Tag Archives: biochar

Biochar can help us keep climate change at bay and more food on the table, according to a new meta-study

Biochar — organic material baked in oxygen-starved environments — can help power up the agriculture industry while also fighting against climate change, according to a new paper.

Image via Wikipedia.

Coal is naturally produced underground, over millions of years, from ancient biomass. This organic matter that got buried in some way or another was then compressed and heated up through geological processes, which broke down its original structure and increased its carbon content. Biochar is produced in a very similar way, but instead of letting natural (and slow) geological processes cook it up, we make it ourselves.

This material can help fertilize soils and, thus, increase crop yields. At the same time, by preventing the carbon within it from being released back into the atmosphere, the use of biochar in agriculture can help fight climate change.

Very, very, very well done

“Biochar can draw down carbon from the atmosphere into the soil and store it for hundreds to thousands of years,” says Stephen Joseph, lead author of the paper, and a Visiting Professor in the School of Materials Science and Engineering at the University of New South Wales Science. “This study also found that biochar helps build organic carbon in soil by up to 20 percent (average 3.8 percent) and can reduce nitrous oxide emissions from the soil by 12 to 50 percent, which increases the climate change mitigation benefits of biochar.”

Biochar is a product usually made from aggregated organic waste — a mixture of waste biomass from agriculture, forestry, and household sources. For such an unassuming substance, it could lend a sizable hand towards fighting climate change and us having more food, according to a new paper. The findings are supported by the Intergovernmental Panel on Climate Change’s recent Special Report on Climate Change and Land, which estimated there was important climate change mitigation potential available through biochar. This report estimated that biochar use “could mitigate between 300 million and 660 million tons of carbon dioxide [globally] per year by 2050,” Prof. Joseph explains.

“Compare that to Australia’s emissions last year—an estimated 499 million tons of carbon dioxide—and you can see that biochar can absorb a lot of emissions. We just need a will to develop and use it.”

The meta-study reviewed 300 papers on the topic, including 33 meta-analyses that together reviewed around 14,000 biochar studies that have been published over the last 20 years. According to its result, the use of biochar, when mixed-in with crop soils, can boost yields by 10% to 42%, reduce the levels of heavy metals in plant tissues by between 17% and 39%, and increases the bioavailability of phosphorus, a critical nutrient that often acts as a bottleneck for the development of plants.

All in all, its use helps plants grow faster and larger, while also helping them better resist environmental stresses such as toxic metals, diseases, organic stressors such as herbicides and pesticides, and water stress.

The paper also explains how biochar acts on the roots of plants, boosting them. In the first three weeks of a plant’s life, it explains, biochar particles react with soils and stimulate germination (i.e. it helps seeds ‘catch’) and the development of the fledgling plant. Over the next six months or so, biochar particles in the soil form reactive surfaces which help draw nutrients towards the roots. As these particles start to age, something that happens around three to six weeks after being mixed into the soil (depending on environmental conditions), they break down and form microaggregates with other chemicals. This, in turn, helps protect roots and prevents the decomposition of organic matter.

Biochar yielded the best effects when used in acidic or sandy soils together with fertilizers, the authors explain.

“We found the positive effects of biochar were dose-dependent and also dependent on matching the properties of the biochar to soil constraints and plant nutrient requirements,” Prof. Joseph says.”Plants, particularly in low-nutrient, acidic soils common in the tropics and humid subtropics, such as the north coast of NSW and Queensland, could significantly benefit from biochar.”

“Sandy soils in Western Australia, Victoria and South Australia, particularly in dryland regions increasingly affected by drought under climate change, would also greatly benefit.”

Prof. Joseph has been studying the use of biochar ever since he was introduced to the practice by Indigenous Australians in the seventies. He explains that these people, alongside indigenous groups in Australia, Latin America (especially in the Amazon basin), and Africa, have been using biochar to maintain soil health and improve crops for centuries. Despite this, it hasn’t really been adopted as a commercial product, and most countries only produce a small amount of biochar every year.

To really make an impact, he explains, biochar needs to be integrated with farming operations on a wide scale. The first step towards that, he feels, is to tell farmers that biochar is an alternative they can opt for, and establish demonstrations so farmers can see that the benefits are real, not just words.

“This is in part due to the small number of large-scale demonstration programs that have been funded, as well as farmers’ and government advisors’ lack of knowledge about biochar, regulatory hurdles, and lack of venture capital and young entrepreneurs to fund and build biochar businesses,” he explains. “We’ve done the science, what we don’t have is enough resources to educate and train people, to establish demonstrations so farmers can see the benefits of using biochar, to develop this new industry”.

The paper “How biochar works, and when it doesn’t: A review of mechanisms controlling soil and plant responses to biochar” has been published in the journal GCB Bioenergy.

Biochar could be key to rebuilding the Amazon forest

Credit: Wake Forest University.

Over the past few weeks, the world has witnessed in horror as the Amazon rainforest became engulfed in devastating fires. Besides fire, the Amazon’s iconic canopies are constantly being besieged by land clearing for agriculture, logging, and mining. However, scientists are researching ways to rebuild the rainforest.

Writing in a new study, researchers at Wake Forest University’s Center for Amazonian Scientific Innovation (CINCIA) found that biochar — charcoal used in soil amendment — is a cheap and effective material that can improve tree seedling survival during reforestation efforts.

The first few months following transplanting are the most vulnerable in a tree seedling’s life, but the researchers found that adding just a bit of biochar improves the soil, thereby improving the survivability of the seedlings. Adding fertilizers gives maximum results, the researchers found.

Biochar is beneficial for the soil, allowing it to retain more water and become less acidic. Biochar is also a great environment for microbes, which aid plant growth. Finally, biochar holds fertilizer and releases it over time. This winning combo decreases the need for repeat application of fertilizer, thereby lowering replanting costs.

For their study, the research team used soils from the San Jacinto native community in Peru, whose lands have been affected by gold mining. When the researchers led by Miles Silman analyzed this particular soil, they found that it was devoid of organic matter and microbes.

After adding biochar and fertilizers to two tropical tree species (Guazuma crinita and Terminalia amazonia) grown in the depleted soil, the researchers found that they could “fix” the damaged soil.

“We show that while both biochar and fertilizer can improve tree seedling growth, combining them makes seedlings thrive beyond either amendment alone,” said Silman.

The study suggests that biochar is excellent for recovering soil from areas damaged by gold mining.

“These are the kinds of landscapes we have to recover, and we are still trying to determine how to grow plants in them,” Silman said. “This soil is extremely limiting for natural regrowth, but treating them with biochar turns it into something that plants can grow in. That’s good for biodiversity and good for the people that have to make a living from the land.”

The findings appeared in the journal Forests.

New tech transforms human poop into clean biofuel

Credit: Pixabay.

Millions of people living in the developing world face a double challenge: sanitation and energy generation. Researchers at Ben-Gurion University of the Negev (BGU), Israel, have killed two birds with one stone by developing a solution that turns human excrement into hydrochar, a readily-available fuel.

Dirty waste to clean fuel

According to the World Health Organization (WHO), 2.3 billion people still lack basic sanitation service. Of these, approximately 892 million people defecate in the open. Defecating outdoors bears a significant risk of contamination to the fresh water supply and is associated with the death of 700,000 children each year who contact diseases like diarrhea.

Exposure to germs not only puts children at risk of developing diseases but, over the long term, can also cause changes in the tissues of their intestines that prevent the absorption and use of nutrients in food — even when the child does not seem sick. A report authored by the World Bank found a link between open defecation and poor cognition among children. As such, open defecation threatens the human capital of developing countries.

“Human excreta are considered hazardous due to their potential to transmit disease,” said lead-author Prof. Amit Gross.”While it is rich in organic matter nutrients such as nitrogen, phosphorus and potassium, human waste also contains micro pollutants from pharmaceuticals, which can lead to environmental problems if not disposed or reused properly.”

BGU researchers sought to address this major world health issue by utilizing a process called hydrothermal carbonization (HTC). Inside a system that resembles a pressure cooker, the team heated raw solid human waste to three temperatures (180, 210, and 240° C) and reaction times (30, 60, and 120 minutes), which dehydrated the excrement, producing a solid known as hydrochar and a nutrient-rich liquid. Previously, the BGU research team had worked on poultry excrement.

Hydrochar produced from wood sample (Euc Amplifolie). Credit: Fang et al, Journal of Industrial and Engineering Chemistry.

Hydrochar produced from wood sample (Euc Amplifolie). Credit: Fang et al, Journal of Industrial and Engineering Chemistry.

Hydrochar is very similar to biochar, with some notable differences. While both are stable, carbon-rich solid by-products, the two chars have significantly different physiochemical properties that affect their potential applications. These include but is not limited to carbon sequestration, soil amelioration, bioenergy production, and wastewater pollution remediation. While biochar is the result of slow-pyrolysis (essentially burning without a flame), hydrochar is produced with hot compressed water instead of drying. Another advantage is that HTC yields higher amounts of char and uses lower amounts of energy than pyrolysis.

Hydrochar can be used as coal, for household heating and cooking, replacing wood. Used this way, hydrochar lessens the carbon footprint of communities by preventing deforestation, soil erosion, and greenhouse gas pollution. Due to the high temperatures involved in HTC process, the resulting hydrochar is sterilized and safe to handle. The aqueous byproduct can be employed as fertilizer, the authors reported in the Journal of Cleaner Production.

It remains to be seen how this technology can be brought to scale to those who need it the most. In the meantime, with World Toilet Day just around the corner (November 19), it’s good to take a moment to appreciate the invention that saved the most lives in history: the flushing toilet.

carbon negative

Carbon negative: removing CO2 altogether from the atmosphere

As climate change and global warming become ever pressing issues on the desks of the world’s governments, so do the much awaited measures become more prevailing, albeit not nearly as thoughtfully as they should be addressed. Today, renewable energy sources like solar and wind have actually ceased to become regarded as “alternative”, since actually more capacity of renewable energy was added than other in both the United States and in Europe.

Whether you choose to believe in human induced climate change or not, the truth of the matter is, no matter what side of the fence you’re on, growing carbon dioxide emissions in the atmosphere signify a grave peril to humanity, life on Earth and nature’s balance.

(c) http://bellona.org

(c) http://bellona.org

Efforts to curb emissions levels have gone a long way in the past few decades, and for this we can only be grateful to all the engineers, scientists, and not lastly government officials who had the vision and courage to listen and voice the right measures for the good of our planet and generations to come.

Still…with all this measure at play, in the year 2011 global greenhouse gas emissions reached a new record, since developing countries are burning fossil fuels at an alarming rate as they seek to level the game with other developed countries. It’s becoming clear than reducing emission isn’t enough.

Recently, Stanford University released a report in which it highlights solutions for cutting carbon emissions, as in removing them altogether, instead of simply reducing them, as part of the university’s Global Climate and Energy Project (GCEP). These methods and solutions are commonly referred to as carbon-negative technologies, and some of them have been described in the report.

“To achieve the targeted cuts, we would need a scenario where, by the middle of the century, the global economy is transitioning from net positive to net negative CO2 emissions,” said report co-authorChris Field, a professor of biology and of environmental Earth system science at Stanford. “We need to start thinking about how to implement a negative-emissions energy strategy on a global scale.”

Negative carbon means a more positive environment

Negative carbon emission occurs when more carbon is sequestered than it is released in the atmosphere, and of the technologies that can allow this is s BECCS, or bioenergy with carbon capture and storage. Typically, BECCS converts woody biomass, grass and other vegetation into electricity, chemical products or fuels, such as ethanol. Where it shines however is in it capability of trapping carbon.

In a way, the system is very similar to how plants work. During photosynthesis plants absorb carbon dioxide and store it, before releasing it back in the atmosphere when the plants dies and decays. With BECCS however, the captured carbon doesn’t need to be released back, instead it can be stored underground.

In the GCEP Stanford report, a conclusive example is being given in the form of a Department of Energy sponsored corn ethanol production facility in Decatur, Ill. Here,  some 1,000 metric tons of CO2 emitted during ethanol fermentation are captured and stored in a sandstone formation some 7,000 feet underground. Ultimately, the goal of the project is to sequester 1 million metric tons of CO2 a year – the equivalent of removing 200,000 automobiles from the road.

Estimates show that by 2050, BECCS technologies could sequester 10 billion metric tons of industrial CO2emissions annually worldwide. This, of course, if the technology is backed up by solid investment.

 “To meet ambitious climate targets, a cost-effective policy would be to implement a carbon tax and to recycle the revenues to subsidize captured emissions from biomass,”  said Olivia Ricci of the University of Orléans in France.

Biochar and other carbon-negative technologies

Another carbon-negative technology, rather similar to BECCS but with distinct differences, is biochar. Similar to charcoal, biochar is the byproduct of plants, only it is produced through the heating of vegetation without oxygen, a process typically referred to as pyrolysis. Carbon-rich chunks of biochar are thus made that can be put in the soil trapping the carbon, while acting as a soil fertilizer at the same time.

Biochar systems can be net negative if the biochar is made from waste biomass, sustainably harvested crop residues or crops grown on abandoned land that has not reverted to forest. On a global scale, using biochar could result in the sequestration of billions of metric tons of carbon a year, however scientists warn that biochar instability might occur if concentrations are too great. I recommend reading my colleague’s piece on how biochar could save millions of lives, for more info on the subject.

 “Estimates of biochar half‐life vary greatly from 10 years to more than 100 years. The type of feedstock also contributes to stability, with wood being more stable than grasses and manure,” the authors of the report write.

Sequestrating carbon in the ocean has been a proposal for many years, and is also considered a viable solution discussed in the raport. Today, ocean acidification  is a matter of great concern, as an increased uptake of atmospheric COcauses seawater to become more acidic, putting the ecosystem at great peril. It is believed ocean acidification is reaching a 300 million year old peak, something that might trigger the extinction of massive amounts of marine life.

The authors cited research by David Keith of Harvard University suggesting that magnesium carbonate and other minerals could be added to the ocean to reduce acidity and sequester atmospheric CO2 absorbed in seawater in the process.

Like in the case of biochar, however, sequestrating immense amounts of carbon in the world’s oceans is a rather extreme measure and the full effects of such an endeavor are yet to be fully understood. “The associated risks to the marine environment need to be adequately assessed,” the authors concluded.

Other technologies discussed in the report, which can read in full here, are carbon-negative large agricultural systems and “artificial trees”.

source: Stanford.

Biochar stoves could save millions of lives, improve soil and air quality

Open-fire stoves represent the biggest domestic environmental threat today, killing 3.5 million people a year—more deaths than caused by malaria and HIV/AIDS combined. But now, cookstoves that produce biochar could provide a viable alternative, saving millions of lives and giving a boost to local agriculture.


Cookstoves are common in many parts of the world, from Europe (mostly Eastern Europe) to Africa and the Americas. The picture above illustrates a family using such a device in western Kenya. At the same time, Gloria Torress Buitrago, a member of the Amburi indigenous community in southern Costa Rica has the same problem:

“It was hard to look around and just breathe without feeling the smoke burning the eyes or throat,” Buitrago said; one of her cousins is suffering from asthma, and the entire family is suffering more or less from respiratory conditions.

It’s estimated that half of the people in the world, over 3 billion people, use this kind of cookstoves! They virtually always cause some problems, problems which can vary from unpleasant to life threatening. A new, cleaner, but still cheap type of cookstove could do wonders for users’ health, but it can do even more – it can clean the air and enrich the soil. How so? The answer is simple: biochar.

Biochar is a a name for charcoal when it is used for particular purposes, especially as a soil amendment. Like all charcoal, biochar is created by pyrolysis of biomass – mostly wood. Biochar can not only contribute and improve mineral depleted (or just poor soil), but it can also fight global warming and clean up the air, by basically storing CO2.


Salim Mayeki Shaban, working at the African Christians Organization Network (ACON) explains:

“[Women] reported that the reduction of smoke in the house decreased irritation of their and their children’s eyes, runny noses, coughing, chest discomfort, and difficulties in breathing, along with cost savings due to fewer hospital visits,” Shaban said in an email.

But the hook here is the biochar; households can make $15-20 per month by selling the biochar produced by their cookstoves to several companies who are interested in buying this resource. It may not seem like much, but if you’re living in Kenya, the odds are it is. The biochar is used in research and studies, as well as in cacao farms, large organic nurseries, and garden projects.

“All the applications made of biochar increased total soil carbon amounts, as well as soil organic matter, gains which were stable even after one year of implementation,” Hojah da Silva said. “These gains are expected to be a persistent beneficial long-term effect.” SeaChar will continue to study the effects of biochar on soil in the coming year, Donnelly said.

Via National Geographic