Charcoal Ain't Gonna Cool the Planet (Duh)!

Print Friendly, PDF & Email

Biochar supporters promote buried charcoal as a clean, natural solution to glonal warming, but scientific evidence is pretty much non-existent, and the danger it poses to forests is very real.

by Rachel Smolker

It’s downright amazing what people are willing to put their faith in when confronted with a crisis. With ever more dire impacts from a cooking planet, the “biochar worshippers” are doing their best to sell the idea that we can cure just about everything — from global warming to soil infertility, agrichemical runoff, even dirty toilets — by doing a little more cooking.

Related reading (PDF):
Biochar for Climate Change Mitigation: Fact or Fiction?

Just cook up some trees, agricultural “wastes and residues” — maybe a few hundred thousand acres of industrial tree monocultures (why not?) and then bury the resulting charcoal in soils to “sequester” it. This, they refer to as “a powerful tool to fight global warming.” (Footnote: If you think referring to them as “worshippers” is overstepping, see below.)

So convinced are they that charred plant matter is the answer to global warming, that the International Biochar Initiative, (IBI), a group consisting of a mix of business, academic and hybrid interests, has spent tons of time and money zealously lobbying to have biochar included in all manner of policies intended to address climate change: from the UN and other carbon trading venues to the proposed “Water Efficiency via Carbon Harvesting and Restoration Act” (WECHAR) bill introduced by Senator Harry Reid from Nevada, which would have us char trees and other “biomass” from National Parks.

The worshippers are now basking in success having managed to convince John Kerry et al to feature biochar prominently in the recently released senate climate bill, the “American Power Act.” So successful were they that biochar appears in three different places in the bill, under “rapid mitigation,” in the domestic offsets provisions, and under a title that directs EPA to explore its potential for “reducing black carbon.”

This is very disturbing. First of all, the biochar worshippers’ faith in biochar is largely based on extrapolation and wishful thinking. We know that indigenous peoples in the Amazon created remarkably fertile, carbon rich soils — called Terra Preta — between 500 and 2,500 years ago by adding a mix of kitchen waste, fish bones, river sediments and many other diverse residues as well as charcoal to their soils over very long periods of time. Nobody knows exactly how Terra Preta was created, nor whether it can be achieved quickly or in other soil types.

The biochar worshippers like to claim they are making something like Terra Preta when they pyrolize everything from wood to municipal solid waste, and that their biochar will similarly last for thousands of years. But there is little basis for comparison between modern biochar and ancient Terra Preta. As the UN Food and Agriculture Organisation states: “The knowledge systems and culture linked to the Terra Preta management are unique but have unfortunately been lost.”

For the past year or so, Biofuelwatch and others have been raising concerns about biochar — especially that big new demands for biomass are a threat to farms and forests already suffering from soil degradation and deforestation. We have repeatedly pointed out that there is no proof that biochar improves soil fertility (beyond an initial early effect due to nutrients in the ash residue).

Nor is there any proof that it performs as well as compost, let alone better! Nor is it by any means clear that the overall effects of biochar are good for the climate, especially if we account for the emissions from growing, harvesting collecting, transporting and pyrolyzing all that plant material.

There are no peer-reviewed comprehensive field studies of modern biochar lasting more than a year yet published! This is problematic given that in the real world, living soils are enormously variable, teeming with a huge variety of microbes and subjected to all kinds of climatic vagaries — droughts, wildfires, floods and more.

One (not peer-reviewed) field trial on a GM soya plantation in Quebec, used wood biochar made by Dynamotive. The soy yields were a bit higher in the first year compared to using nothing but lime, but then dropped off in the second. In spite of the persistent claim that biochar remains stable in soils for thousands of years, the researchers found no increase in soil carbon 2 years after the biochar was applied.

In another study in Central Amazonia, biochar was compared with chicken manure. Manure worked better.

There are also concerns that since toxins are concentrated in char, they could end up in soils and enter the food chain. Although the climate bill directs EPA to study biochar’s potential for reducing soot (small particles of black carbon which contribute to global warming), biochar itself breaks down over time into fine dust which can easily become airborne, like soot. These particles also cause lung disease when inhaled.

Pro-biochar organisations and companies, including WorldStove (whose Haiti project featured in two recent Huffington Post articles) are promoting biochar use amongst farmers in Haiti, Africa and elsewhere, and the IBI seeks to emphasize their image as “humanitarians,” featuring images of poor farmers hoeing charcoal into their fields. But small stoves projects are only a part of the picture.

From the get go, members of the IBI have advocated for very large scale biochar production as a “climate geoengineering” technology, with statements that biochar can sequester “gigatons” of carbon out of the atmosphere — or “reduce atmospheric CO2 concentrations by 100 parts per million,” or even “absorb all of the carbon emissions from fossil fuel burning that has occurred in the past 50 years.”

Such claims should cause us to wonder: how much biomass would it take, and where will it all come from? With an expanding population to feed and forests and ecosystems spiraling downward in decline, does it make sense to burn a lot of plant material, especially when there is so little evidence it will do any good?

Towards making their grand visions for biochar a reality, the IBI has recently partnered with the Carbon War Room, founded by airline owner and space-tourism entrepreneur Richard Branson. There, they are promoting “Operation Black Gold” which will “Apply Overwhelming Force” to ensure that biochar gets included into different carbon trading schemes and is granted prominence on the agendas of large NGOs.

They also seek to set up a biochar trade association with the goal of “removing” one billion tonnes of carbon from the atmosphere — an experiment that would require billion tonnes of wood be burned. They consider members of the UNFCCC and the scientific community who have raised concerns to be no more than “obstacles” to be overcome.

So perhaps it should not be too surprising that biochar features rather prominently in the Senate climate bill as a means of “enhancing soil sequestration” for “Achieving Rapid Mitigation.” The bill proposes up to 60 pyrolysis plants producing biochar which will require vast quantities of materials — trees, crops, residues, whatever is handy.

To understand how absurd this is, consider that the Terra Preta soils contain around 25 tons of carbon from biochar per hectare. Since wood is about 50% carbon, and at least 65% of that is normally lost during charring — one would have to burn about 143 tons of biomass per hectare to achieve a similar concentration.

The American Power Act further offers polluters the chance to avoid reducing their pollution, offsetting: it by paying for more biochar production. Offsets are a farce in the first place, and we can ill-afford to engage them at this point. The lack of certainty over the impacts of biochar highlights one of the most common criticisms: namely that real and measurable emissions from fossil fuel burning cannot be “offset” by questionable practices that may or may not work now or in the future.

Promoting the widespread use of biochar at this point is not unlike a drug company pushing a new compound without even testing it, because “it might work, or at least some people think so.”

Biochar advocates say they don’t want to see natural forests being cut down. They prefer to talk about using “wastes and residues, just as do the purveyors of bioenergy and biofuels. But in reality there are no mountains of wastes and residues lying about, and already forests from Indonesia to Argentina and Colombia are being destroyed ever faster — to the tune of escalating human rights abuses and hunger.

Forests are cut and replaced with industrial monocultures to supply the ever growing demand for wood chip and pulp.

And of course it is precisely that ever expanding market that lies behind Arborgen’s development of genetically engineered eucalyptus, just approved for field testing in the southeastern U.S. Biochar in the climate bill just added more fuel to the fires.

Rachel Smolker is codirector of Biofuelwatch, and an organizer with Climate SOS. She has a Ph.D. in behavioral ecology from the University of Michigan and worked as a field biologist before turning to activism.


The Terra Preta Prayer,
by biochar worshipper extraordinaire, Erich Knight

Our Carbon who art in heaven,
Hallowed be thy name
By kingdom come, thy will be done, IN the Earth to make it Heaven.
It will give us each day our daily bread and forgive us our atmospheric trespasses
As we forgive those who trespass against the Kyoto protocols
And lead us not into fossil fuel temptation, but deliver us from it’s evil
low as we walk through the valley of the shadow of Global Warming,
I will feel no evil, your Bio-fuels and fertile microbes will comfort me,
For thine is the fungal kingdom, and the microbe power, and the Sequestration Glory,
For ever and ever (well at least 2000 years) AMEN
Your Chartarian,


  • I’m sorry but your views of bio-char and the use of charcoal amendments to soils are overly simplistic and since they involve a healthy heaping of conspiracy theories, totally wrong.
    Compost is wonderful for making nice gardens and delicious vegetable but it is not a long term sink of C as it will decompose over time and release that CO2 back to the atmosphere.
    I suppose we could all just sit back and wait for people to stop consuming natural resources and for populations to stop growing and for fossil fuels to stop being burned and for the world to just restore itself on its own. In the meantime, people who have real training in nutrient cycling and soil ecology understand that pyrogenic C additions to soil have many complex interactions that can not be understood in isolation or in short time scales.
    Corporate agriculture is anathema to a sustainable future whereas permaculture practices are key to providing nutritious foods to the world’s people. If we allow corporations to absorb the entire black carbon market then it could also be a negative, but ad hominem attacks on research scientists are not a positive response.

  • See “Biochar produced as the byproduct of gasification of sugar cane bagasse the main product being synthesis gas used in an IC engine to generate electricity in small scale farming system”

    Rodríguez L, Salazar P and Preston T R 2009: Effect of biochar and biodigester effluent on growth of maize in acid soils. Livestock Research for Rural Development. Volume 21, Article #110.

  • The biochar cult is just a variation on “carbon capture and storage” – another techno-fix based more on wishful thinking than science.

    If we want to have carbon buried in the ground for thousands of years the best way is to leave alone the fossil carbon that’s already down there.