THE GREAT BIOCHAR DEBATE
[NOTE: I have been updating this post as comments arrive from many notable voices. They are appended to the Monbiot article.]
There's great biochar debate going on in at the guardian.co.uk with heayweights George Monbiot, Chris Goodall and James Lovelock pulling no punches. It's really worth considering. please ...
Woodchips with everything. It's the Atkins plan of the low-carbon world
by George Monbiot
The latest miracle mass fuel cure, biochar, does not stand up; yet many who should know better have been suckered into it
Whenever you hear the word miracle, you know there's trouble just around the corner. But no matter many times they lead to disappointment or disaster, the newspapers never tire of promoting miracle cures, miracle crops, miracle fuels and miracle financial instruments. We have a limitless ability to disregard the laws of economics, biology and thermodynamics when we encounter a simple solution to complex problems. So welcome, ladies and gentlemen, to the new miracle. It's a low-carbon regime for the planet that makes the Atkins diet look healthy: woodchips with everything.
Biomass is suddenly the universal answer to our climate and energy problems. Its advocates claim that it will become the primary source of the world's heating fuel, electricity, road transport fuel (cellulosic ethanol) and aviation fuel (biokerosene). Few people stop to wonder how the planet can accommodate these demands and still produce food and preserve wild places. Now an even crazier use of woodchips is being promoted everywhere (including in the Guardian). The great green miracle works like this: we turn the planet's surface into charcoal.
Sorry, not charcoal. We don't call it that any more. Now we say biochar. The idea is that wood and crop wastes are cooked to release the volatile components (which can be used as fuel), then the residue - the charcoal - is buried in the soil. According to the magical thinkers who promote it, the new miracle stops climate breakdown, replaces gas and petroleum, improves the fertility of the soil, reduces deforestation, cuts labour, creates employment, prevents respiratory disease and ensures that when you drop your toast it always lands butter side up. (I invented the last one, but give them time).
They point out that the indigenous people of the Amazon created terras pretas (black soils) by burying charcoal over hundreds of years. These are more fertile than the surrounding soils, and the carbon has stayed where they put it. All we need to do is to roll this out worldwide and the world's problems - except, for the time being, the toast conundrum - are solved. It takes carbon out of circulation, reducing atmospheric concentrations. It raises crop yields. If some of the carbon is produced in efficient cooking stoves, it reduces the smoke in people's homes and means they have to gather less fuel, curtailing deforestation.
This miracle solution has suckered people who ought to know better, including James Lovelock, Jim Hansen, the author Chris Goodall and the climate campaigner Tim Flannery. At the UN climate talks beginning in Bonn on Sunday, several governments will demand that biochar is made eligible for carbon credits, providing the financial stimulus required to turn this into a global industry. Their proposal boils down to this: we must destroy the biosphere in order to save it.
In his otherwise excellent book, Ten Technologies to Save the Planet, Goodall abandons his usual scepticism and proposes we turn 200m hectares of "forests, savannah and croplands" into biochar plantations. Thus we would increase carbon uptake by grubbing up "wooded areas containing slow-growing trees" (that is, natural forest) and planting "faster growing species". This is environmentalism?
But that's just the start of it. Carbonscape, a company that hopes to be among the first to commercialise the technique, talks of planting 930m hectares. The energy lecturer Peter Read proposes new biomass plantations of trees and sugar covering 1.4bn hectares.
The arable area of the UK is 5.7m hectares, or one 245th of Read's figure. China has 104m hectares of cropland. The US has 174m. The global total is 1.36bn. Were we to follow Read's plan, we would either have to replace all the world's crops with biomass plantations, causing instant global famine, or double the cropped area, trashing most of the remaining natural habitats. Read was one of the promoters of first-generation liquid biofuels, which played a major role in the rise in the price of food last year, throwing millions into malnutrition. Have these people learned nothing?
Of course they claim everything can be reconciled. Peter Read says the new plantations can be created across "land on which the occupants are not engaged in economic activity". This means land used by subsistence farmers, pastoralists, hunters and gatherers and anyone else who isn't producing commodities for the mass market: poorly defended people whose rights and title can be disregarded. Both Read and Carbonscape speak of these places as "degraded lands". We used to call them unimproved, or marginal. Degraded land is the new code for natural habitat someone wants to destroy.
Goodall is even more naive. He believes we can maintain the profusion of animals and plants in the rainforests he hopes to gut by planting a mixture of fast-growing species, rather than a monoculture. As the Amazon ecologist Philip Fearnside has shown, a mixture does "not substantially change the impact of very large-scale plantations from the standpoint of biodiversity".
In their book Pulping the South, Ricardo Carrere and Larry Lohmann show what has happened in the 100m hectares of industrial plantations established around the world so far. Aside from destroying biodiversity, tree plantations have dried up river catchments, caused soil erosion when the land is ploughed for planting (meaning loss of soil carbon), exhausted nutrients and required so many pesticides that the run-off has poisoned marine fisheries.
In Brazil and South Africa, tens of thousands of people have been thrown off their land, often by violent means, to create plantations. In Thailand the military government that came to power in 1991 sought to expel five million people. Forty thousand families were dispossessed before the junta was overthrown. In many cases plantations cause a net loss of employment. Working conditions are brutal, often involving debt peonage and repeated exposure to pesticides.
As Almuth Ernsting and Rachel Smolker of Biofuelwatch point out, many of the claims made for biochar don't stand up. In some cases charcoal in the soil improves plant growth, in others it suppresses it. Just burying carbon bears little relation to the farming techniques that created terras pretas. Nor is there any guarantee that most of the buried carbon will stay in the soil. In some cases charcoal stimulates bacterial growth, causing carbon emissions from soils to rise. As for reducing deforestation, a stove that burns only part of the fuel is likely to increase, not decrease, demand for wood. There are plenty of other ways of eliminating household smoke which don't involve turning the world's forests to cinders.
None of this is to suggest that the idea has no virtues, simply that they are outweighed by hazards, which the promoters have overlooked or obscured. Nor does this mean that charcoal can't be made on a small scale, from material that would otherwise go to waste. But the idea that biochar is a universal solution that can be safely deployed on a vast scale is as misguided as Mao Zedong's Great Leap Backwards. We clutch at straws (and other biomass) in our desperation to believe there is an easy way out.
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Response from Chris Goodall:
Biochar: Much is unknown but this is no reason to rule it out
Biochar - where wood and crop wastes are cooked to release the volatile components buried in the soil - is a cheap and highly beneficial way of disrupting the global carbon cycle
George Monbiot is right to tell biochar enthusiasts to calm down. Some of us have been guilty of febrile proselytising for this most unlikely scheme for geo-engineering. It is often thus: it is only after a period of reflection and assessment that some of the disadvantages of a new weapon against climate change become apparent.
Nevertheless in his eagerness to get us to tone down our enthusiasm he goes too far. Biochar is a useful and important way to help reduce atmospheric concentrations of CO2.
First of all, let's ask why small knots of dedicated people have been focusing on biochar for the past five or 10 years. Biochar looks as if it is a cheap and highly beneficial way of disrupting the global carbon cycle.
As plants grow, they naturally absorb carbon dioxide, only to give it back as they die and then rot away. Huge volumes of carbon are continuously moving between the soil, plants and the atmosphere, dwarfing the emissions from the burning of fossil fuels. If instead of letting plant matter rot, it is turned into charcoal which is almost pure carbon and stable for many centuries, we are reducing atmospheric concentrations of CO2.
No one disputes the basic science, even George. If we can get this to work on a large scale, we can make a significant difference to greenhouse gas levels. We will have to take the organic outputs of large areas of land in order to achieve this and Monbiot is right to express horrified disbelief at some of the figures that we have suggested.
Here we depart from the path of agreement. Monbiot mentions but then ignores the other benefits of biochar. These are at least as important as direct climate change mitigation. First, soil dosed with charcoal can substantially improve agricultural productivity. Food crops grow better. Trees planted in biochar often have better root systems. Crop yields are improved. This means that we can provide food supplies for more people from a smaller area of land. Growing bigger plants and trees, which are largely made from carbon, hydrogen and oxygen has a secondary effect of holding back CO2 that would otherwise be in the air. It is another form of useful carbon sequestration, albeit a once-only gain, adding to the primary effect of storing charcoal in the soil.
The second effect of biochar is to reduce the emission of other greenhouse gases, such as nitrous oxide and methane, from the soil. Thirdly, conventional fertilisers added to biochar appear to be much more effective and less likely to be washed away. Biochar-dosed soil therefore maintains its fertility better.
No one argues that biochar's effects are well understood. Scientific investigation is only just beginning. Next month sees the publication of Biochar for Environmental Management, a book edited by Johannes Lehmann and Stephen Joseph, two of the world's pre-eminent scientific advocates of biochar. This 400-page book is not the work of gullible fools, it is a resolutely serious attempt to tell the world of the many uncertainties surrounding how best to make and apply biochar.
Its chapters on climate change mitigation are not an attempt to minimise the problems but rather to offer realistic and practical ways of utilising biochar's beneficial properties for the good of the planet and its poorer people. Yes, we don't yet understand fully why biochar works but this is not an argument to ignore it or rule it out. I challenge George to read the science in this book and then tell us whether he is quite so sceptical as he is today.
• Chris Goodall is the author of Ten Technologies to Save the Planet
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Response from James Lovelock
Biochar: let the Earth remove C02 for us
What we have to do is turn a portion of all the waste of agriculture into charcoal and bury it
I usually agree with George Monbiot and love the way he says it but this time – with his assertion that the latest miracle mass fuel cure, biochar, does not stand up – he has got it only half right.
Yes, it is silly to rename charcoal as biochar and yes, it would be wrong to plant anything specifically to make charcoal. So I agree, George, it would be wrong to have plantations in the tropics just to make charcoal.
I said in my recent book that perhaps the only tool we had to bring carbon dioxide back to pre-industrial levels was to let the biosphere pump it from the air for us. It currently removes 550bn tons a year, about 18 times more than we emit, but 99.9% of the carbon captured this way goes back to the air as CO2 when things are eat eaten.
What we have to do is turn a portion of all the waste of agriculture into charcoal and bury it. Consider grain like wheat or rice; most of the plant mass is in the stems, stalks and roots and we only eat the seeds. So instead of just ploughing in the stalks or turning them into cardboard, make it into charcoal and bury it or sink it in the ocean. We don't need plantations or crops planted for biochar, what we need is a charcoal maker on every farm so the farmer can turn his waste into carbon. Charcoal making might even work instead of landfill for waste paper and plastic.
Incidentally, in making charcoal this way, there is a by-product of biofuel that the farmer can sell. If we are to make this idea work it is vital that it pays for itself and requires no subsidy. Subsidies almost always breed scams and this is true of most forms of renewable energy now proposed and used. No one would invest in plantations to make charcoal without a subsidy, but if we can show the farmers they can turn their waste to profit they will do it freely and help us and Gaia too.
There is no chance that carbon capture and storage from industry or power stations will make a dent in CO2 accumulation, even if we had the will and money to do it. But we have to grow food, so why not help Gaia do the job of CO2 removal for us?
• James Lovelock is an independent scientist, author, researcher, environmentalist. He is known for proposing the Gaia hypothesis.
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We never said biochar is a miracle cure
by Pushker Kharecha and Jim Hansen
George Monbiot's implication that we believe biochar is a miracle solution to CO2 reduction is grossly misunderstood.
It is unfortunate that George Monbiot has insinuated that one of us (Jim Hansen) is a believer in biochar as a "miracle" solution for the climate crisis. If he is basing this on our published papers, then he has grossly misunderstood them. An attentive reader would know his insinuation is false by simply examining our land use-related assumptions in our recently published peer-reviewed paper, Target atmospheric CO2: Where should humanity aim?
Broadly speaking, our climate change mitigation scenarios are strictly illustrative in nature, in other words, they serve to convey the types, magnitude and time frame of mitigation measures needed to reduce atmospheric carbon dioxide amounts. Although we do mention waste-derived biochar as a possible mitigation option, it certainly does not mean we are advocating that as the panacea. Indeed, as we very clearly outline in the paper, our scenarios assume waste-derived biochar provides only a very small fraction of the land use-related CO2 drawdown, with reforestation and curtailed deforestation providing a magnitude more. Nowhere do we assert or imply plantations should be grown specifically for biochar, or that reforestation should be at the expense of food crops, pristine ecosystems or substantially inhabited land. Furthermore, all relevant numbers used in our mitigation scenarios are derived from the peer-reviewed scientific literature.
On the issue of land use changes in general, our paper clearly states any biofuels approach must be very carefully designed, and we cite two major critiques of current biofuels approaches. We agree there are still fundamental uncertainties associated with biochar as a mitigation option, but the peer-reviewed papers we cite describe these uncertainties.
Monbiot's piece might leave readers with the impression that human-assisted reforestation is a lose-lose situation everywhere on the planet. However, there are numerous scientific assessments that indicate there are hundreds of millions of hectares of suitable, sparsely inhabited lands — lands degraded by human activities in the first place. Given that reforestation occurs on a large scale even in nature (for example natural succession), it makes perfect sense to promote sensible, anthropogenic reforestation, among other reasons to undo the damage caused by large-scale deforestation.
Pushker Kharecha and Jim Hansen are at the Nasa Goddard Institute for Space Studies and Columbia University Earth Institute
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Response from Monbiot
25 Mar 09,
Dear Jim,
I accept that (unlike some of the other people I mentioned) you are not advocating the creation of biomass plantations. But I believe that you might still be making a wrong call here.
Yes, I based what I said on the paper you reference: Target atmospheric CO2: Where should humanity aim? In it you say:
"Replacing slash-and-burn agriculture with slash-and-char and use of agricultural and forestry wastes for biochar production could provide a CO2 drawdown of ~8 ppm or more in half a century [85]."
In the Appendix to the paper you note that:
"Waste-derived biochar application will be phased in linearly over the period 2010-2020, by which time it will reach a maximum uptake rate of 0.16 GtC/yr."
I note that neither in the paper nor in the Appendix do you produce an estimate for the amount of plant material required to supply 0.16GtC/yr, or seek to determine how much of this could be provided by agricultural or forestry wastes.
Chris Goodall, in the book I referenced, proposes that to create 0.4GtC of charcoal we'd need to process about 1.6Gt of biomass. This, he suggests, requires dedicated biochar production across 200m hectares. If his ratios are correct, your proposal would require waste products equivalent to annual dedicated biomass production across 80m hectares. Do such quantities of available waste exist? And how much of it is genuinely available, and genuinely waste? (ie not earmarked for composting/ploughing in/animal bedding, cooking fuel/other forms of biomass burning etc).
Are you in danger of setting up a target which cannot be met by the means you propose?
As for "slash-and-char", if this were to be supported by carbon credits or some other financing mechanism, would that not create a powerful incentive for deforestation - effectively subsidising slash and burn farming?
Best wishes,
George Monbiot
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response from Kharecha
25 Mar 09
George,
Pushker Kharecha here, Jim's co-author on the 'Target CO2' paper who was responsible for devising the mitigation scenarios.
Re your comments above (3/25/09, 2:22 pm)...First, I think you still might be misunderstanding the nature of our scenarios. As we mention above, they are purely illustrative in nature (as are all such scenarios), thus we are not suggesting that it's absolutely necessary to include biochar in mitigation efforts. The basic point is that fossil fuel emissions reductions alone will not be sufficient to achieve our atmospheric CO2 target of 350 ppm within this century, i.e. we will need to maintain existing biospheric CO2 uptake capacity (by ending deforestation) and restore human-degraded lands (by reforestation, enhancing soil carbon storage, etc.).
As we also mention in the above posting, in our scenarios we assume that the combination of curtailed deforestation and enhanced reforestation are over an order of magnitude greater than that of waste-derived char. This was precisely to acknowledge the fact that these strategies have already proven successful on the necessary scales (when devised properly of course), whereas large-scale char use is still fraught with uncertainties. The bottom line is that even if we omitted the char component from our scenarios, the land use-related CO2 drawdown would be virtually unaffected. If one were looking for substitutes for our char component, a perfectly viable one would be soil carbon sequestration via improved agricultural practices such as conservation tillage (which could actually provide an even higher contribution than the char value we assumed).
Re our specific assumptions for char that you've referred to here, first note that by 'waste-derived biochar', we mean precisely that, i.e. char which is produced from material that would have otherwise not been used (e.g., burned or placed in landfills instead). The value you're referring to (0.16 GtC/yr) is directly from a review paper in a refereed scientific journal (reference 85 in our Target CO2 paper). That review paper lists the following five *current* global sources of waste as the basis of the 0.16 GtC/yr value: forest and mill residues (0.04 and 0.05 GtC/yr, respectively); rice husks (0.04 GtC/yr); groundnut shells (0.002 GtC/yr); and urban waste (0.03 GtC/yr; this one is the most uncertain). All of these sources are assessed to have high/medium availability and suitability, and none of them would entail production of new biomass.
As for whether slash-and-char would encourage deforestation, that is obviously not our intent, nor is it a reasonable inference from our paper. As we state therein, we assume that deforestation is linearly phased out by 2015 (a lofty goal, but again, this shouldn't be taken too literally -- if it ends up not happening until say 2020 or so, that's not the end of the world). Furthermore, we suggest a price (tax) on carbon emissions that increases with time, thus any future deforestation would end up being substantially taxed, not subsidized. So the slash-and-char issue really would only apply to the period over which deforestation is being phased out. And just to clarify, note that slash-and-char was only mentioned in the main text -- it was not included in the mitigation scenarios (see Section 15 of the Supplement).
Regards,
Pushker Kharecha
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response from Monbiot:
25 Mar 09
Hi Pushker,
I take your points. What you say sounds reasonable to me.
Best wishes,
George
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Press Release: IBI Response to Recent Guardian Article on Biochar
March 25, 2009: For Immediate Release:
IBI has taken note of an article by George Monbiot in the UK Guardian on March 24, 2009 that questioned the validity of biochar as a climate mitigation tool and the scientists and others who support the development of biochar.
The Guardian has published responses from several of those biochar supporters mentioned by Mr. Monbiot, including James Hansen, Chris Goodall, and James Lovelock.
IBI sent The Guardian the response below written by IBI staff members Stephen Brick and Debbie Reed.
For more information, contact:
Stephen Brick, IBI Executive Director, sbrick5714@sbcglobal.net
Debbie Reed, IBI Policy Director, dcdebbiereed@yahoo.com
Thayer Tomlinson, IBI Communications Director, info@biochar-international.org
George Monbiot is right on the mark about our seemingly irresistible tendency for embracing miracle cures. And it is refreshing to have the press remind us that the laws of thermodynamics will continue to apply in our quest to reduce global carbon emissions. But his diatribe against biochar-like most such screeds-would have us throw the baby out with the bathwater.
This has been said often, but it needs to be said again: there is no magical pathway for cutting global carbon emissions. There is only a collection of steps-complex, costly, and, politically challenging. Put another way, there is no single remedy for the whole problem; but there are, very likely, one hundred different actions that can each bear one percent of the burden. Serious people have understood this for some time, and this would include, we believe, a large fraction of the general public that Mr. Monbiot presumably wishes to warn.
Biochar, produced and used appropriately, should be considered amongst the hundred. Done right, biochar produces four value streams: waste reduction, energy production, soil fertilization and carbon sequestration. Biochar can be made from animal manures and food processing wastes. These residuals are costly to those who produce them, and create greenhouse gas emissions if left untreated. Bio-gas and oil can be used for heating, generating electricity and transportation. Biochar can reduce the need for conventional, fossil-fuel based fertilizers. Finally, biochar can lock up carbon in the soils for extended time periods.
We don't have all the answers on biochar production and utilization; indeed, the mission of the International Biochar Initiative is to seek these answers, objectively and quickly. We know that there are bad ways to make biochar, that crop monoculture for producing feedstock is not a good idea, and that biochar does not affect all soils equally. None of this should rule biochar out of court, however, as we also are assembling a body of knowledge on how to produce and use biochars that are beneficial. In this way, biochar resembles many other carbon-cutting technologies that face uncertainties. In our case, all we seek is an opportunity to be heard fairly as we move towards Copenhagen.
We have no doubt that exaggerating the benefits of biochar is not helpful. On the other hand, the potential of biochar deserves serious consideration. Mr Monbiot's glib dismissal of this potential is unwarranted.
Stephen Brick is the Executive Director of the International Biochar Initiative
Debbie Reed is the Policy Director of the International Biochar Initiative
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