Dec 5, 2008

World - Carbon: The Biochar Solution

Lisa Abend

On his farm in the hills of west virginia, Josh Frye isn't raising chickens just for meat. He is also raising them for their manure. Through a process that some scientists tout as a solution to climate change, food shortages and the energy crisis, Frye is transforming the waste into a charcoal-like substance called biochar that in the long run could be far better for the world than chicken nuggets. "It might look like this is just a poultry farm," says Frye. "But it's a char farm too."

Burn almost any kind of organic material — corn husks, hazelnut shells, bamboo and, yes, even chicken manure — in an oxygen-depleted process called pyrolysis, and you generate gases and heat that can be used as energy. What remains is a solid — biochar — that sequesters carbon, keeping CO2 out of the atmosphere. In principle, at least, you create energy in a way that is not just carbon neutral, but carbon negative.

And the benefits only begin there. When added to thin and acidic soil of the kind found in much of South America and Africa, char produces higher agricultural yields and lets farmers cut down on costly, petroleum-heavy fertilizers. Subsistence farmers seeking better soil have traditionally relied on slash-and-burn agriculture, which generates greenhouse gases and decimates forests. If instead those farmers slow-smoldered their agricultural waste to produce charcoal — in effect, slash-and-char agriculture — they could fertilize existing plots instead of clearing more land. This in turn would reduce emissions in the atmosphere, and so on in a virtuous circle of environmental renewal.

Could it really be that simple? It appears to have been for the original inhabitants of the Amazon basin. In the 16th century, Spanish explorer Francisco de Orellana wrote home describing the remarkably fertile lands he had discovered there. In the 19th century, American and Canadian geologists uncovered the reason: bands of terra preta (dark earth), which locals continued to cultivate successfully. Research revealed that the original inhabitants of the region had added charred wood and leaves — biochar — to their lands.

Centuries later, it was still there, enriching the soil. "You couldn't help but notice it. There would be all this poor, grayish soil, and then, right next to it, a tract of black that was several meters deep," says Johannes Lehmann, a soil scientist who worked in Manaus, Brazil, in the late 1990s. After he left the Amazon in 2000 for a job at Cornell University, N.Y., Lehmann started wondering what would happen if farmers today could make their own terra preta. He has found one answer in a field trial in Kenya, where 45 farmers achieved twice the yield in their corn crops with biochar than with conventional fertilizers.

Epidra, a private firm in Athens, Ga., is exploring larger-scale applications, such as pyrolysis systems that can produce both enough energy to power a tractor and a biochar tailored to improve particular soils. "If you're going to grow food, you have to do it responsibly," says Bob Hawkins, Eprida's project manager. "And one way of doing that is to use it to generate sustainable energy." A prototype can turn a ton of ground peanut shells into 600 lb. (270 kg) of biochar, with energy as the bonus.

Biochar's ability to sequester CO2 has given new urgency to such research. "Reducing emissions isn't enough — we have to draw down the carbon stock in the atmosphere," says Tim Flannery, chair of the Copenhagen Climate Council, a consortium of scientists and business leaders linked to next year's United Nations Climate Summit. "And for that, slow pyrolysis biochar is a superior solution to anything else that's been proposed." Cornell's Lehmann is even more emphatic. "If biochar could be massively applied around the globe," he says, "we could end the emissions problem in one to two years."

Not everyone agrees. "Biochar isn't a silver bullet, not by a long shot," says Dominic Woolf, a researcher at Swansea University in Wales. "You have to look at the big picture: pyrolysis itself produces carbon dioxide emissions, and you have to consider that when you try to determine biochar's capacity for sequestration." Lehmann says he welcomes the doubts, and notes that addressing them requires "investors willing to take the risk." Which is where chicken farmer Frye, with his small biochar operation, comes in as one of the few people out there actually making a business of it. With a pyrolysis unit that can create 3-4 tons of biochar a day, he generates enough energy to heat his hen houses; and he sells the char as fertilizer for $600 a ton. For Lehmann, biochar's benefits aren't so much a scientific novelty as a return to basics. "From cave drawings to iron smelting, charcoal has always played an important role in the development of civilization," he says. "Maybe it's about to do it again."

1 comment:

Erich J. Knight said...

Biochar, the modern version of an ancient Amazonian agricultural practice called Terra Preta (black earth), is gaining widespread credibility as a way to address world hunger, climate change, rural poverty, deforestation, and energy shortages… SIMULTANEOUSLY!

Modern Pyrolysis of biomass is a process for Carbon Negative Bio fuels, massive Carbon sequestration,10X Lower Methane & N2O soil emissions, and 3X Fertility Too.
Every 1 ton of Biomass yields 1/3 ton Charcoal for soil Sequestration, Bio-Gas & Bio-oil fuels, so is a totally virtuous, carbon negative energy cycle.

Charles Mann ("1491") in the Sept. National Geographic has a wonderful soils article which places Terra Preta / Biochar soils center stage.
I think Biochar has climbed the pinnacle, the Combined English and other language circulation of NGM is nearly nine million monthly with more than fifty million readers monthly!
We need to encourage more coverage now, to ride Mann's coattails to public critical mass.

Please put this (soil) bug in your colleague's ears. These issues need to gain traction among all the various disciplines who have an iron in this fire.
http://ngm.nationalgeographic.com/2008/09/soil/mann-text

I love the "MEGO" factor theme Mann built the story around. Lord... how I KNOW that reaction.

I like his characterization concerning the pot shards found in Terra Preta soils;

so filled with pottery - "It was as if the river's first inhabitants had
thrown a huge, rowdy frat party, smashing every plate in sight, then
buried the evidence."


Biochar data base;
http://terrapreta.bioenergylists.org/?q=node

I also have been trying to convince Michael Pollan ( NYT Food Columnist, Author ) to do a follow up story, with pleading emails to him

Since the NGM cover reads "WHERE FOOD BEGINS" , I thought this would be right down his alley and focus more attention on Mann's work.

I've admiried his ability since "Botany of Desire" to over come the "MEGO" factor (My Eyes Glaze Over) and make food & agriculture into page turners.

It's what Mann hasn't covered that I thought should interest any writer as a follow up article and your transition team

The Biochar provisions by Sen.Ken Salazar in the 07 & 08 farm bill,
http://www.biochar-international.org/newinformationevents/newlegislation.html

NASA's Dr. James Hansen Global warming solutions paper and letter to the G-8 conference, placing Biochar / Land management the central technology for carbon negative energy systems.
http://arxiv.org/ftp/arxiv/papers/0804/0804.1126.pdf

The many new university programs & field studies, in temperate soils; Cornell, ISU, U of H, U of GA, Virginia Tech, New Zealand and Australia.

Glomalin's role in soil tilth, fertility & basis for the soil food web in Terra Preta soils.

The International Biochar Initiative Conference Sept 8 in New Castle;
http://www.biochar-international.org/ibi2008conference/aboutibi2008conference.html

Given the current "Crisis" atmosphere concerning energy, soil sustainability, food vs. Biofuels, and Climate Change what other subject addresses them all?

This is a Nano technology for the soil that represents the most comprehensive, low cost, and productive approach to long term stewardship and sustainability.


Carbon to the Soil, the only ubiquitous and economic place to put it.

Michael Pollan is well briefed about Biochar technology, but did not include it in his "Farmer & Chief" article, but I'm sure Biochar will be his 8001th word to you.

Erich
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