Dwelling on Drawdown – Part I

Last week marked my first big step in my latest project (and perhaps next book) which I’ve dubbed “dwelling on drawdown”. It involves researching, designing and building my forever home with an eye towards maximizing carbon sequestration and minimizing the use of fossil fuels in my c-sink sanctuary and surrounding yard. The scope will incorporate embodied carbon (for materials used during the build phase) and operating carbon (carbon used once the home is operating). My first big step consisted of attending an incredibly well-run week-long workshop where 43 folks from around the globe gathered to learn and help build a strawbale house. It was interesting, illuminating and a bit itchy!

Although my main focus for years has been on biochar, there are other materials that can also serve as C-sinks. Straw is one example, hemp another. According to one study, the ratio of carbon sequestration to weight of straw (at 10% moisture) is ~1.35:1.00. Using an average weight of 45 lbs/bale (60.76 lbs CO2), the house we built last week stored nearly 10t of Co2 (320 bales of straw were used). Factoring the embodied carbon (a life cycle assessment perspective) would require a lot more info on how the straw was harvested, transported, etc. Although the sequestration impact of wood is higher on a per pound basis (1.83:1.00 according to this study), the time value of carbon absorption ought to be factored in. Crop residues such as straw and hemp are especially appealing as they are annually renewable. The use of such residues also supports local farming communities.

Could biochar provide a larger carbon sink option per square foot for building walls? In all likelihood it could, but the current early stage of biochar building materials (e.g. bricks, mortar) makes building a predominantly biochar-based house a bit premature at this stage. I also appreciate that the full amount of carbon pulled from the atmosphere from wheat (or rice, barley, etc.) and hemp can be stored for long periods. When carbonized, you lose up to half of that carbon so these materials offer great carbon rebalancing opportunities when stored in buildings.

While the straw bale building process is generally quite sustainable, there are potential opportunities for biochar-based building materials to decarbonize some of the ancillary materials and processes used. Here are just a few ideas:

Roofing felt: we used a fair amount of roofing felt on both the interior and exterior walls, predominantly to cover wood and provide a more textured surface for applying plaster. Normally this material, also referred to as underlayment, tar paper (similar though not exactly the same) or membrane roofing, is used underneath asphalt shingles. The market is not trivial, supposedly $11B in 2016, no doubt this is due to its use in both reroofing and new construction. Roofing felt is a petroleum product; the cellulose felt is drenched in bitumen/asphalt to render it waterproof. It is on my hit list for elimination if at all possible as it comes with not only CO2 emissions during production, but VOC emissions after application.

Could we perhaps develop ‘char paper’ using bio-oil to facilitate water repelling properties? (To be honest, I have no idea if bio-oil can produce that type of result, but am happy to throw out the idea for chemists to ponder more profoundly.) Thicker carbon felt is already used for various things including fire resistant welding blankets, thermal insulators and more. Substituting lower cost biochar made from unloved organic material would provide a great opportunity for decarbonizing roofing materials.

Weed whip string – another aspect of straw bale building which could use a decarb make-over is the use of weed whip string which is used to smooth out the exterior of the bales before plaster is applied. With half a dozen string trimmers buzzing at the same time, a heck of a lot of micro-plastic flakes were being flung far and wide, polluting air, water and soil. Biochar is already being tested in 3D printing filament which looks very similar to trimmer string. No doubt there are different performance requirements, but surely binders exist that could produce strings with the relevant characteristics. Flinging out bits of biochar would undoubtably be better for flora and fauna.

New York has recently risen to the challenge of climate change legislation and is striving towards a zero carbon economy by 2050. The focus seems to be on eliminating operational carbon (i.e. fossil fuel used for energy production). However, we cannot ignore the carbon needed for creating buildings, infrastructure and transportation. Turning these into sinks instead of sources of high embodied carbon products is a challenge which brings with it enormous opportunity for creativity and job creation.

How Thermochemical Conversion can help New York address its Climate Goals

This week Cornell University hosted an excellent event focusing on the topic of how thermochemical conversion could help NYS reach the ambitious goals set forth in the recently passed Climate Leadership & Community Protection Act (CLCPA).  In short, the new law commits NY to meeting the carbon reduction goals suggested by the IPCC which are needed to keep warming to <2C. The law largely focuses on mitigation activities (e.g. 40% emission reductions by 2030; 85% reductions and net zero carbon by 2050), but also contains language supporting adaptation and climate resiliency initiatives.

It was pointed out that the law as currently written excludes pyrolysis, which was unfortunately lumped in with incineration under the ‘waste to energy’ label, from participating in the ‘alternative compliance mechanisms’ (ACM) which will be used to achieve net zero carbon in those situations where fossil fuels are not able to be completely eliminated (estimated at 15% of 1990 levels).  It should be noted however, that all electricity generation (presumably including solar, wind, etc.) are excluded from ACMs. Renewably generated power is already baked into the planned reductions, so allowing them to also serve as ACMs would, in effect, be double counting their carbon impact and would not truly get NYS to net zero carbon. It seems likely that renewable energy will be incentivized in other ways apart from the ACM.

Legislative heavy hitters that participated in a policy panel including Senator Jen Metzer, Chair of the NYS Ag Committee and her counterpart Assemblywoman Donna Lupardo pointed out that the focus at this stage should be on the essence of the bill and that changes are almost always made to broad legislation like this. They also noted that it was likely many of those that crafted, lobbied and voted on the bill may not understand the differences between incineration and pyrolysis nor know much about biochar. Fortunately (or not) the law provides a 2-year window for many voices across the state to be heard and for the details on how best to achieve these goals to be hammered out.

Of perhaps more interest, at least to me, in the language concerning acceptable ACMs are these 3 notes (under section 75-0109 4.g) indicating that ACMs must:

  1. Be designed to provide a discernable benefit to the environment rather than to be the source
  2. Be located in the same county, and within 25 linear miles, of the source of the emissions, to the extent practicable;
  3. Enhance the conditions of the ecosystem or geographic area adversely affected

There are several more provisions (all written as “or” statements versus “and” statements so who knows how the selection rating system will end up) but overall I find this promising news for the biochar industry (note that I’m focusing here on the biochar end product and not energy generation via thermochemical conversion). Item ‘i’ could potentially exclude technologies such as direct air capture and carbon sequestration (DACCS), a technology which seems to have no discernable environmental benefits beyond reducing emissions from smokestacks. Biochar on the other hand, provides a wide variety of environmental benefits, many of which also support climate change adaptation and resiliency in addition to long-term carbon storage.

The focus on local ACMs and enhancing ecosystems also play in biochar’s favor. Considering that NYS has ~1,700 large scale generators of organic waste (i.e. >2,000 lbs/week), much of which could be converted into biochar, locating closed-loop biochar production facilities across the state is certainly feasible. It will also help NYS meet the goals of the recently passed organics mandate. Dairy farmers could carbonize manure, using the heat for pasteurization – further reducing the need for fossil fuel energy – and use the biochar first for bedding, then manure management and finally as a soil amendment. Municipalities could convert mountains of green waste, using heat for local needs and biochar for storm water management.  These examples not only demonstrate that biochar solutions can be hyper local, they also enhance ecosystems.

Top 3 reasons for not calling biochar a fertilizer

Unlike biochar fertilizers come with one major upside and many downsides

Using the word fertilizer to describe man-made chemicals that are spread or sprayed on soils is perhaps the most unintended oxymoronic word choice ever, except for maybe plasticulture which I lamented long ago. While chemical fertilizers may help individual farmers realize short term crop yield increases, the long-term impacts to soil, air and water are overwhelmingly negative for those self-same farmers as well as many downstream flora, fauna and human folk.

Consider recent news that fertilizer production is responsible for belching out 100x more methane into the atmosphere than had been previously acknowledged. As CH4 is hugely more worrisome than CO2 from a warming perspective, this is a big deal. Or ponder perhaps the plight of polluted pools of water, starved of oxygen caused by leached fertilizer and manure. Fisher-folk around the world are now facing long-term unemployment because fertilizers have created dead zones, some as big as New Hampshire.

Chemical fertilizers are more akin to steroids which definitely boost short term performance but come with numerous unintended consequences. Perhaps a better name for them might be Ferticides when you consider their overall impact?

It is not uncommon for folks to talk about biochar as a fertilizer. However given all the negatives that come with fertilizers, perhaps we should refrain from equating it with these manmade soil steroids? Here are three reasons why biochar should be considered as something different from and, if I may suggest, better than fertilizer:

  1. Nutrient content: Many types of biochar do not in and of themselves contain nutrients that plants need. This is especially true of biochar made from woody materials. Many early research studies failed to recognize this, so yields were negatively impacted in the short term (which is unfortunately the length of time under study!) while biochar soaked up surrounding nutrients which were often released back to plants more slowly later on. While those early studies continue to be referenced as a reason not to use biochar, the biochar industry has long since learned that biochar should be combined with nutrients before soil application. Fortunately, there are many, many ways to do that with a wide variety of organic materials.
  2. Short-term vs long-term focus: fertilizer must be applied annually or even more frequently as it is subject to losses in the form of leaching, denitrification and volatilization. Biochar, on the other hand, is much longer lasting. Although flooding can move biochar from its original application location, it is still likely to persist wherever it ends up (unless it ends up in a fire!). While it is probably better to add biochar slowly so as not to shock the soil ecology, application of biochar is not needed indefinitely. After a few years of repeated application, soil organic matter content should reach levels that will promote long term fertility without the need for additional biochar.
  3. Singular focus vs multi-beneficial: Fertilizer companies emphasize the need for increased food production yet minimize the systemic negative impacts it has on the planet. This plays into our fears of food shortages, while downplaying the overwhelming negative externalities, a ploy also used by Big Oil, Big Pharma and others. Biochar combined with appropriate nutrients can provide a wide variety of benefits not only to soils, but in displacing fossil fuel derived energy, boosting photosynthesis and rebalancing atmospheric carbon.  

While there are additional reasons to refrain from referring to biochar as a fertilizer, these three provide fairly compelling reasons to find or invent some new vocabulary. Condilizer anyone?

The anti-dote for anti-biotic overload: biochar

Antibiotics, the wonder drug that has mended millions if not billions of us, may just be our undoing if we don’t act quickly to curb its contagion.  A recent article revealed that nearly 2/3 of rivers surveyed were tainted with antibiotics, some with levels 300 times what is considered safe. In the developed world drugs are excreted into toilets that flow into wastewater treatment plants that are ill-equipped to filter out what are known as ‘emerging contaminants of concern’, a term which doesn’t set off nearly the alarm bells that it should. The pathway for animals fed a steady diet of antibiotics to prevent disease and boost feed efficiency is even more direct: in one end and out the other of the animal (70 – 90% of what goes in, may come out!), and then into the soil and perhaps into groundwater. A brief sojourn in a manure lagoon may occur before soil application, but this is unlikely to fully degrade all of the various types of drugs. Lest you think anaerobic digestors are the answer, antibiotic laden manure can significantly reduce methane emissions in digesters yet there is concern that the antibiotics are not fully killed off during digestion.   Paradoxically it appears that antibiotics might boost methane emitted from cow paddies deposited in the field.

In addition to the methane madness caused by antibiotics, these superfluous drugs (by that I mean the 80% of anti-biotics that are fed to livestock for prophylactic reasons) are leading to super bugs and super strange looking fish. To clean up current contamination and prevent prospective pollution will require a multi-pronged strategy and some seriously smart money.  Biochar could be a major player in both alleviating existing issues and avoiding future problems.  Here’s how:

  1. Replace antibiotics in animal feed with biochar…at least with animals that are using them for better weight gain or preventing ailments. Though not yet legal everywhere, this one does the most to keep anti-biotics out of the environment and it also has cascading benefits such as improving soil carbon, reducing enteric emissions, etc.
  2. Carbonize livestock manure especially when animals are fed antibiotics. Many different types of antibiotics can be completely removed when pyrolyzed at 600C or higher. (Tien et al 2019) Ditto for human manure (aka sludge, biosolids). Not only does the heat kill off the contaminants, but manure and sludge volumes are reduced significantly which can help avert excess nutrient leaching into water bodies.
  3. Blend biochar with manure. This can either be done by adding it to bedding material or during composting. Biochar helps to degrade antibiotics and antibiotic resistant genes (ARGs) in manure. (Qian et al 2019) It will also help control odors and emissions while building long term soil carbon.
  4. In remote areas without access to wastewater treatment facilities, use biochar in composting toilets. Note that this biochar should not be used for growing food but could be fine for putting into biochar bricks. 
  5. Use specially designed biochar for removing antibiotics in wastewater treatment. (Chen et al 2019)
  6. Antibiotics abatement in soil: Apply biochar to soils contaminated with antibiotics to reduce leaching and bioavailability. (Liu et al 2018)
  7. In developing world areas that lack adequate drug disposal (e.g. health care clinics), dispose of unused or out of date antibiotics into metal barrels filled with biochar. These should be buried in safe areas not prone to flooding or leaching.

Raising Ambition: tangible climate action with biochar

The UN is hosting a Climate Action Summit in NYC in September with a catchy title of “A Race We Can Win”. One would hope that emphasizing optimism over the ever escalating doom will be a more effective motivator to shift quickly from planning to action!  The summit will highlight and promote the adoption of ambitious climate actions that will help countries to achieve their Nationally Determined Contributions (NDCs).  Using the 6 key areas they are focusing on, allow me to highlight a few examples that demonstrate how biochar can provide solutions within each area. 

Energy Transition: An increasing number of pyrolysis and gasification technologies are displacing heat or electricity formerly produced by fossil fuels. Pyreg, a German pyrolysis manufacturer has more than 2 dozen installations throughout Europe that are converting biomass into heat and biochar. Syncraft, an Austrian company that produces gasifiers for electricity production which can also produce high quality biochar in varying amounts to meet market demand, is expanding rapidly beyond Austria to Germany, Croatia and Japan.  

Climate Finance & Carbon Pricing: Carbon offset markets have traditionally locked out biochar for various reasons. Given that many of these markets are over-subscribed and undervalued, not being included in these marketplaces hasn’t really been a game changer for the biochar industry (though many in the industry might disagree with me).  The urgency for negative emissions technologies, highlighted in the IPCC’s Special Report, is spurring the development of carbon removal markets (perhaps we should call them Carbon Safety Deposit Banks?).  The number of products and/or projects capable of sequestering carbon is much smaller than the number of products that can offset fossil fuel emissions which obviously plays in biochar’s favor.  Removal marketplaces to keep an eye on include: Nori, Puro which just launched in Finland, and the Carbon Leasing Program being developed by European biochar producers that produce certified biochars.

Industry Transition: High emitting industries such as cement may be able to decarbonize using the heat from biochar production instead of using fossil fuels, as well as by adding biochar to cement to improve certain qualities and sequester carbon.  Displacing other high carbon ingredients such as carbon black, activated carbon made from coal, or graphite is another way to reduce emissions across many different industries (more on that in BURN: Using Fire to Cool the Earth).

Nature-based Solutions: As noted already, biochar production can be viewed as an offset for fossil fuel energy production. It also provides long term carbon storage which can benefit forests, agriculture (through improved soil fertility, water management, etc.), oceans (by reducing nutrient run-off which causes dead zones) and food systems (by immobilizing heavy metals in soils making food safer or by improving soils more food is produced).

Cities & Local Action: Urban infrastructure has paved over vast amounts of land leaving fewer safe places for heavy rain to go.  Using structured soils that combine biochar, compost and gravel can increase water drainage capacity substantially and reduce the impact of toxins that often result from flooding.  Cities such as Stockholm have been replacing heavy clay soils with specially designed structured soils to help reduce stormwater quantity and to filter out toxins. Other cities are beginning to follow their lead.

Resilience & Adaptation: Foresters are converting infected or dying trees into biochar and using the biochar to replant forests that have gone up in flames. Farmers are converting crop and livestock residues into biochar and blending it with other organic wastes which can reduce or eliminate the need for chemical fertilizers…which is better for their bottom line, better for their soils and better for rebalancing carbon…while seeing yields increase even during periods of drought.

The bright spots for biochar production and use are out there and multiplying quickly. I’ve endeavored to highlight some of them through this blog, through BURN (webinar on the book coming up on Friday, sign up here), through white papers (e.g. coffee cultivation & biochar) through biochar webinars and by organizing biochar study tours (join me on the next one in Finland Sept 4 – 6). What is needed now are detailed biochar scale up plans showing communities, countries and industries what technologies are already available to carbonize crops and decarbonize economies and how they can be implemented.  Done right, this not only helps meet NDCs but can create vibrant, resilient regional economies.

BURN: Using Fire to Cool the Earth by Albert Bates & Kathleen Draper

Fire, perhaps more than the other classical elements, can completely change all carbon-based materials. That transformation may sometimes be devastating but at other times it can be hugely beneficial. Most people tend to dwell on its wilder nature when it can voraciously consume forests along with any other flora and fauna in its path. It recently turned Paradise, CA into an inferno, leaving little life in its wake. But when tamed, fire has provided the means for humans to survive and thrive for millennia.

It hardly needs mentioning that we humans owe much to the transformational powers of burning or what is more technically referred to as combustion (an exothermic reaction which generates heat, light and a solid ash by-product). From converting raw meat into edible protein to converting heat into electricity to power countless conveniences; tamed fire has made life for humans significantly more palatable. We’ve learned how to tame fire with ever more sophistication over the centuries, enabling the production of more diverse and beneficial co-products while also taming many of the emissions that filled the skies with smoke and other nasty particulates.

Our burning techniques have progressed from simple campfires to sophisticated ovens; both use fire but the later is far easier to control and to use for creating mouth-watering masterpieces. This comparison highlights the difference between combustion and pyrolysis, a thermochemical process which decomposes organic material in an oxygen limited environment. (Some cooking ovens, in fact, are called pyrolytic ovens, but more commonly they are known as self-cleaning ovens!) There are a growing number of ways to achieve an oxygen limited environment, some sophisticated, some simple which indigenous cultures around the globe figured out centuries ago and created the now famous dark earth soils. While simpler technologies can produce high quality biochar, more sophisticated technologies can create and/or capture gases, liquids, heat or even electricity. When considered holistically our ability to tame fire and burn or bake all manner of underutilized organic materials, could be what keeps life on earth palatable moving forward.

In BURN: Using Fire to Cool the Earth (due out Feb 26), my co-author Albert Bates and I showcase the growing number of ways that tamed fire can be put to work to decarbonize households, products, industries and the planet. We outline how pyrolysis can help rebalance carbon by banking it instead of blowing it. We explore the burgeoning research showing how biochar’s benefits extend well above and beyond soils. We highlight how the ready-to-boom biochar industry is helping to store stable carbon in both consumable products such as cattle feed and kitty litter as well as durables such as asphalt and concrete. We hope that the perspectives provided in BURN will cause more companies to consider cashing in on caching carbon.

Hope you enjoy the book!

Biochar Bright Spots: Biochar Bricks

David Derbowka is one of my favorite kinds of charistas; creative, collaborative and cares about what matters most – a better climate future. David is an environmental engineer heading up his own company, PRSI, in a faraway place in Western Canada between Calgary and Vancouver. One of his areas of focus is phytoremediation of landfill leachate using fast growing poplar trees to soak up contaminants. Carbonizing these trees helps to reduce their bulk but some contaminants (e.g. metals) may remain ensconced within the carbon lattice.

Wanting to find a non-soil use for his biochar, David has been experimenting with using it in different materials such as bricks and drywall.  The samples he sent me many moons ago have traveled with me to all sorts of places including most recently to COP24 in Katowice, Poland.  I’ve told his brick story many times and plan to tell it many more times to come.  But now folks can hear about biochar bricks directly from David himself in this new youtube video.

Many folks enquire about recipes for using biochar in various building materials, wanting to save time and money leveraging what others have gleaned. For better or worse, many in the biochar world (and beyond!) are rather tight lipped when it comes to sharing this type of information, preferring to adhere to the capitalistic paradigm of prioritizing profits from patents. (This approach is a big part of what got us into our current carbon calamity.) David’s world view is the antithesis of that mode of thinking. As but one example, he recently shared his experiences openly and honestly with a group in South Africa that was looking to boost rural employment through green building materials.

These global, often times altruistic, collaborations are exciting to be a part of. They are what is needed to spread hope, knowledge and solutions far and wide. In this respect, I see David not only as a fellow pyrogenic lamplighter, but as one of biochar’s emerging ‘thousand points of light’ – an expression made popular by former President George H.W. Bush.  It was a modernized version of former President Kennedy’s “ask not what your country can do for you, but what you can do for your country”, which was a reinterpretation of the Three Muskateer’s (and the nation of Switzerland’s) motto: ‘all for one and one for all”. We need a XXI century version of this rallying cry (or maybe these days a meme would be more appropo!) that promotes a balance between taking and giving, between carbon spending and carbon banking, and perhaps hardest of all between profiting and planetary health.   

David’s recipe:


1 part Portland Cement

1 part water

3 parts biochar: note biochar should be soaked in water prior to mixing at a rate of 4 cups water to ½ cubic foot of biochar to reduce dust; particle size should be 1/8” or less.


  1. Mix water and Portland Cement together first
  2. Fold in three parts biochar.   A 1/2 inch electric drill makes this easier, but could be done with muscle power. If you find the mix too dry, add water, but very little, because it gets over wetted easily.  Too much water can slow curing and reduce compression strength.
  3. Pour biochar concrete mix into well oiled molds quickly after thorough mixing, returning a bit later to make perfect smooth finish.
  4. Once the product has hardened sufficiently (within 24 hours) cover with burlap soaked in water to keep it wet if possible.
  5. Wait 48 hours before emptying the molds or forms. 
  6. After removal, immerse bricks in water for two days.  During all moistening procedure, the char sucks up the water, and lets the portland finish curing
  7. Remove bricks and let them dry for ~ 27 days before using them.

NET Gestalt

Three NETs are better than one.
Reforestation, biochar & soil carbon sequestration can regenerate mine lands.

Every week more & more peer reviewed literature on biochar is published and 2019 will see the debut of a peer reviewed journal dedicated solely to biochar research. On average there are at least a dozen new papers each week making it impossible to stay on top of all the news coming out about biochar. Nevertheless, I persist! I confess that scanning new titles a few times per week has become a bit of an addiction. Most of the research is still behind paywalls, but a growing number of papers are open-sourced so the full report is downloadable. [If you’d like a monthly bibliography and good synopsis of the new research, consider becoming a member of IBI and you will get Bob Gillett’s monthly listing which also tells you which ones are free or behind a pay wall.]

The majority of the research is still heavily focused on agricultural uses but other topics are beginning to show up with more regularity. Filtration is big, remediating metals and other toxins in soils is also a frequent topic. Unfortunately, it is still not common to read biochar papers on its use in livestock feed and building materials (good recent exception here). [HINT: sometimes if you search for ‘nano-charcoal’ or ‘biocarbon’ you may find a few more.]

This week my favorite freebie comes out of Appalachia where researchers are testing biochar to help regrow forests on former coal mining lands. This particular paper jumped out as I just wrote about Negative Emissions Technologies (NETs) and how biochar can be used synergistically with two of the other NETs: afforestation/reforestation and soil carbon sequestration. When it comes to climate change solutions, we need less siloed thinking and more NET gestalt (meaning an organized whole that is perceived as more than the sum of its parts).  The Fields-Johnson et al (2018) paper highlights this very concept perfectly. Here is how…

Reforesting land that was stripped or blown apart in the careless crusade for fossil carbon is challenging both from a soil tilth and toxins perspective. Considering how much land has been pillaged for short term profit using surface mining, a whopping 1.2M hectares in Appalachia alone, being able to re-establish armies of CO2 sucking soldiers (aka trees) would be an absolute tour de force in our fight to rebalance carbon, not to mention a huge boost for biodiversity, flood control and economic development.

Researchers in West Virginia showed that biochar applied either in the root system or top dressed at varying rates for 2 different types of year-old sapling trees could potentially double above-ground biomass. Saplings grown in 100% biochar even doubled the below ground biomass as compared to mine soils.

Even though this was confined to pot trials using mine soil, this is really quite incredible when you consider the down stream implications. Getting fast growing native species to grow in contaminated soils could draw down an enormous amount of CO2. The rough math using 2,500 trees per ha and assuming 20 kg of CO2 absorbed per tree comes to 50 metric tons of CO2 per ha per year! Multiply that by 1.2M ha and Appalachia’s former mine lands could breathe in 60 Million metric tons of CO2. Now apply that to all the mine lands waiting to be resuscitated around the planet.

SOURCE: http://journal.reforestationchallenges.org/index.php/REFOR/article/view/91/73

But wait there is more. Soil carbon sequestration should also be considered.  The researchers applied biochar at three different rates: 2.3, 11.2 and 22.5 tons per hectare. The paper does not indicate the carbon content of the pine sawdust biochar but it is likely to be around 75% or more. At these rates the biochar could add 6.3, 30.8 and 61.9 tons of CO2e per hectare respectively. In Appalachia that would be 7.6M, 37M, or 74.3M tons of sequestered CO2e. The combination of photosynthesis and carbonization/sequestration could total more than 130M tons for the region!

Now imagine the Abandoned Mine funds set aside by coal companies being used to rebuild and rebalance carbon instead of adding insult to injury in the form of dumping fly ash or sewage sludge onto mine lands. Imagine carbon taxes on fossil fuel companies going towards rebuilding communities and eco-systems negatively impacted by drilling and desecrating landscapes. Combining reforestation, biochar & soil carbon sequestration to regenerate mine land is what I imagine an ideal NET gestalt looking like!

Safety NETs & Biochar

Humanity is in need of a safety net to pull us back from the carbon brink. But what might this net, or more likely nets, look like? The recent IPCC report may provide some clues.

The IPCC’s recent Special Report state’s that while steep and rapid emission reductions are critical, we have come to a point where carbon must be pro-actively pulled out of the air and stored safely elsewhere. Storage options are limited to land or oceans (though no doubt some would like a moonshot!). Land-based storage options include soils, deep geological storage or rocks – yes rocks!

The report lists a mere six negative emissions technologies (NET) that they feel may be capable of drawing down massive amounts of carbon. Biochar, for the first time is included in that shortlist. To recap the sequestration mechanism offered by biochar: carbonizing underutilized organic material, be it sewage sludge, city green waste, storm debris, invasive species, food waste or myriad other sources, converts recently photosynthesized atmospheric carbon into stable, long-lasting carbon that can be stored in soils or safely incorporated into man-made materials.

Biochar, along with only two other NETs, afforestation/reforestation and soil carbon sequestration are ancient, proven processes which provide many other benefits beyond sequestration. The other three NETs; Bioenergy with Carbon Capture & Storage (BECCS), Direct Air Capture with Carbon Storage (DACCS), and Enhanced Weathering, have yet to be proven scalable, and may come with unintended consequences and enormous cost.

A limiting factor for many of the proposed NETs is land. There is only so much bare land that can effectively be converted to forests, agricultural land that can store carbon without endangering food production or biodiversity, or remote lands that can safely store carbon captured from bioenergy production smoke stakes or pulled from thin air.

While the IPCC’s report lists soil (presumably agricultural) as biochar’s storage medium, this is not entirely accurate. Much of the earlier biochar research focused on agricultural uses in soils, but increasingly it is being shown that biochar can be put to good use in urban soils for storm water management and in contaminated soils (e.g. mine lands, brown fields, landfills etc.) thereby expanding the amount of land where biochar can be sequestered. Also, it is important to note, that biochar is increasingly being eyed as a material to put into various man-made materials as a means of displacing non-renewable, expensive or high carbon footprint materials. These products have productive lives above the soil before finding their way into the soil. This includes many shorter-lived products such as kitty litter, bio-plastics or filtration carbon which may end up in landfills where it still sequesters carbon and may even reduce methane emissions. Longer-lived biochar-based products are gaining attention in the form of building materials which not only serve as carbon sinks but can provide insulation for housing and other environmental benefits.

One other thing to note with biochar is that it can increase the sequestration potential of both afforestation/reforestation and soil carbon sequestration. When used to plant trees, biochar can not only speed up growth, but it has been shown to provide increased resistance against disease pressure, so trees may live longer. While developing healthy forests, thinning is a must, and this provides the fodder for biochar which can then be put back into forest soils helping to further boost soil fertility and water management while sequestering more carbon.

Soil carbon sequestration includes changing destructive agricultural practices such as tilling and also the incorporation of organic material into soils. Combining biochar with other relatively short-term carbon materials (e.g. manure, crop residue, compost, etc.) can not only provide longer-term carbon sequestration, it can help hold onto nutrients longer which reduces other negative environmental impacts such as groundwater contamination or eutrophication.

So as the need for carbon safety nets grows and our window of opportunity shrinks, let’s make sure we chose NETs that are in fact safe, sustainable and offer a high possibility of success. For a more in depth perspective of this topic, please have a read of this article on the Biochar Journal.

Biochar at COP24

Last week I attended the UNFCCC (COP24) in Katowice, Poland as an observer on behalf of the International Biochar Initiative (IBI). It was my first time attending and the first time in a long time for IBI. The intent was to both highlight biochar as a viable climate change tool and to evaluate the level of interest and knowledge about biochar amongst the attendees.

As a first-timer, the conference can be a bit overwhelming. The event draws more than twenty thousand attendees from around the globe (and its attending carbon footprint is barely acknowledged!). There are many different types of events going on simultaneously including opened and closed negotiating sessions,educational side events, national pavillion events, exhibits, press events, non-sanctioned events at nearby hotels and much, much more.

It is impossible to really get a comprehensive perspective of everything going on in just a few short days but I came away with the overall impression that there is far more talk than action going on. People are busy making pledges, quantifying baselines and emission sources, and planning ways to reduce and finance those reductions.  But when it comes to the hard work of actually cutting emissions, rebalancing atmospheric carbon and acclimating to our new climate reality, the pace seems heartbreakingly slow, the price tag excessively high, and the politics insurmountably grid-locked.

If I had to distill everything down to a few key messages that stood out for me they would be: 1) addressing the climate crisis must be done in collaboration with achieving the UN Sustainable Development Goals (which I have blogged about previously here), and 2) the focus for funding is equally divided between climate change adaptation and mitigation – and mitigation seems to be weighted more heavily on emissions reduction activities than on carbon drawdown at the moment.

While it would be disingenuous to claim that the messages coming out of such a conference were filled with hope, perhaps because I was there representing biochar, I still came away from the experience optimistic.  The optimism was surely not due to the popularity of biochar as very few people were even aware of its role in climate change mitigation or adaptation. Yet almost without exception when we were able to engage people in meaningful dialogue about the benefits of biochar production and use, there was broad interest in learning more and in bringing that knowledge to communities facing immediate, not future, impacts of our changing climate. 

At a meeting so focused on overwhelming problems, I think people were starved for solutions that are simple, scalable and shovel ready. Biochar, as I have said many times, is no silver bullet. But it definitely deserves a seat at the table when it comes to conferences such as this. However espousing the benefits of biochar needs to shift from a mere exhibit booth to being in front of the room where case studies and climate math can be discussed and used to inspire others to adopt and adapt. That’s my goal for next year’s conference! Ideas welcome for how to make that happen.