15 Apr 2009

Will Biochar Save The Polar Bears?

By Ben Eltham
What the hell is biochar? Ben Eltham answers all your questions about the latest climate change techno-fix

With the recent dramatic collapse of the ice bridge to the Wilkins Ice Shelf in Antarctica, climate change is back in the headlines.

But Malcolm Turnbull and Coalition environment spokesman Greg Hunt think they have an answer: biochar. Many of the world's top climate scientists, including James Hansen, agree with them.

So what exactly is biochar? Will it work, and can it save us?

Essentially, biochar is charcoal — the burnt remains of organic material. The CSIRO has published a handy fact-sheet which explains that biochar is "a type of charcoal which results from the thermal treatment (heating) of natural organic materials (eg crop waste, wood chip, municipal waste, or manure) in an oxygen-limited environment. This process is referred to as pyrolysis."

The pyrolysis is the important part. Merely burning organic matter on a big bonfire won't give you biochar; limited oxygen and very high temperatures are required.

What biochar can do is sequester carbon. By turning typical organic molecules into carbon-containing aromatic rings, pyrolysis has the potential to be "carbon negative". This means the process can actually take up more carbon than it gives out, potentially reducing the amount of carbon in the atmosphere. It's the holy grail of climate change mitigation. No wonder Tim Flannery is into it.

But will it work? Proponents point to native Amazonian slash-and-burn farming practices, which appear to have produced the dark soils called terra preta that remain rich in soil carbon for thousands of years. Biochar can be produced quite easily using current technologies, and small-scale pyrolysis systems for use on farms are commercially available: the NSW Department of Primary Industries is researching a pilot biochar reactor in Gosford. Indeed, one of the biggest benefits of biochar might be to help subsistence agriculture in developing nations, for example in Central America.

But much research remains to be done. Dr Evelyn Krull, the author of the CSIRO's biochar fact sheet, told the ABC's Anna Salleh that it will take three to five years before CSIRO can recommend it to farmers. "What we don't know is what the safe upper limits of biochar applications are for different soil types," she told Salleh.

And, as with nearly all renewable energy technologies, there is the problem of scale. There is a vast difference between small-scale research plants and the kind of large-scale, industry-wide solutions that can make a difference to climate change. One of biochar's chief proponents, Cornell University's Johannes Lehmann, admits that the big question about biochar is "whether this approach can be scaled up to national and regional, or even global, scales."

The CSIRO's Evelyn Krull appears to agree, telling the ABC that estimates on how much carbon can actually be trapped using biochar are rubbery, at best. "I don't know where these numbers come from," she said.

One source of these optimistic figures is a 2009 paper by UK meteorologist Tim Lenton (based on work by Lehmann), which estimated that biochar technology might be able to sequester as much as 0.56 gigatonnes of carbon a year, globally. This really would make a big impact. At the moment, though, it's only a figure in a scientific paper.

So can biochar save us? Probably not. As George Monbiot has pointed out in The Guardian, the biggest problem with the biochar campaign may well be its allure as a miracle solution to global warming.

This has been a common human response to gigantic problems that threaten to overwhelm us. Ever since the Reverend Thomas Malthus wrote his gloomy tome An Essay on the Principle of Population, the standard retort of pragmatic conservatives and Panglossian optimists has been that humanity's ingenuity will enable us to innovate our way out of ecological disasters. The "game-changing" ability of technological innovation has indeed been a key factor in saving the world from starvation since Malthus' time — but at the cost of significant environmental degradation in many parts of the globe.

In the 1970s, we saw a re-run of the Malthusian debate with the publication of the Club of Rome's groundbreaking report, The Limits to Growth. Authored by a group of analysts from MIT, The Limits to Growth famously predicted that global ecosystems would eventually be overwhelmed by a "business-as-usual" approach to economic growth. It foreshadowed the depletion and exhaustion of crucial energy resources, and the "overshoot and collapse" of global population. Enjoying blockbuster sales at the time, the survey soon attracted strong criticism from economists such as Julian Simon, and has often been dismissed by skeptical optimists like Bjorn Lomborg as a case-study in the perils of doom-laden prediction.

Unfortunately, the Cassandras are looking more prescient than the Panglossians just now. A recent research paper by the CSIRO's Graham Turner looked at the projections of The Limits to Growth 30 years on, in the light of three decades of accumulated data. He found that the Club of Rome's business-as-usual (or "standard run") model was surprisingly accurate, giving essentially correct figures for things like global population, non-renewable resource depletion and global pollution.

One of the key criticisms of the Club of Rome's models was that technological innovation would solve many of the resource constraints it predicted. So far, this hasn't happened with fossil fuels like oil. Likewise, a series of renewable energy technologies have been mooted as the saviour of the global economy and environment. First it was solar energy. Then wind. Then more exotic renewables like geothermal and tidal power. And finally the mirage of "clean coal", or Carbon Capture and Sequestration, motivated governments and politicians (including in Australia) to invest billions in the hope of allowing humanity to burn dead trees forever. Time and again, commercial realities, political complacency and vested interests have defeated the promise of renewable energy industries. Biochar is, in this sense, simply the latest in the long line of such false dawns.

None of this is to say we shouldn't pursue biochar technology. As Chris Goodall wrote in The Guardian in response to Monbiot, "yes, we don't yet understand fully why biochar works but this is not an argument to ignore it or rule it out."

Clearly, if we are to seriously address the global crisis of anthropogenic global warming, we need every shot in the technological armoury. But biochar will never be enough. If we are to stave off ecological catastrophe this century, we are going to have to stop burning carbon.

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Posted Wednesday, April 15, 2009 - 23:48

I agree with Ben Eltham’s conclusion that biochar is PART of the "technological armoury" required to reduce the atmospheric concentration of 387 ppm CO2 (corresponding to a current CO2-equivalent concentration of about 450 ppm) to a safe sustainable circa 300 ppm. A recent study by UK scientists of bioengineering options to reduce CO2 had a similar conclusion (see: T.M. Lenton & N.E. Vaughan, The radiative forcing potential of various climate geoengineering options, Atmospheric Chemistry and Physics Discussions, 9, 2559-2608, 2009: http://www.atmos-chem-phys-discuss.net/9/2559/2009/acpd-9-2559-2009-prin... )

However George Monbiot (so correct on other key humanitarian and environmental matters) has got it wrong in condemning biochar as a threat to human food supplies (for a detailed rebuttal see see "Forest biomass-derived Biochar can profitably reduce global warming and bushfire risk ": http://sites.google.com/site/yarravalleyclimateactiongroup/forest-biomas... ).

In short, the key argument of Monbiot is that virtually ALL the arable land of the world would have to be used. However he has used a “straw man” argument in ignoring the circa 2 GtC/yr straw biomass from crops on arable land – he ignores a potential total of circa 12 GtC (billions of tonnes of C) of biomass for biochar annually from forestry, grassland and agricultural waste (notably straw biomass from 1.34 billion ha of arable land).

Of course Monbiot would be dead right (with dead being the operative word) if arable land were used not for growing food (with straw nbiomass as a useful biochar precursor side product) but for dedicated growing of biomass for biochar i.e. “food for biochar” as in the obscene and criminal “food for biofuel” that is currently legislated in the UK, US, EU and part of Australia.

On p224, Progress in Thermochemical Biomass Conversion, volume 1, IAE Bioenergy, ed. A,V, Bridgewater (Blackwell Science) (see: http://books.google.com.au/books?id=rdqGX0LEg7sC&pg=PA224&lpg=PA224&dq=G... ) informs us that we could obtain 1.7 GtC/yr (straw from agriculture) + 4.2 GtC/yr (total grass upgrowth from grasslands upgrowth) + 6 GtC/yr (possible sustainable woodharvest) = 11.9 GtC/yr.

From this one can see why biochar expert Professor Johannes Lehmann of Cornell University is correct calculating that it is realistically possible to fix 9.5bn tonnes of carbon per year using biochar, noting that global annual production of carbon from fossil fuels is 8.5bn tonnes C (see: Alok Jha, “”Biochar’ goes industrial with giant microwaves to lock carbon in charcoal”, Guardian (13 March 2009): http://www.guardian.co.uk/environment/2009/mar/13/charcoal-carbon and Johannes Lehmann, Biochar for mitigating climate change: carbon sequestration in the black”: http://www.geooekologie.de/download_forum/forum_2007_2_spfo072b.pdf ).

Top UK climate scientist Professor Lovelock FRS has the same position in his assessment: “This [biochar] is the one thing we can do that will make a difference, but I bet they won't do it” (see Gaia Vince (2009), “One last chance to save mankind“, New Scientist, 23 January 2009: http://www.newscientist.com/article/mg20126921.500-one-last-chance-to-sa... and http://biocharfund.com/images/hansen%2C%20target%20atmospheric%20c02.pdf ).

Peace is the only way but Silence kills and Silence is complicity.

Posted Thursday, April 16, 2009 - 07:09

This is an interesting idea. I've been discussing it for a year or so with some other people, but wasn't convinced on either
a) Its use as a nutrient 'locker' for farming/gardening or
b) Just how effective it would be to burn vegetative matter in order to lock up C to prevent CO2/CH4 dissipating into the atmosphere.

However, a few links here show that real work, at least, is being done to ascertain exactly what those figures might be. I'd be interested to know exactly where/how this process might work. Until now, I'd been told only of how to create it by wood/forest management (ie, coppicing, etc), but had never heard of straw (for example) and other biomass being able to be used.

It could be encouraging, as a significant tool in the box (provided it isn't compromised in ways such as biofuels have been - *replacing* food crops, and becoming a commercial commodity in itself). I don't have a great deal of hope that this won't happen. I can see it first becoming a valuable commodity, particularly for soil enrichment - if that actually works - and then being latched onto by countries/people looking to make a quick dollar by burning forests. If it does work as the advocates suggest, it *should* be supplied to seed soil for growing food, and not burying in old mines. But unless well thought out policies can be enforced (for example, the creation of biochar from approved sources paid for by govts, but the biochar distributed - as a govt service - for free), it might have as many problems as any of the more technological approaches.



Dr David Horton
Posted Thursday, April 16, 2009 - 15:02

Another suggestion I have seen is, instead of using terrestrial plants, to produce algae commercially and turn that into biochar. But this would mean putting a price on the biochar, only realistic if it does actually contribute to soil fertility, and if this contribution can be continued indefinitely (my guess would be that there would be a limit to the uptake by soils, particularly the thin soils of much of Australia, and that in addition it will certainly change the composition of the soil microflora and microfauna in unpredictable ways). The search for a magic bullet for climate change, enabling us to continue business as usual, has much in common with the search for a "god".

Posted Thursday, April 16, 2009 - 15:31

One aspect of Biochar systems are Cheap, clean biomass stoves that produce biochar and no respiratory disease. At scale, the health benefits are greater than ending Malaria.
A great example;


Also , I would like the BioFuelWatch folks to read the petition of 1500 Cameroon Farmers;

The Biochar Fund

The USDA-ARS have dozens of studies happening now to ferret out the reasons for char affinity with MYC fungi and microbes, but this synergy is solidly shown by the Japanese work, literally showing 1+1=4

This is what I try to get across to Farmers, as to how I feel about the act of returning carbon to the soil. An act of pertinence and thankfulness for the civilization we have created. Farmers are the Soil Sink Bankers, once carbon has a price, they will be laughing all the way to it.

Biotic Carbon, the carbon transformed by life, should never be combusted, oxidized and destroyed. It deserves more respect, reverence even, and understanding to use it back to the soil where 2/3 of excess atmospheric carbon originally came from. We all know we are carbon-centered life, we seldom think about the complex web of recycled bio-carbon which is the true center of life. A cradle to cradle, mutually co-evolved biosphere reaching into every crack and crevice on Earth.

It’s hard for most to revere microbes and fungus, but from our toes to our gums (onward), their balanced ecology is our health. The greater earth and soils are just as dependent, at much longer time scales. Our farming for over 10,000 years has been responsible for 2/3rds of our excess greenhouse gases. This soil carbon, converted to carbon dioxide, Methane & Nitrous oxide began a slow stable warming that now accelerates with burning of fossil fuel.

Biochar viewed as soil Infrastructure; The old saw; “Feed the Soil Not the Plants” becomes; “Feed, Cloth and House the Soil, utilities included !”. Free Carbon Condominiums with carboxyl group fats in the pantry and hydroxyl alcohol in the mini bar., build it and the Wee-Beasties will come. As one microbiologist said on the Biochar list; “Microbes like to sit down when they eat”. By setting this table we expand husbandry to whole new orders of life.
Thanks for your attentions,
Erich J. Knight
Shenandoah Gardens

Posted Thursday, April 16, 2009 - 16:11

Gideon, thanks for your contribution. I too have read Lenton's paper and it's a fascinating one. However it's important to note that scaling up technologies to mass-scale has been the big problem for nearly all other techs in the sector.

let's hope that biochar can make a difference.

This user is a New Matilda supporter. douglas jones
Posted Friday, April 17, 2009 - 16:16

douglas jones
Why must we continue to seek a silver bullet that will solve our problem of climate change, a one stop cure?
Assuming we have done enough talking to decide climate change is real and at least in part caused by combustion of carbon containing materials in the main. Oh yes Nitrous oxides and all the rest the e of CO2-e.

If not we can always use the profitable ideas relating to energy use given by Lovins work and the work of others. Lovins is at Rocky Mountain Institute and a lot of the work has been published as a book Factor Four. This will provide industry with the incentive of increased profit whilst lowering energy use.
Or of course we could continue with the idea of sequestering Coal emissions allowing financiers to make merry and industries given too generous allowances to make fortunes as they have done in Europe.

Of course we could continue talking waiting for the Club of Rome predictions to come to fruition.
The many millionaires from the latest scam can attempt their own salvation with site choice and local engineering.

Biochar is one of a number of possible partial solutions,the faithful see it as the solution Epidra even has figures showing it could be done. However even adding a solar water heater to every house would make some difference, but achievement will only come from the application of the many possible partial solutions already on offer.
Yes Biochar can improve the soil and hence crop yields particularly on poorer soils and yes it can retain nasties like pesticide residues nitrous oxides methane carbon itself in addition to its own carbon. Yes it can act as fertilizer, soil tilth improver improver of water holding capacity increase of pH. Most of all return the depleted Carbon to the soil reducing, as by product, atmospheric Carbon compounds.
It is being trailed in W A on field scale wheat crop and is produced in NSW at Best Energies in an experimental plant, proposed as means of removing biological waste otherwise going to land fill, investigated in many sites in Aust and the world. A small plant costs around 7 million a larger with through put of 39 tonnes per hour around 13 million. that is 136 tonnes C fixed per hour. Work continues on determining a biomass source which does not impinge on crop needs or clearing of yet more forest.
Clean coal has just been given 100 million for work leading, hopefully to fruition saving our export trade, very much down played by Guy Pearse in the latest Monthly essay in x years time where x is time which not only exceeds doing something now but passes 2020. That is near 8 biochar plants or many small using local biomass and providing the fuel for the transport plus char to increase yields of local farms.
International Biochar Institute has had a recent meet in the UK bringing together much of the findings see
Epidra a group who have done a lot of work have put a power point presentation at www.epidra.com/present.php4 go to the August 2008 site at the right. A picture of a biochar plant is given.
So no I do not expect biochar to be a solution on its own. I do think we will need cooperation of all citizens even those whose credo is profit and if we do not start soon we might as well give up and continue with our wars our financial scams consume till, we bust pretending we have found happiness and as time elapses and things get worse turn to way out religion and the blame game as to who did not or did what. naturally the whole idea of climate change might be wrong or might be a natiural even about which we can do very little.
I conclude we should keep talking some one will feel good if only temporarily.

Posted Saturday, April 18, 2009 - 02:37

What an unbelievable piece of stupidity. We have the good fortune to discover the perfect method of carbon sequestration so we burn it to liberate the carbon and then decide to put it back into the ground in a less stable form by burning something else to pack it into!
Who is fooling whom.
Is it really that we just don't get it. If coal can be regarded as Capital then why burn it if not to put it to use to create the next generation of Capital, the sustainable technology such as solar panels and wind machines? To simply burn coal for daily use as lighting, heating etc is to burn a Capital item which we presume to own at the expense of future generations. Where is our sense of custodianship. Are we all stupidly obsessed with the destruction of capital for the temporary short fix.
We destroy other forms of capital also, fertile land that we build houses upon.
What a wonderful way to sequestrate arable soil, lock it up for years as unproductive real estate.
The premature utilization of an idea is not the same as the utilization of technology, in which I believe the latter to mean a great understanding of the process.
The premature utilization of the idea of the Cane Toad in the Queensland Sugar Cane Industry was so reprehensible as we now see so regrettably but it is the perfect example to the oft used phrase " well if we make a botch of it the next group can either clean it up or improve upon it"
That is sloppy science and the next generation doesn't deserve it nor should they be presumed upon.
In medicine one of the earlier teachings was "Physician first do no harm". it is an enormous regret that other professions do not acknowledge or embrace that philosophy.
it is an offense to litter in the street yet it is not an offense to to pour effluent into the air, rivers and oceans or on land.
Also do the "economists" have carte blanche to do what is simple and easy if only to placate those whom they advise in the short term in preparation for the next election?
The most alarming distortion is to pretend that we don't need Capital we only need credit so we can live in a virtual reality in an ever expanding world that does not exist.
We will have to hope that some crazy aliens will land here and make offers for our debts that will exonerate our excesses.
The easy and present use of coal as a "cheap" resource as if it were just everlasting dirt forces upon us the need to have this deception that the solution is the continuous and uninterrupted use because the answer is only a short gap into the future.

Posted Sunday, April 19, 2009 - 00:02

so very high temperatures and limited oxygen are required, plus organic stuff to burn.
sounds like the engineers have been wooping up the cool aid to me. Take a bike...get real.

Posted Sunday, April 19, 2009 - 04:01

Hi Boxhead,

Actually, this one (compared to most) has been led, as I understand it, by the land workers, not engineers. Firstly, farmers in Brazil noticed the growing power of biochar, and started bagging and selling it. Secondly, people in various places got hold of this idea, had a poke about and decided it was biochar that had made certain Brazilian soil so productive. Thirdly, people started experimenting with it.

After positive feedback (on the soil health after biochar application - essentially charcoal soaked in urine/comfrey/manure stews), people figured out (scientifically or not, I don't know) that biochar might work as a way of fixing carbon/potential CO2, CH4, into the soil permanently, since the original in Brazil had been there for at least a couple of millenia.

Only very recently have (as far as I am aware) any real scientific studies been conducted in the potential of biochar for carbon sequestration. In Europe, at least, pro-active forest management has been going on for a very long time, so it is possible to harvest wood more proactively without being detrimental to the forests. In fact, in many parts, many native species actually *rely* on some such management (since the natural forest managers - beavers - were wiped out a hundred years or two ago).

So its not really an engineer's approach (or indeed, a scientific approach) - more the opposite way around. Not necessarily wrong, because a great deal of good common sense in forest/land management has been figured out over the millenia by people who never called themselves scientists, but, all the same, are being proved right in various ways even now. But not necessarily the cure-all many of these people are hoping for, either, if not for any other reasons bar political ones.

I've never tried biochar for my allotment - I will, one season, maybe soon. I'd like to speak with more authority on whether it works or doesn't, and the tests I've seen online by gardeners don't seem all that rigorous.

But, if it does work, and I can lug a pile of timber to the allotment, charcoal it, 'seed' it and plant it, and then nothing past composting for several years, I'll be happy with that - particularly when I can't just get a truck in to dump some manure.



Posted Tuesday, April 21, 2009 - 12:47

Thankyou Derek, that does make it clearer. I live in Phuket where the old habit is simply to burn all clippings wet or dry. Perhaps I can convince my neighbor to give Biochar a try and my lungs a break.

Posted Wednesday, April 22, 2009 - 01:04

"What an unbelievable piece of stupidity. We have the good fortune to discover the perfect method of carbon sequestration so we burn it to liberate the carbon and then decide to put it back into the ground in a less stable form by burning something else to pack it into!
Who is fooling whom."

In closed-loop Pyrolysis systems very little of the biomass is burnt. Pyrolysis is an exothermic reaction, once started it feeds itself. 1 ton of biomass typically becomes 1/3 ton char, 15- 20% each Bio-oil or bio-gas and the balance in process heat,
The Bio-oil or bio-gas, when used as fuel is the only release of CO2, but this is Carbon Neutral since it came from biomass not fossil fuel.
Erich J. Knight

Posted Tuesday, April 28, 2009 - 23:09

Sorry -erich- I should have more specifically stated that it was fossil fuel I was referring to when I wrote "perfect method of carbon sequestration".

For example has all fossil "fuel" reserves been estimated and calculated on the basis of how much should be rationed to the current population and how much has be quarantined for future generations or do they just get what's left because we could not use it fast enough?
It was simply to consider that the casual use of fossil fuel for immediate comfort and recreational use and not as an energy form to be used to develope the next level of energy producing technology fails to appreciate that it is a one time opportunity on such a large scale. To waste this cache for quick and simple profit and dissipation of a one off resource fails to comprehend it's true significance.
I suppose it could be seen in the context of throwing pearls before swine!

Fossil fuel to a an energy company is like farm land to a commercial land developer, the profound "self" interest is really an abomination to the true interpretation of Capitalism. In this instance both perpetrators have simply converted a capital item into an income to be dissipated.

This also impacts on the artificiality of the ability to support such a large population in this short term of abuse.
Battery hens ,now battery humans employed in factories to prove the theory of economists that growth is forever sustainable.
Homeostasis is sustainability.
Therefore one region after another has to set the level of long term sustainability and once achieved hope to assist other regions to reach their level.
This is a terribly boring prospect as it tries to eliminate the excitement of wars, recurrent boom and bust cycles of financial markets and of course the desire to get richer than our neighbour.
The current preoccupation with C02 and debt show how we collectively have absolutely no idea of the process of evolution and extinction.
We delude ourselves with the belief that creation theory will allow us to develope an endlessly expanding reality with unlimited resources.?

It is somewhat possible if one only considers one's own lifetime as the only timeline..