international currencies and enable the fastest possible solutions to accumulated climate, ecosystem and economic problems. It is also necessary to 'fix the system' that drives these problems; please see the allied proposal for how to get a global 'circular economy'.


James Greyson, lead author. Blindspotter on the Climate CoLab. Blindspotting and Climate_Rescue on twitter. Head of BlindSpot Think Tank. Head of MicroChar, working to enable worldwide small scale biochar to reverse the process of climate change. Designing innovative clean cookstoves and policies to make them available everywhere.

Dr Andrea Berardi andrea-berardi. Lecturer in environmental information systems, Chair of Open University Development and Environment Society. 

Erich J. Knight erich. Biochar consultant. Chairman; Markets and Business Committee, 2010 US Biochar Conference.

More supporters, comments, team members and input are very welcome :-) 


Biochar is charcoal that's mixed into soil rather than burnt. Making biochar is easily done using simple equipment (that can even be built by kids from scrap materials) and easily accessible surplus garden or agricultural residues. By-products of biochar can include fuel gases and oils for heating and making electricity. 

Biochar is the most viable and least fanciful of all 'geo-engineering' and Carbon Capture and Storage technologies. Although it needs to be done sustainably (see actions 2 and 3 of the feasibility section) biochar offers a way to undo the globalised error of high fossil fuel dependence causing fast accumulations of waste products in the atmosphere and oceans. 

Biochar can be quickly and easily scaled up to create 'biochar economies' that rapidly cut fossil fuel dependence, remove accumulated wastes from the atmosphere, regenerate soils, expand ecosystems and boost the recovery of communities and their finances. 

Left: nutrient-poor soil; right: fertile terra preta (soil with added biochar). (Image: Wikipedia)

Biochar economies are significant also for their transformative potential for civilisation's collective thinking. Without this AHA! moment society is likely to end up where it is headed, with alternative movements remaining marginal and the opportunity for a sustainable reality fading away.  

Biochar economies would support a transformative global AHA! moment...

AHA 1: We must cut GHG concentrations not just emissions.The existing physical impacts of climate change are already intolerable (See References below) so existing GHG concentrations are already too high. This calls for an entirely new scale of ambition where humanity's future is to make net-positive impacts not just slower or steadier destruction. 

AHA 2: Joined up thinking. Biochar invites the systems thinking we need to make sustainability actually happen. Cookers can create charcoal rather than burn it. Cookers using twigs incentivise tree planting rather than logging. Biochar enables soil and forest regeneration so mutiple problems can be solved at once. This overcomes the conventional idea that narrow change is easier than systemic change. 

AHA 3: Sharing. Biochar inspires sharing and invites hope in a shared future. Scaling up biochar requires sharing knowledge, technologies, finances, access to land, food growing, crops, biomass, communal spaces and meals. My regular carbon-negative coffee mornings have been an enjoyable local example.  

AHA 4: The whole idea of waste disposal can be discarded. Large-scale biochar makes waste incineration obsolete, since communities would wish to separately collect non-recyclable plant-based wastes (messy cardboard, paper, wood, dried plant wastes, sticks from hedge-cutting, etc) as feedstock for local energy supply and biochar. Green plant wastes and food wastes are unsuitable for making biochar and would be composted then mixed with biochar before adding to soils. Everything else would be 'precycled' (see allied proposal in the CoLab).

AHA 5: Biochar makes energy tangible, which shrinks energy demand. Renewable energy, and in particular biochar that requires a bit of effort to tend the crop-fuel-biochar-crop ecocycle, would induce society's high energy dependence to plummet. It's easier to avoid needing more energy than to produce more with renewables. High energy dependence is a product of centralised non-renewable energy supply. 

Why: Rationale for the proposal

Biochar is the only ready-to-use climate solution that unites mitigation (displacing fossil fuels, cutting energy dependence and reviving soils/ecosystems), adaptation (protecting against energy supply interruptions, operating in post-disaster situations, coping with depleted soils) and geoengineering (shifting carbon from biological cycles to geological storage - as a resource in soils). 

Biochar has an immediate potential for mitigation, adaptation and geoengineering that is internationally recognised as highly significant (See References below). Yet existing studies have yet to explore the full potential. What about domestic biochar-producing cookers in both developed and developing nations? How about combining biochar with rapid reduction of synthetic fertilisers, rapidly expanding ecosystems and low-tillage/perennial crop food production? How fast could biochar be taken up when suitable economic incentives become available? . The full potential is far greater than researchers have considered. 

Biochar is also valuable as a powerful leverage point for mental models and cultural habits that would enable a society to solve its problems rather than just keep making them worse. The opportunities presented by biochar lead people to think out of the box of conventions such as trying (in vain) to solve problems separately and a bit at a time. See AHAs above. 

How: Feasibility of proposal

Case study. As a case study of the feasibility of biochar we consider the destruction of forests in developing countries by communities dependent upon charcoal for cooking. The wood that is used for charcoal-making is typically not seasoned so the high moisture levels mean that the energy potential of the charcoal is also very low, containing only around 5% of the calorific value of seasoned wood. 95% of the available energy of the wood is wasted - actually much worse than wasted since the woodgases emitted during charcoal-making are released unburnt as GHGs (with similar global warming potential to methane - around 30X CO2).

Dramatic reversals of problems.  Biochar cookers use twigs from trees as fuel rather than wood from cut trees. Thus the incentive is to plant trees rather than cut them down. This can include coppices and orchards, to produce both fuel and food. The cookers make charcoal rather than burning charcoal. This turns a cost (buying charcoal) into a valuable product (charcoal to store, sell or add to soil). The cookers work by burning the woodgases produced as twigs become charcoal. This turns a pollutant into a source of heat for cooking, with around 80% of the calorific value of the wood used (compared to previously 5%). With a flue or chimney the cookers can be used indoors. Without a flue they can be used outdoors and are ideal for communal cooking, sharing meals and celebrations. The biochar produced can earn carbon credits and also be applied in compost to depleted soils, building food security, drought resistance and expansion of ecosystems. The biochar acts as a reservoir for air, beneficial micro-organisms and nutrients. If fertilisers are being used, the amounts (and their costs) can be reduced significantly. The cookers can be made from scrap materials, with simple tools (no power tools needed) and communities can make their own, which generates income rather than adding indebtedness or aid-dependence. 

Calculating the potential of biochar. Existing calculations of the global potential for biochar underestimate the opportunity. Biomass is currently wasted (rotted or burnt) on an epic scale and only part of this waste has been considered in existing studies. In my neighbourhood for example approximately 0% of the surplus twigs from roadside trees are used for biochar (I'm the only person using them!). Talk of limits to sustainable biomass for biochar is misleading since biochar provides the means for biomass (food and forests) to expand, by reviving soils that are significantly depleted in both developed and developing countries. Carbon credits and the proposed biochar-based local currencies would enable the global loss of nature to be reversed, so the net effect of biochar should be to expand biomass lows not to appropriate them. AHA 5 above suggests that typical calculations for the contribution of biochar to global energy needs are underestimates. Biochar production potential is greater than estimated (and almost entirely untapped). And when energy comes from biochar people suddenly find they don't need so much. For example homes heated by biochar boilers would quickly be super-insulated to save effort. Fields with biochar enriched soils would need less mechanical effort to plough so tractors would need less diesel. Incinerators closed to harness biomass for biochar would stimulate sudden high levels of composting, recycling and reuse to deal with the residual wastes - all activities with massive energy savings. Such examples can be found throughout the economy. 

Considering the above, quantifications of potential would require a major research project and cannot be given here. However I would say that previous estimates of maximum potential (such as the recent Nature study, ref. 9 below) should instead be considered as a minimum. Hence the global potential for biochar is at least 1.8 Pg CO2 -C equivalent (CO 2 -Ce ) per year or 12 % of current anthropogenic CO 2 -C e emissions; 1 Pg = 1 Gt. 

Modelling for this proposal. The models used in the Climate CoLab are not designed to consider proposals with low target CO2 concentrations nor proposals where the economics is adjusted to accommodate necessary changes. Hence the models do not indicate that this proposal is unfeasible. In contrast, the conclusion from the models should be that the models are not currently feasible for assessing this kind of proposal and further modelling work is needed to provide models that work in the territory where humanity now finds itself. This proposal is also allied with the Fix the system proposal so modeling should consider both together.

Proposed Biochar economy actions

To rapidly achieve the global potential for biochar I propose 5 actions:

Action 1: Open-source super-simple high-efficiency easily-built biochar-making cookers! Through this proposal I hope to find funding and implementation partners to support the open-sourcing of my 'simplest possible' domestic biochar cooker design for immediate use worldwide. The design includes many innovations that advance the performance beyond other DIY cookers. Please contact me (blindspotter) by sending a message from my profile page on the CoLab. See also comment #5 by rasmus with many more technical possibilities with biochar.

Action 2: Arrange public, private and carbon financing to support forms of biochar that are sustainable. 

  • Biomass feedstock from surplus sources, not food crops or fuel crops. 
  • Woodgas that is entirely burnt not lost as pollutants to air. 
  • Heat from burning woodgas that is used productively not just flared off.
  • Scales of use that minimise transport, from households to bio-regions.
  • Creating local markets for biochar to connect small producers with large users. 
  • Ensuring biochar is sieved, preloaded (with for example compost) and mixed into topsoils.  
  • Supporting knowledge and practice of growing trees/food with biochar. 
  • Supporting innovations such as biochar space and water heating. 
  • Supporting an end to both dumping and burning of biomass wastes.
  • Supporting a rapid global expansion of nature, topsoils, forests and ecosystems (see how).
  • Revenues that prioritise non-profit, shared and communal open-access.
  • Carbon markets and subsidies that track ecosystem and community benefits as well as carbon flows.
  • Politicians who are attracted to small and simple as well as big, lucrative and high-tech.
  • 'Clean energy' and 'clean cookstove' initiatives that aim for carbon-negative not just less smoke or more efficient burning.
  • Research that considers biochar within the context of a whole economy rapid transition to sustainability.


Action 3: Phase out public, private and carbon financing for forms of biochar that are unsustainable or wasteful.

  • Biomass feedstock that displaces food production. 
  • Biomass planting that replaces existing diverse productive ecosystems (including non-forest ecosystems).
  • Monoculture planting. 
  • Biomass transport further than necessary to find energy users. 
  • Biomass co-opted for private profit and inaccessible to local communities. 
  • Activity on foreign-owned land in countries with food shortage. 
  • Biochar that is burnt, not sieved/crushed, not distributed in soil, not preloaded with nutrients (compost or urine) or not used to expand cultivation or ecosystems (or other productive use such as water filtering or insulation). 
  • Biochar technology that is not open-sourced for global availability and rapid technical advance. 
  • Woodgas that is needlessly flared or lost as climate-hostile pollutants to air (for example in old-fashioned charcoal-making). 
  • 'Clean cookstoves' that replace biomass with fossil fuels or non-renewable electricity.
  • 'Clean cookstoves' that are less smokey than open fires but do not make biochar. 


Action 4: Allow local currencies to support local biochar production. Local and national economies are in decline worldwide due largely to the basic error of overlooking how money needs to be based on a tangible source of value. Allowing most money to be based on the creation of additional debt to banks is unfortunately destructive of value of all kinds. My peer-reviewed research published in the NATO Science Programme shows how correcting this error is a huge opportunity to build security locally and globally. The popular movement Positive Money is a recent example of how politicians and the media are finding that austerity and the debt crisis are optional and that money supply is not as complex as people imagine. 

In any future successful economy, money supply will come from a publicly accountable body such as a fully government-owned central bank. That would largely take care of national debt crises. However governments have shown with 'quantitative easing' that their instinct is to deliver new money to financial institutions (mimicking bank-created money) rather than providing money where it's needed throughout the economy. Action 4 would provide new money locally wherever it is needed to create jobs, regenerate nature, build food security and end austerity mindsets.

Action 4 invites governments to allow local communities to establish publicly-accountable transparent non-profit bodies to create local currencies for local regeneration. The new local money would be created simply by being spent into the local economy to pay for activities that accelerate sustainable biochar production and use, for example on individuals and businesses that make and distribute biochar equipment or use biochar to expand and manage forests that provide renewable fuel for more biochar. Open-source, non-profit and community-based enterprises would be the core recipients. Once in the local economy, the new money would continue to circulate locally, supporting expanding economic activity of all kinds that would otherwise not happen. 

Transactions in local money would be included in national GDP accounts, allowing biochar to trigger local, national and international recovery of employment, economic activity, food production, ecosystem expansion, energy security and climate security. Using biochar as a kind of local 'gold standard' for local currency supply would improve the economics of biochar, making it happen faster. Many other activities could be used as the basis for local money supply however biochar is particularly well suited since it is tangible, measurable and compatible with all other sustainable activities. The Rio+20 conference is an ideal venue to highlight this opportunity for immediate use worldwide.

Action5: Disaster relief and refugee camps are awful for those affected but also an opportunity to help people recover social, ecological and financial capital by providing biomass and biochar cookers instead of fossil fuels that worsen the problems that cause many disasters. The cooking is ideally suited for shared use, bringing people together at a time when they feel separated. The biochar byproduct from cooking can be mixed with site-produced compost or urine and added to soils, then used immediately for growing food and planting trees. Biochar can even be used as a simple weight-based camp currency and used to support gardening efforts, exchange skills and bring in extra real money from carbon credits. 

For more information on biochar please see: International Biochar Initiative,

Biochar kilns,

This proposal  works well together with all other proposals on the CoLab, in particular: Fix the system - get a global 'circular economy'

Vision of the future under this proposal

 'The biochar economy' sketch from Open Source Ecology, sourced by rasmus (see comment #5). 


See also additional references in comment #2 by Erich. 

1. The Costs of Delay. ClimateWorks Foundation. 2011.

2. Arctic sea ice is thinning, on average, four times faster than the models say, and it’s drifting twice as quickly. Journal of Geophysical Research – Oceans. Pierre Rampal, MIT  Department of Earth, Atmosphere, and Planetary Sciences (EAPS); Jérôme Weiss and Clotilde Dubois of France’s Centre National de la Recherche Scientifique/Université Joseph Fourier and Centre National de Recherches Météorologiques, respectively, and Jean-Michel Campin, a research scientist in EAPS.
3. Climate Refugees. This book shows us damage wrought to homes and livelihoods by rapid warming near the Arctic; rising sea levels that threaten the island nations of Tuvulu, the Maldives, and Halligen; farmers displaced by the desert's advance in Chad and China; floods that wash away life in Bangladesh; and Hurricane Katrina evacuees in shelters far away from their New Orleans neighborhoods. Added to the devastating environmental effect of climate change is the immeasurable and irretrievable loss of ethnic and cultural diversity that occurs when vulnerable local cultures disperse. It is this often forgotten and tragic consequence of global warming that Collectif Argos painstakingly documents. MIT Press 2010.

4. Biochar was pointed out in the IPCC Fourth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC) as a key technology for reaching low carbon dioxide atmospheric concentration targetsFischer, B.S., N. Nakicenovic, K. Alfsen, J. Corfee Morlot, F. de la Chesnaye, J.-Ch. Hourcade, K. Jiang, M. Kainuma, E. La Rovere, A. Matysek, A. Rana, K. Riahi, R. Richels, S. Rose, D. van Vuuren, R. Warren, (2007)“Issues related to mitigation in the long term context”, In Climate Change 2007: Mitigation. Contribution of Working Group III to the Fourth Assessment Report of the Inter-governmental Panel on Climate Change [B. Metz, O.R. Davidson, P.R. Bosch, R. Dave, L.A. Meyer (eds)], Cambridge University Press, Cambridge.

5. The negative emissions that can be produced by biochar has been estimated by the Royal Society to be equivalent to a 50 to 150 ppm decrease in global atmospheric carbon dioxide concentrations"Geoengineering the climate: science, governance and uncertainty"The Royal Society. 2009.

6. According to the International Energy Agency, the BLUE map climate change mitigation scenario calls for more than 2 gigatonnes of negative CO2 emissions per year with biochar in 2050. "IEA Technology Roadmap Carbon Capture and Storage 2009"OECD/IEA. 2009.

7. Lehmann - Bioenergy in the Blacksupra note 3 at 384. (“In greenhouse experiments, NOx emissions were reduced by 80% and methane emissions were completely suppressed with biochar additions of 20 g kg-1 (2%) to a forage grass stand.

8. The Biochar Solution: Carbon Farming and Climate Change, by Albert Bates, New Society Publishers, October 2010. Combining practical techniques for the production and use of biochar with an overview of the development and future of carbon farming, The Biochar Solution describes how a new agricultural revolution can reduce net greenhouse gas emissions to below zero while increasing world food reserves and creating energy from biomass wastes.

9. Sustainable Biochar to Mitigate Global Climate Change