Dwelling on Drawdown Part III – C walls

Converting walls to carbon caches could be compelling when you consider just how much wall space there is in the average US home. Shifting from a high embodied carbon material such as drywall, to a carbon storing material could create a colossal carbon sink opportunity while also reducing current emissions from manufacturing materials such as drywall and making homes generally healthier at the same time.

The vast majority of inside walls in the US are covered using drywall (also called plaster board or wallboard), which is largely made from gypsum. The average American home, which is now close to 2,500 sf contains roughly 11,225sf of wall space.  A typical US home might therefore have 15,000+ lbs of drywall. The environmental impacts of mining, transporting and end of life for 15M tons of wallboard produced per year are enormous. Though it is recyclable, most of it heads to a landfill where it proceeds to off-gas sulfur dioxide, nitrous oxide (though this is also called laughing gas it is no laughing matter as it is a potent GHG), carbon monoxide and odors that you do not want to be smelling!

Covering walls with carbon storing materials is not new. Wood has long been used in many cultures, though it has fallen out of favor with many builders and homeowners. More recently we are seeing other carbon storage materials such as straw board or hemp begin to emerge.

One of the parameters for building my drawdown dwelling was to avoid drywall to the maximum extent possible and to utilize a variety of carbon storing materials instead. The exterior walls are built using straw bales – it took less than 2 acres roughly half a year to grow my walls – plus lumber of various flavors; dimensional, composite, etc. Interior walls (window sills and floors too) have been covered with rescued wood from barns and fences as well as locally and regionally harvested ash, cherry, maple and pine – a veritable forest or at least the ghosts thereof. All were sustainably harvested and putting them inside homes is a sure fired way to prevent the carbon absorbed during the tree’s lifetime from converting back into CO2 for as long as the house shall live!

As I am in the biochar world, I really wanted to have a biochar plaster wall similar to the one done at the Ithaka Institute headquarters in Switzerland. I procrastinated until all other interior walls were done which allowed me to get more comfortable with plastering in general. Now after two days of burnishing (i.e. rubbing walls gently with a mildly wet sponge to smooth lines, heal cracks and remove surface particles), the plaster is thankfully still on the wall and, all modesty aside, looks gorgeous (except for the tarps on the windows and the not completely finished window trim). Although originally I thought this was beyond my abilities, this is a project anyone can do but for those fastidious few, I warn you it is dirty to do (but pretty to view!).

Before taking the plunge, my co-conspirator and plaster master, Jill and I did some testing using different sized biochar, both of which came from Aries Clean Technology (Many Thanks Nancy at Aries!). Aries makes biochar from urban wood waste in Tennessee, and I knew they produce an IBI certified, very fine powdery size (2 – 300 microns) biochar that I’d wanted to test in plaster. They also had a chunkier size (<1/8”) which was worth exploring. Using the same recipe [50/30/20 v/v biochar, sand, clay] results in very different colors and textures which you can see in Figure 1.

Figure 1: On the left is the powdery biochar plaster which had a texture almost like frosting and on the right is much greyer and more like oatmeal.

The oatmeal version took quite a while longer to dry than the frosting.  In speaking with my colleague who pioneered this technique in Switzerland, he advised that the chunkier plaster can be used as a base coat to increase insulation and the finer biochar plaster makes a nice finish coat. Alas I already had a base coat, so decided to move along with the blacker finish coat. [For those that don’t fancy black walls, you can cover it using clay paint which comes in a variety of colors.]

We premeasured each ingredient and added them dry into a large bin before adding water. In hindsight, I would recommend wetting the biochar and/or clay beforehand to reduce dust while blending (kind of like slaking lime).  

We started with a 5 gallon bucket of Aries Green Tech powdery biochar, plus the requisite amount of sand and clay. We used roughly 3 gallons of water to get it into something just a bit heavier than frosting. This took quite a lot of time with a drill and paddle mixer to get to the right consistency and make sure everything was well blended. (If you are doing a bigger wall it would be easier to use a hydraulic mixer.)  I recommend doing this outside as there is a certain amount of splattering and in the beginning some of the particulate matter does get airborne. This ended up being not quite enough to cover a 80 – 90 square foot all, so we made up another smaller batch in a 5 gallon bucket.  

All in all, there is likely about 10 lbs of carbon (the Aries powdery char has 85% carbon) or about 36 lbs of CO2e; not a huge amount, but it was a very thin layer (1/8” – ¼”) and a pretty small wall!

Now let’s do some carbon math. Say this thin layer contains about .1 lb of carbon per sf (.367 lbs CO2e). That could easily be doubled or tripled as the average drywall width is 1/2″. Now imagine putting that on a majority of the 11,225sf of wall space in each home. Now multiply that by the nearly 1 million new homes built each year. That is big C storage opportunity with multiple side benefits. Those are the (C) walls we need to start building!

Side note: doing this type of project turns many a sponge and all clean up water very, very black. Knowing that the black comes from biochar means that tossing the black water out onto the soil or down the drain puts a guilt-free smile on my face knowing that it will enrich the soil and septic system!

2020 was not all doom, gloom & zoom for the US Biochar Industry

Good riddance 2020! Though I am not sad to see 2020 ride off into the history books, upon reflection there were a few highlights within the US Biochar Industry that should not go unacknowledged.  Here are a five worth celebrating as they may well help the biochar industry scale quickly in the year to come.

  1. An explosion of biochar related webinars! For many years I have hosted biochar webinars for the International Biochar Initiative to fill a void in biochar education. This year that void was filled to overflowing from many different organizations hosting a wide variety of biochar presentations, forums and continuing education credit opportunities. Most of these webinars or forums recorded the presentations which are now available for free. Several worth watching include:
  • The US Forest Service hosted a series of 8 webinars on a wide variety of topics including: what is it, production technologies, economics and several more. Mostly these were presented by US Forest Service employees that have been working with biochar for many years. (There were a few exceptions including one I gave on Innovative Products.)
  • The Scaling Biochar Forum, held in mid-October, was a 2 day event aimed at educating investors and philanthropists about the growing number of opportunities and funding needs within the biochar industry.
  • Cornell Cooperative Extension of Suffolk County hosted 4 webinars in November thanks to funding from SARE. Topics included: Biochar Basics, Science Behind Biochar, Ornamental Nursery Applications, and Landscape Applications of Biochar.
  • Thermochemical Conversion & Biochar workshop hosted virtually by the Rochester Institute of Technology was aimed at educating New York State policymakers, farmers, investors and more. The full recording is here and an overview of the event found here.
  • National Biochar Week – for 5 half days in December, biochar experts from around the country discussed many different applications and opportunities within the biochar industry. Recordings still being posted here.

2. First US producers receive carbon removal credits – the long awaited opportunity to tap into finance from the voluntary carbon markets arrived in 2020 for US biochar producers. Pacific Biochar was the first commercial biochar producer to profit from a collaboration with Carbon Future. Carbo Culture, a pre-commercial biochar producer also based in California has also been approved to sell carbon removal credits through Puro, the first carbon market to acknowledge biochar on a carbon marketplace.  Biochar credits are trading at significantly higher values than carbon offsets at least at this early stage. VERRA, a global leader in GHG reduction standards and methodologies, has also committed to developing and deploying a biochar GHG methodology in 2021.

3. USDA NRCS Soil Carbon Amendment Protocol (Code 808) – The USDA Natural Resource Conservation Service developed a protocol focused on increasing soil carbon specifically through the use of compost, biochar or a combination of the two. To date 20 States have adopted Code 808 and funding is apparently available up to $845 per acre for farms that have soil carbon issues. [Most of the information on this is only available in PDFs, so Google NRCS code 808 to find out more or visit your local County USDA to find out if your State is participating.]

4. Biochar allowed as a feed additive – but only in California so far! For years now the US Biochar industry has envied the European and other markets that have been able to sell high quality biochar as a livestock feed additive. Until quite recently that was not possible as the FDA had taken it off the approved list of feed amendments. In 2020 the California Department of Food & Agriculture approved the use of biochar (called charcoal in their regulations) in livestock feed. The Official California Code of Regulations for Food and Agriculture related to commercial feed states the following: (e) Charcoal (vegetable) is charred hard or soft wood, nut shells, or fruit pits. If it is wood charcoal, it shall bear a designation indicating whether it is hard wood charcoal or soft wood charcoal. Charcoal from nut shells or fruit pits shall be designated as shell charcoal. When used in a mixed feed the maximum percent shall be stated on the label. (Barclay’s Official California Code of Regulations)

5. Biochar Policy Task Force for the Biden Transition Team – As a majority of Americans (by at least 7M) breath a sigh of relief that the incoming administration understands, supports and ‘believes’ in science and climate change, the winds of policy change for the biochar industry began to formulate last month. The Biden Transition Team formed a bioenergy/biochar task force made up of a few biochar experts as well as policy wonks from many of the large US crop growers associations. They learned from various biochar academic and industry folk about the potential for US farmers and strategized about ways to help the industry scale quickly in 2021. Even just having this kind of dialogue signals a complete shift from the out-going administration.

One other anecdotal impact heard from various biochar industry players was that many folks around the world began to garden as a safe way to get out of the house and to feel more resilient. This created increased demand for the biochar industry in many parts of the world!

So, while 2020 seemed filled with doom, gloom and way too much Zoom, I hope you will agree that good things happened within the biochar world which laid a solid foundation for more to come in 2021.

Side note: I often use a picture of burned toast to describe the difference between torrefaction (regular toast) and pyrolysis (burned toast). It seems like a good visual to show why microbes prefer to leave it alone thereby allowing for long term sequestration versus decomposition.

From Wildcatter to Carbon Capper

Hopefully, for the sake of a livable planet, the days of wildcatting are nearly over. Prospectors drilling for oil and gas in regions not generally known to contain these materials came to be called wildcatters in the late 1800s. Prior to that a wildcat referred more generally to a risky venture. In retrospect wildcatters were gambling far more than their personal fortunes when they drilled hither and yon. Although to be fair, they could not have known that unearthing long dead plants to be burned as fuel could lead to catastrophic climate change.

What if there was a means of redemption for historical and current wildcatters? Perhaps those thousands or millions of wells, long since abandoned yet still able to wreak havoc below and above ground, could be converted into an ally in our urgent quest to rebalance atmospheric carbon. Perhaps wildcatters could become carbon cappers. Indulge me for a moment while I paint a picture perhaps with rose-colored glasses, and then feel free to join the conversation to figure out if this is even remotely possible, and if it is what is the potential for carbon sequestration, and how do we scale it in a time frame that makes a material difference.

Grist wrote an intriguing article earlier this month cheekily entitled Abandonment Issues. The gist of it is that carbon offset credits are beginning to be used to help finance the capping of old wells that are leaking methane, hydrogen sulfide and other toxins. Since many oil companies have declared bankruptcy to avoid covering clean-up costs, the bill is often left to taxpayers. Nowadays with Federal, State and Local government coffers severely depleted due to Covid, funding for this type of activity is challenging at best, even though it promises to provide needed jobs to unemployed oil & gas workers.

Non-producing wells seem to be categorized as abandoned, orphaned or idle. An estimated 3+ million of these wells in the US emitted 281 kilotons of CH4, a GHG far more potent than CO2. Currently a mere 50,000 are listed on State lists for clean up and even those will take years to properly close due to financial constraints. While a small minority may leak enough methane to cover the cost of capping the wells, the rest of the funds are currently being raised through donations or taxpayer dollars.

Typical materials used to cap wells include sand, gravel, native clay, sodium bentonite and cement (note: cement comes with a high carbon footprint which should be factored into the overall life cycle assessment for carbon offsets and removals). Now imagine if instead of sand or clay or cement, biochar could be used to displace some portion of these imported materials.

Apparently some of these wells, at least in my part of the world, are thousands of feet deep so could potentially sequester vast amounts of solid carbon in the form of biochar. While the volumes for filling smaller holes might not be large enough to raise sufficient carbon removal funds to cover the entire cost of capping, biochar could also be used to remediate nearby contaminated soil and water. It might also be better at sorbing hydrogen sulfine, benzene or other toxins than sand or clay.

One thing to note is that while revenues related to carbon offsets are still languishing at an average of $10/t of CO2e, carbon removal credits are currently garnering far higher prices. Though biochar has only recently debuted on 2 carbon removal marketplaces (Puro.earth and carbonfuture.earth), it is poised to become part of much larger marketplaces as VERRA, the world’s largest standards registry, just announced it is developing a biochar GHG methodology to be finalized by the end of 2021. Prices per ton of CO2e for biochar have ranged from $75 – 145 so far. Converting that back into dry tons of biochar generates $200 – $350 meaning the price of biochar could become cost competitive with other fill material if it is locally produced from waste material. To state that differently, for every ton of biochar used, between 2.5 – 3.0 tons of CO2e credits can be sold. (The multiplier depends on various things including emissions related to feedstock acquisition & transportation, processing emissions, carbon content within the biochar, etc.)

With insufficient experience in calculating the volume of materials needed for different sized wells as well as average land area needed to remediate, it is hard to calculate how much carbon removal revenues could be generated. But any additional revenues would no doubt be welcomed to plug these toxic legacy wells. I invite those that know far more than I do on this topic to discuss and hopefully demonstrate feasibility.

Dwelling on Drawdown – Draining the Swamp

For the past several months I have been building my ‘Dwelling on Drawdown’ forever home. As the project name implies, a key emphasis is on sequestering carbon in as many ways as possible. So far biochar has not been the center of attention, but this week that changed as my septic system began to take shape.

First some background. On a freezing cold day last January when the civil engineer, accompanied by the local lake water quality control agent, performed a perc test to see how quickly water drains, the results were (unsurprisingly) not good. In my part of the world heavy clay soils are the norm. During the test, I (also unsurprisingly) waxed poetic about the potential benefits of adding biochar to the leach field – or drain field as it is also called. This was met with more than a little skepticism (and I suspect some eye rolling). However, much to his credit, when the civil engineer sent me the final design for the raised bed system, he outlined how biochar could be utilized effectively without raising regulatory concerns. Seemed like he may have read up on biochar after our little conversation!

Fast forward to the need to source sufficient amounts of biochar for draining the swamp, er… septic system.  What type of biochar is best? I don’t know if there is consensus on that as this might just be the first time it has been used in a residential drain field. There is no large-scale biochar production yet in Western New York and I’d already used up my own home-made supply in the water trench. I ended up ordering 6 super sacks from National Carbon Technologies (thanks to Cary Johnson!). NCT is probably one of the largest producers of ‘renewable carbon’ in the United States. Some of the carbon is used in carbon neutral markets but increasingly they are looking at carbon negative markets such as soil amendments. The biochar is made from sustainably sourced wood with high carbon content (>90%) and can be granular or pulverized – I chose granular.

Thankfully, the excavator (Schwartz Excavation) is a family friend and was game to try out the use of biochar. Eight truckloads of sand, mined about 20 miles away, were brought in to raise up the entire drain field. Next a trench was built for a distribution box to send out the effluent into 5 different trenches about 60’L x 2’W x2 1/3’D. The Civil Engineer advised digging deeper trenches and then first adding a layer of biochar to the subsoil. This meant that instead of digging only 2’ deep, trenches were 4” deeper to accommodate the biochar. Super sacks turned out to be the ideal packaging for adding biochar to trenches; it was no fuss, no muss and surprisingly little to no dust during the application. Randy, the excavator, declared that the biochar was too pretty to cover up after the first trench was filled. But cover it they did; first with 6” gravel, then they laid in the perforated pipe, 6” more gravel was added to cover the pipe, next a geotextile was used to cover the gravel to prevent soil from clogging the gravel and finally 12” of topsoil.

In total three super sacks were used or roughly 1 ton for the whole system. The carbon math on that means that nearly 3 tons of CO2e were sequestered in the drain field.

Why add biochar to a drain field? While I think most drain fields could benefit from biochar, living next to a lake makes reduction of excess nutrients and contaminants particularly important. Biochar will also likely help with water management. Given my druthers, I would have mixed the sand with significant amounts of biochar to reduce trucking, improve water management and boost soil fertility, but that will require more study and education of regulators. It might not be cost effective to do that at this stage, though with carbon removal credits beginning to evolve for biochar, that may soon change the economics significantly.

Wouldn’t it be something to design drain fields that are built to serve not only as filtration devices but could purposely be used as soil builders where enriched biochar is harvested every decade or two and used to rejuvenate or decontaminate poor soils and new biochar is added to start the process all over again? Hopefully some environmentally woke civil engineers are already hard at work on this!

Biochar in the time of Coronavirus

I have lost count of the number of people that have asked if or how biochar might be able to help when it comes to our current pandemic. Years ago I wrote about how biochar might be able to help prevent the spread of cholera, looking mostly at a post disaster scenario where this bacterial disease can often become commonplace. Containing a virus that has gone global is a totally different tragedy. Nevertheless, there are still ways that biochar may be able to help.

Masks made with biochar: Activated carbon has long been used in personal protective gear (PPE) and there is some indication that certain types of carbon may be effective in inactivated viruses (Matsushita et al 2013). Robert Tonks has pioneered a truly innovative, reusable mask (pictured above) that contains biochar which could be made in mobile manufacturing facilities. 

Carbonizing contaminated medical waste: At the moment, vast amounts of PPE are being used and discarded at an ever-increasing rate. Presumably much of this will be incinerated at least in those parts of the world where incineration is available. Carbonization might be a viable option however, at least for the paper-based PPE. The high heat temperatures should eliminate the virus and the resulting biochar could be used for a variety of purposes including potentially masks!

Carbonizing human feces: There is some indication that human feces may contain traces of the virus though more research is needed to understand if the virus can be spread from it.  To be on the safe side, putting sludge through a thermochemical conversion system would eliminate that risk – and provide substantial other benefits as well.

Carbonization vs. cremation: funeral homes are overloaded in hot spot zones for the pandemic. Though the concept of carbonizing human remains is still largely theoretical, it is feasible.  Keeping part of a loved-one’s carbon from returning to the atmosphere might seem like purgatory to some, but it might be one small way to help rebalance carbon levels!

Perhaps the most interesting take I’ve heard about how biochar can help during this pandemic has to do with stalled international deliveries of things like fertilizer.  Farmers in the Northern Hemisphere are just about ready to start planting and going without fertilizer is causing many to panic.  However, those that know how to convert biomass to biochar and blend it with locally available nutrients (e.g. manure, urine, compost, etc.) can wean themselves off their dependency on imported fertilizer. This not only increases their resiliency but also reduces costs and emissions related to fertilizer use It can also alleviate leaching of excess nutrients into local water bodies.

Sensitizing the sanitation community to sequestration (and biochar!)

I was recently asked by the NYC Department of Sanitation to keynote at their SOAR Strategic Partnership Breakfast which was also highlighting International Women’s Day. It was a great opportunity to enlighten urban sanitation folks about biochar. With a few edits, here is my talk (warning – longer than most of my blog posts but hopefully it will be of interest).

It’s been far too long since I roamed the streets of NYC as one who called it home, but the invitation to return and hear about what is going on in the world of waste, or as I prefer to call it, unloved organics, was more than a little appealing. When I last lived here my career was about as far away from reimaging or repurposing organics as it is possible to get. I did a mid-life career 180 after going back to complete a Masters in Sustainability about a decade ago. It was during that time that I read about a little something called biochar which changed the entire course of my life! At the time I had no idea how few people had ever heard of it, nor did I think that 10 years later, roughly 98% of anyone I’ve ever talked to about biochar would respond with ‘bio-what’. But over the last year or so, things have really started to change rapidly on so many different fronts within the industry, that I am convinced the future for biochar is bright. So if you had never heard of biochar before getting your invitation to this event, know that you are in the vast majority, but please allow me to enlighten you just a bit about this exciting and diverse material and the process by which it is made.

Biochar is a fancy new name for a material born from an ancient indigenous waste management practice – most likely devised by women in my humble opinion – since it centered around cooking. The process seems astonishingly simple in retrospect yet had profoundly positive and long-lasting impacts.  As you might imagine cooking in fire pits produces prodigious amounts of hot coals. It appears that human urine and probably other ‘leftovers’, were dumped on top of the burning coals in an effort to both reduce odors from urine and feces and to thoroughly quench the fires. Whether by accident or design this combination eventually converted crappy soils – that’s not the technical term but I grew up on a farm and that is how you usually hear low fertility soils described – into highly productive soils capable of feeding a population far greater than had been previously imagined. Fast forward a few millenia and those same soils are still up to 4x more fertile than surrounding soils in the Amazon which were untouched by human hands. In fact, those same soils are being dug up and sold to boost soil fertility elsewhere.

Late last century these highly fertile soils were re-discovered and piqued the interest of soil scientists and archeologists.  More recently the biochar industry has garned interest from a much more diverse flock such as waste managers, urban planners, the construction industry and climate change scientists and activists.  The reason for this diverse interest is that the production and use of biochar brings with it a range of benefits. Those of interest to this gathering include:

  • Volume reduction – depending on the temperatures used and the organic material volume can be reduced by 70 – 95%!
  • Speed – compared to other organic management practices, the use of high heat and low oxygen, what we refer to in the industry as thermo-chemical conversion or TCC can be done in minutes or hours versus weeks. Thermochemical conversion includes technologies such as pyrolysis and gasification, but it should not be confused with incineration. Think of it more like baking; you put something in the oven, close the door and crank up the heat. If you are anything like me, sometimes you get something that is not at all appetizing, but it is my favorite color – black! This unappealing taste may be why soil microbes and decomposers don’t like to consume it allowing carbon to persists in soils for millennia.
  • Odor & pathogen control – TCC can also significantly reduce and in many cases eliminate odors and pathogens both directly and indirectly – meaning when added to landfills, compost piles or manure slurries, it can bind or hug toxins to prevent them from leaching and do the same with ammonia which causes the all too-familiar smell of ‘eau de landfill’.
  • Scalability – technologies for converting organics to biochar range from backyard kilns capable of carbonizing tree debris, to community scale, to multi-million dollar production facilities.
  • Renewable energy – some TCC technologies can harvest the heat generated from baking the organic matter. This heat can either be used for drying wetter material or can be used for other heating needs.  Other equipment produces syngas which can be used to generate electricity while still others produce bio-oil which can be refined to be used as a fuel.
  • And finally, there is the carbon impact. Organics sent to landfills or even to compost facilities can emit significant GHGs. While carbonizing organics with high heat and low oxygen does produce some GHGs, when managed properly TCC is considered a negative emission technology (or NET), meaning the overall impact is that more carbon will be prevented from returning to the atmosphere than is emitted. Think of it as carbon interruptus.  This is something the IPCC and others have said is critical to avoiding climate chaos.

We are seeing more requirements to reduce and neutralize emissions at least in NY, if not at a national level. Given that, shifting from a carbon belching process to a carbon banking one, may be well worth considering.  And though the carbon markets in the US don’t yet recognize biochar production and use as a product category, that is one of the areas that is starting to change very quickly. I predict we will start to see increasing revenues focused on carbon removal (e.g. NETs) versus carbon reductions (i.e. from renewable energy generation). Biochar is likely to be a key component of carbon removal markets.

A growing number of closed loop biochar production scenarios are sprouting up across the globe. Here are just a smattering.

  • One of the oldest can be found in Austria where a compost company, Sonnenerde, began accepting paper mill waste and turning it into biochar which was then blended with different compost recipes.  Adding biochar to compost can not only reduce odors and pathogens as I mentioned, but it can boost temperatures, speed up the processing time, hold on to more nutrients, serve as a bulking agent and provide longer lasting carbon to the soil.
  • One of the most talked about models hails from Stockholm where the city converts green waste from residents and city Parks into heat that is fed into a district heating system and biochar.  Their first demo plant was launched as a way to reduce the amount of biochar they imported from other countries which they had been using to improve urban tree survival.  An unanticipated benefit they discovered as they began to use more and more structured soil made up of gravel, compost & biochar is that the amount of rainwater that could be stored during storms increased significantly while the amount of toxins from roads and roofs that had to be dealt with at the waste water treatment plant decreased. These toxins were bound in the biochar. City officials took notice and now this model is being replicated not only across Sweden and Europe, but here in the US as well where I believe Minneapolis is the first large city to be planning a pyrolysis plant.
  • More recently an Australian company, Rainbow Bee Eater, located a carbonizer in an enormous 2 acre greenhouse to provide renewable energy. The fuel for the carbonizer is wood supplied by a local composter who provides it for free in exchange for taking the biochar produced from the machine which is added back to their compost.
  • Closer to home is an enormous gasification plant being built in New Jersey by Aries Clean Energy. They plan to convert 440 tons per day of sewage sludge into 22 tons per day of char. A long-term offtake agreement has been signed with a local cement company that will be using it as a filler instead of fly-ash, a by-product from coal fired electricity generation plants. In the past decade alone roughly half of the coal generating capacity has been shuttered so cement manufacturers are on the look-out for new alternatives.  
  • East of here, out on Long Island, 2 projects are being investigated aimed at carbonizing mountains of wood chips which are leaching heavy metals into the groundwater.  The goal for at least some of the biochar to be produced is to use it in bio-filters across the island to reduce the amount of nutrients, phosphorus mostly, leaching from hundreds of thousands of septic systems into local water bodies causing massive algae blooms and die off of various native aquatic species.
  • And in Western NY where I live Cornell University in collaboration with NYSERDA is looking at siting the first pyrolysis plant on a dairy farm to deal with excess manure. Amongst other end uses for dairy manure biochar, we will be looking to use it to filter the wastewater from dairy production or possibly the effluents from nearby food processing companies such as yogurt or tofu manufacturing. Using biochar in this way harvests the nutrients and allows them to be cycled back into the soil for use by plants. We dubbed this kind of beneficial carbon cascade the ‘filtration to fertilizer’ approach
  • I’ve also been working with the Rochester Institute of Technology for the past several years on converting different types of food waste into biochar. Biochar made from mixed food waste may have a lot of salt or chlorine, so using it in soils may not be the best solution. Instead we’ve been looking at using it in different types of composites. I have a prototype here which is a non-plastic, compostable tray made using 20% coffee waste biochar. One could call it biodegradable but I don’t love the term biodegradable due to the negative connotations of the word ‘degrade’. Instead I prefer bioUPgradable, since biochar-based products will sequester carbon and not produce GHG emissions whether you compost it or toss it in the landfill.

Low or variable quality biochar from mixed food waste or sewage sludge is also being tested in asphalt while higher quality and more consistent biochar is starting to be used in building materials such as flooring, composite lumber, and exterior siding. This will hopefully encourage the construction industry to build vast new above-ground carbon sinks.

SUPPORT NY LEGISLATIVE GOALS

There are a growing number of ways biochar can help New York achieve some of the ambitious legislation that has been passed in the past year or so.  The Organics Mandate prohibiting large scale food waste from being sent to landfills is one example.  Providing additional ways to deal with food waste such as TCC, could support broader adoption.  Co-locating pyrolysis with composting operations or anaerobic digesters may make a lot of sense.

I’ve mentioned the boost to compost that adding biochar can make but there are also synergies with anaerobic digestion as well. One issue some AD operators have is managing the excess fiber or digestate.  Digestate can be used as a feedstock for biochar and help reduce volumes.  The resulting digestate biochar can be fed into the digester as a carbon source. Research has shown that this can improve the quantity and quality of methane produced making the economics of operating a biogas plant more attractive. Biochar also seems to provide a kind of buffer which helps smooths out production ups and downs which occur when the substrate mix is changed. Adding biochar can also reduce the amount of hydrogen sulfide produced which can be harsh on equipment, reducing its operating life.

Biochar can help New York achieve the aggressive yet vital goals that were set forth last year in the Climate Leadership and Community Protection Act.  That legislation committed NY to a goal of 85% reduction by 2050 with all sectors being net zero emissions by then as well. To reach net zero, those that cannot completely eliminate all emissions must offset any remaining emissions through projects that permanently remove GHG from the atmosphere. What is new and I think important that NY has done with this legislation is that they will not allow renewable energy to be used as an offset as that is already baked into the reduction goals.  There are not that many ways to permanently remove GHGs from the atmosphere. Trees can do an excellent job pulling CO2 from the atmosphere, but as we’ve seen out West and Down Under, those trees are increasingly at risk of going up in smoke and giving back all the CO2 they absorbed during their lifetime.

According to the IPCC biochar is one of only 6 technologies touted as being able to make a material difference in rebalancing atmospheric carbon levels. Half of the other suggested technologies have yet to be proven economical viable or environmentally benign. In comparison biochar production and use is safe, scalable and shovel ready. It provides multiple benefits above and beyond the ability to help mitigate and adapt to climate change as I’ve already described.  

So with all this good news, why haven’t more people heard of biochar and why haven’t more communities adopted this kind of waste management approach? That is a question I get asked A LOT. In fact, I ask myself this question all the time.

A few years ago, the lack of biochar adoption could have been blamed on the lack of sufficient time-tested equipment or, importantly, local technical support available to make a good quality, consistent biochar. That has begun to change.   

One of the reasons I believe biochar has so far struggled is that the primary market targeted over the past decade has been agriculture. In the early days of any new industry when production is low and prices are high, going after a market that is already very low margin and high risk is probably not the best first step. Until or unless farmers start getting paid to build soil carbon their focus must, of necessity, be on the lowest cost means of production and right now biochar is too expensive for many annual crops when you compare it to cheap chemical fertilizers

Over the past few years though the industry has begun to expand their market focus beyond soil applications. Nowadays we are looking at less seasonal and more repeatable markets such as filtration where it can compete cost effectively against activated carbon, or in plastics and other composites where it can displace carbon black, a high cost fossil fuel product used in everything from back plastic bags to tires. It’s even finding its way into batteries. Those higher value markets will enable production to scale which will enable prices to fall which will hopefully then make it more economically feasible for most farmers to use it.

As with every young industry, we have seen companies enter and fold, we have had our fair share of snake oil salesmen and those hoping to quickly cash in on a perceived gold-rush – mind you many of those are the ones that have already departed, thankfully. Right now we are seeing an unprecedented level of interest from impact investors, carbon brokers, communities choking on waste, foresters desperate to remove excess biomass and of course many who are beginning to panic when it comes to climate change.

We are thrilled at all the new interest but those of us that have been in the industry for years understand and want to make sure that others understand that biochar is not a silver bullet nor is it like the Field of Dreams where you can expect to have unlimited demand once you start making biochar. To make the economics work and to maximize the carbon impact, it is critical to create biochar production scenarios that embrace the circular economy, that utilize all possible co-products including heat, and to build local markets instead of shipping biochar half way around the world – something which is happening far too frequently. Waste managers are uniquely poised to help build this industry but my advice would be to partner with someone that knows biochar well before you dive it. There are as many different kinds of biochar as there are different kinds of biomass; more really since different production parameters generate different qualities in biochar. Each of these types of biochar may be good for different markets and therefore the expected price for it will differ.

With that said, I welcome each and everyone of you to learn more about biochar. We need to scale this industry quickly and efficiently. 

If you are interested in learning more about biochar, the Rochester Institute of Technology will be hosting a free one-day thermo-chemical conversion and biochar workshop on April 20th up in Rochester. All are invited though registration is limited and required.

I also need to give a shameless plug for a book I co-authored last year called BURN: Using Fire to Cool the Earth.  In this book we explore many of the markets I’ve mentioned today and more. 

Many thanks for listening (well reading in this case!) and Charpe Diem!

5 Stages of Falling in Love with Biochar

Perhaps it is because of the ominous stage of the climate crisis and the understandable desire to rescue civilization from an increasingly dire future. Or perhaps it is because of more mundane motivators such as reducing organics sent to landfills, generating clean, renewable energy or reducing air pollution. Regardless of the reason, the biochar industry is witnessing a significant increase in interest over the past year. More and more individuals, companies, cities and other entities are discovering the oft overlooked carbon rebalancer known as biochar.

Needless to say, all of this newfound interest is welcome news for those of us that have been struggling to birth the industry for years. Perhaps unsurprisingly many of the ‘oldtimers’ are now being approached by untold newcomers with questions about biochar, markets, technologies, policies, barriers, standards, and the list goes on. Almost all want easy answers to which I often think to myself “if it were easy, the industry would be built already’.

A curious pattern seems to be emerging for those newly ‘biocharmed’ as I like to call them. In contrast to the five stages of grief (denial, anger, bargaining, depression, acceptance), which could easily be applied to the increasing number of people suffering from eco-anxiety, I’d like to suggest the five soul soothing stages of falling in love with biochar (which could be applied to other safe, scalable and shovel-ready strategies to combat climate chaos). It should be noted that these stages may be cumulative versus linear for some of us. Here is a closer look:

Stage 1: Hopeful

When most people first learn about biochar, and I definitely include myself in this, the reaction is often a mixture of hope, relief and skepticism (perhaps a new portmanteau for this sentiment could be ‘horesk’?). Learning that there is an existing, cost-effective, scalable technology that can materially help rebalance carbon seems almost too good to be true. Many wonder why this isn’t better known and why it isn’t being rolled out en masse if it is so promising. Those of us in the industry often ponder this point as well, but we have a better understanding of the barriers.

Stage 2: Exuberant

Once the initial ‘aha’ stage begins to pass, the ‘yee-ha’ stage takes over. There is usually a lot of learning happening during this stage, but people get very switched on to all things biochar, which often leads them to quickly move on to the next stage.

Stage 3: Evangelism

“Charvangelists” come in all stripes, though the predominant geography seems to be from North America. At this stage the newly biocharmed are telling everyone who will listen, and many who can’t seem to be bothered, about just how great biochar is, often ad nauseum (just ask my family as they have subjected to this for years). Individuals in stage 3 are fearless and forthright. They speak to people they might never imaged speaking to before biochar entered their lives: farmers, foresters, and foes across the political aisle. They reach out to schools, churches, master gardeners and frankly anyone they think might listen and make a difference (I know from whence I speak!). Many people linger in this stage or may bring their charvangelism with them to the next stage.

Stage 4: Overwhelmed

In order for biochar (or any other quiver in the climate change solution set) to make a material impact on climate change, it must scale, and scale quickly. All new industries are challenged by scaling but doing so under the uncompromising time constraints of the global carbon budget makes scaling in the Anthropocene a Herculean task. The current Western culture seems ill equipped to turn multitudes of mere mortals into Carbon conquerors, which is perhaps why this stage can feel daunting in the extreme.

As those in the industry know, production of biochar is no longer the constraint to scaling. There is a lot of biochar production capability and interest just waiting for a market before they invest in infrastructure. Where to utilize the vast amounts of biochar that can and will be produced in the most beneficial and economical manner is the real hurdle. Identifying, creating and scaling those markets is nothing short of overwhelming.

Stage 5: Focused

Getting focused is the key to sustainable progress in many if not most situations. Understanding the biochar industry from soup to nuts is challenging but critical. It is important to understand how biochar is made, the different co-products that can be generated with different technologies and what their value may be in different geographies and industries; the variability of biochar and how to design them for specific end uses; the standards and policies that help or hinder different biochar markets; the climate change impact; and the emerging impact of carbon removal markets.

The sooner those new to biochar are able to focus on a few key biochar aspects and/or markets in their region or in their area of expertise, the sooner we will start to see substantial and sustainable scaling.

Biochar: Crossing the “Finnish” Line

Last week I hosted roughly 120 people for the latest biochar study tour in Finland. We had participants from 18 different countries, from students to CEOs, from the biochar litterati to those very new to the topic, from academia to those braving up to the task of commercialization. We had more than 2 dozen speakers that spoke about carbon markets, biochar building materials (always a hot topic), carbonizing sewage sludge, activating carbon, the potential of wood vinegar, production technologies and much, much more. It was as invigorating as the Finn’s penchant for “avanto” (ice swimming) – something that we didn’t manage to squeeze on to the agenda!

This was the 4th tour that I’ve organized and each one seems to get better and bigger than the previous one. Tours are meant to highlight biochar ‘bright spots’ and encourage people from around the world to replicate models that are economically and environmentally viable. They are also meant to bring together those looking to share, connect and learn with and from others in the biochar world. I have no doubt friendships were formed, alliances arranged, and new business ventures were born…or at least penciled out over a Finnish beer or three.

The format may be more casual than many conferences which is perhaps why I prefer the term ‘study tour’. Though we had some of the top European biochar ‘rock stars’ they mingled easily and eagerly with everyone present. It was a rare but important occasion for academics to consort with commercial biochar professionals which encouraged cross-pollination of theories and thoughts on future research and markets. We had ‘open mic’ on our 2 hour bus ride from Helsinki to Tampere where those that weren’t already listed as speakers during the event could tell their biochar story. This enabled people to connect more quickly with like-minded individuals during the tour.

Our technology host was Carbofex OY, a company which has been running a pilot scale pyrolysis unit in Tampere for quite some time. Sampo Turkiainen, the CEO, could not have provided a better example of how to encourage sustainable production while also keenly aware of the need to build markets if the biochar industry is to scale quickly. We toured not only the Carbofex factory but one of their nearby projects where biochar is being used in a leachate remediation project from a former pulp and papermill landfill.

I was fortunate to have a team of 4 talented, hard-working and fun Finns to help put this tour together most of whom I did not know well before we started this journey. They helped significantly when it came to choosing engaging and enlightened speakers from Finland. It is truly inspiring to see so much biochar activity, both commercial and academic, coming from a country that has a tiny population of 5.5 million. It really makes one consider how this country, and a few other small countries (e.g. Sweden, Austria, Switzerland) are able to gain traction and move things forward better than other countries. Perhaps we all need to consider avanto to help us rise to the challenge of fending off climate chaos?

To casually throw one’s body into freezing waters is to begin to understand the Finnish word sisu—which means courageously pushing yourself beyond your self-imposed mental and physical limits.

Lola Akinmade Åkerström

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.