[Terrapreta] my report on the agrichar conference

[kelpie at starband.net]

FYI - my article on the agrichar conference was published on truthout.org
yesterday - please let me know what you think.
-kelpie

http://www.truthout.org/docs_2006/050307R.shtml

 Birth of a New Wedge
    By Kelpie Wilson
    t r u t h o u t | Report

    Thursday 03 May 2007

    Terrigal, New South Wales, Australia - As delegates met in Bangkok
this week to debate climate change solutions contained in the IPCC's
latest report, one technology not mentioned in the draft report was
being closely examined at a conference in Australia in the beach town
of Terrigal, just north of Sydney.

    The first meeting of the International Agrichar Initiative convened
about 100 scientists, policymakers, farmers and investors with the
goal of birthing an entire new industry to produce a biofuel that goes
beyond carbon neutral and is actually carbon negative. The industry
could provide a "wedge" of carbon reduction amounting to a minimum of
ten percent of world emissions and possibly much more.

    Agrichar is the term not for the biomass fuel, but for what is left
over after the energy is removed: a charcoal-based soil amendment. In
simple terms, the agrichar process takes dry biomass of any kind and
bakes it in a kiln to produce charcoal. The process is called
pyrolysis. Various gases and bio-oils are driven off the material and
collected to use in heat or power generation. The charcoal is buried
in the ground, sequestering the carbon that the growing plants had
pulled out of the atmosphere. The end result is increased soil
fertility and an energy source with negative carbon emissions.

    Prominent Australian scientist Tim Flannery, who has written a book on
global warming called "The Weather Makers," was on hand to give
encouragement to the conferees. "I am deeply committed to your
solution," he told the group. In a keynote address, Flannery provided
an update on the acceleration of global warming, from the rapidly
melting Greenland ice sheet to the unprecedented drought that has
gripped Australia.

    Because the pace of global warming already exceeds projections,
Flannery is convinced that the world must do more than just reduce
emissions; we must find ways to rapidly remove CO2 from the
atmosphere. According to many researchers at the conference, agrichar
has the potential to store billions of tons of carbon safely away in
soils.

    The attendees were clearly excited by this potential, and, unlike
other meetings concerned with climate change, an electric buzz of
optimism was in the air. Joe Herbertson, director of a consulting
company called Crucible Carbon, said, "When I heard about this
technology, the hairs went up on the back of my neck. This is the best
news on climate change I've ever heard."

    One reason for the excitement is agrichar's potential to address a
range of problems from poor soil fertility to waste disposal to rural
development. About half the world's population relies on charcoal for
cooking fuel, and the production of charcoal drives deforestation in
Africa and other places. Smoky, inefficient charcoal kilns pollute the
air with noxious gases that harm health and heat the planet.

    An effort to replace these kilns with modern, efficient pyrolysis
units would relieve the pressure on forests by reducing waste and
adding the ability to use any source of biomass, including
agricultural waste products such as rice hulls. The ultimate objective
is to produce enough charcoal to have some left over to bury and
increase soil fertility, leading to a bootstrapping effect where
increased yields provide both more food and more biomass for energy.

    Projects discussed at the agrichar meeting ranged from a
household-size pyrolyzing stove that produces both cooking gas and
charcoal, to industrial-scale units capable of processing large waste
streams from sugar mills, pulp mills, poultry farms and even
municipalities.

    Some participants suggested that energy, rather than agriculture,
would be the key driver for adopting biomass pyrolysis. There is a
tradeoff between producing energy or charcoal, as the process can be
optimized for either one. Desmond Radlein of Dynamotive Energy Systems
said, "It is wishful thinking that people will switch to renewable
fuels unless it is cheaper. All of this is tied to the price of oil;
as it goes up, many more things are possible." Because it costs money
for transport and the labor to put agrichar into soil, Radlein feels
that the path forward lies with biomass energy plantations fertilized
by agrichar, which will become a self-sustaining loop pumping carbon
into soils, paid for by the energy yield.

    Robert Flanagan, an entrepreneur working in China, had a different
view. There are 700 million farmers in China, he pointed out. China
could quickly deploy a small, village-level pyrolysis unit he is
developing, and because labor is cheap, spreading the agrichar on
fields would be affordable even without a large energy harvest.

    Others at the conference felt that an expanding market for carbon
credits under the Kyoto protocol would be the force that drives the
adoption of agrichar. Mike Mason, director of the UK biomass company,
Biojoule, said the impact of agrichar on nitrous oxide emissions alone
would be enough incentive to fund the needed projects.

    Nitrous oxide is 270 times more potent than CO2 as a greenhouse gas
and it lasts for 150 years in the atmosphere. Use of nitrogen
fertilizers is a major source of the gas, and a difficult one to
mitigate. But agrichar applied to fields seems to have a significant
damping effect on nitrous oxide emissions. Lukas Van Zwieten, a
researcher at the New South Wales Department of Primary Industries,
looking at preliminary results of his field trials measuring nitrous
oxide emissions from agrichar amended soils, said "the more I look
into this, the more excited I get."

    Several farmers attending the conference were primarily interested in
the increased yields possible with agrichar. Australia has some of the
poorest soils in the world - 75 percent of Australia's soils have less
than one percent carbon.

    The exceptional properties of charcoal in soil were first noticed in
the Amazon where there are large areas of what is called "terra preta"
or Amazonian dark earths. These dark earths can be several feet deep
and contain up to nine percent carbon, as compared with nearby soils
that have only about half of one percent. In one of the most
fascinating aspects of this story, the terra preta soils turn out to
have been deliberately created by a lost Amazonian civilization. Some
of the areas have been dated going back to more than 7,000 years, and
they are still highly fertile.

    Field trials and experiments in pots show impressive yield gains in
charcoal-amended soils, but so far researchers don't completely
understand why. One question is whether the effect is primarily
chemical and physical or primarily biological. Charcoal is a highly
porous material that is very good at holding nutrients like nitrogen
and phosphorus and making them available to plant roots. It also
aerates soil and helps it retain water.

    Charcoal's pores also make excellent habitat for a variety of soil
microorganisms and fungi. Think of a coral reef that provides
structure and habitat for a bewildering variety of marine species.
Charcoal is like a reef on a micro-scale.

    One of the research papers presented at the conference documented an
increased diversity of beneficial microbes in terra preta soils as
compared with unamended soils, but there are still no answers about
whether the fertility increase is due to physical or biological
factors. The best answer may be that it is both.

    One very evident tension at the conference was between the scientists
who are trying to better understand how agrichar works, and the
farmers and investors who want to apply the technology as soon as
possible. But one obstacle to deploying agrichar is the ability to
quantify its effects in order to create both a reliable product for
farmers and a solid guarantee of agrichar's carbon-fixing capacity for
the carbon-trading market.

    To that end, one of the most important research questions is how long
the charcoal stays fixed in the soil. It's important to distinguish
char, or black carbon, from soil organic carbon that comes from adding
compost, manure or crop residues. According to John Gaunt of Cornell
University, this kind of fresh organic matter does not stay in the
soil but is almost all released back into the atmosphere as CO2 within
ten years. For this reason, soil organic carbon has not qualified as a
carbon emissions reduction that would be tradable under the Kyoto
protocol.

    Johannes Lehman, also of Cornell, is attempting to determine what
percentage of the char stays fixed in the soil. Some of it does
oxidize, he says, but it's difficult to say how much. He believes that
agrichar-amended soils will see an initial period of weathering, after
which they will be stable for long periods.

    Certainly the existence of the terra preta soils in the Amazon is
testimony to the long-term carbon-fixing ability of agrichar, and
several conference participants felt that it would be best to settle
on a conservative amount of guaranteed carbon fixation and move as
quickly as possible to get policy in place to qualify agrichar as a
tradable form of emissions reduction.

    The feeling in Terrigal was universal that there is no time to waste
in deploying the agrichar wedge as a global warming solution.

    However, there were some additional cautions sounded about the
potential for abuse, especially the pitfall of all biomass schemes -
the danger that too much of the planet's land will be appropriated for
human needs and not enough left for other species. Mark Glover of
Renewed Fuel said that the source of biomass must be carefully
determined and that it would not do to repeat the mistakes of the palm
oil industry, which is rapidly deforesting the habitat of orangutans
in Indonesia, or the American corn ethanol industry, which has ended
up pricing tortillas out of the reach of Mexico's poor.

    Mike Mason of Biojoule expressed concern over the quantities of
biomass needed, but he said that if properly phased in, agrichar can
be the solution we are all looking for. First, he said, we must take
the four billion tons of agricultural waste products produced every
year and turn as much of that as possible into char and bury it in
soils to increase soil fertility. After a few years, as the
productivity of our fields rises, we can begin optimizing biomass
pyrolysis for energy production to help replace coal and fossil fuels.
Eventually, as our energy supply becomes decarbonized and we move more
and more to rely on solar, wind and ocean power, we can shift biomass
utilization back to char again and keep sequestering more carbon to
get atmospheric levels back to pre-industrial levels.

    In addition to directing Biojoule, Mason is also the founder of
Climate Care, a highly successful voluntary carbon-offset program that
supports renewable energy projects in the developing world, so he is
one of those visionary people who also knows how to make things
happen.

    By the end of the conference, after the participants had considered
the political and economic obstacles to the vision, there was a bit of
sobering up, but not much. Robert Flanagan set up one of his
pyrolyzing wood cookstoves out on the beach and the scientists and
entrepreneurs quaffed beer and roasted marshmallows over the smokeless
glowing coals. Occasionally the stove would belch a sudden puff of
foul smoke and Flanagan would rush to adjust the downdraft control.

    After an hour or so, Flanagan opened the stove and dumped a few chunks
of charcoal out onto the sand. Those small morsels of black lying on
the white expanse of sand might symbolize the embryonic state of their
movement, but for most of the conference participants, agrichar was
still the best news they had ever heard.
------------

    Kelpie Wilson is Truthout's environment editor. Trained as a
mechanical engineer, she embarked on a career as a forest protection
activist, then returned to engineering as a technical writer for the
solar power industry. She is the author of Primal Tears, an
eco-thriller about a hybrid human-bonobo girl. Greg Bear, author of
Darwin's Radio, says: "Primal Tears is primal storytelling, thoughtful
and passionate. Kelpie Wilson wonderfully expands our definitions of
human and family."

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