Off Grid Power in Liberia 

End of Year Update

December 2022

2022 has been a year of reemergence for APL. After two years where our markets and customer projects largely stopped due to the pandemic, we’re happy to see your projects starting again, and a similar return to near full activity across APL departments. We’re also simply pleased to still be here after a decade+—despite a few bumps and bruises—but moreso with vastly advanced machines vs a decade ago, and incredible memories of all the people we’ve met around the world, during this ongoing story of taming gasification for general use and global impact.

All of us have been outliers in this work for years; but finally our era of climate wilding, fossil fuel replacement, and transition to regenerative and circular stewardship, has moved our solutions to center stage. The climate clock tells us we have just nine years left before hitting 1.5°C of global heating, and looking in just about any direction finds some system in a critical state and threatening to bite.  It is now prime time for the solutions we’ve long been preparing.

APL began this journey with the broad notion of creating “mechabolic” machines which participate in the carbon cycle in a bio-imitative manner, while adding human value outputs along the way. Waste organic matter has proven a tremendous resource and place to center mechabolic engagements.  Byproduct biomass is captured carbon and stored solar energy, often with a whole range of minerals and microbes along for the ride and ready to do useful work, beyond generating electricity. Every year APL expands further into these native resource potentials of biomass, transforming them into useful power and products, while drawing down carbon and regenerating soil in the process.

carbon market graphs

This year we saw the Carbon Credits Markets finally grow into a strong financial signal for the carbon management outcome of this work. The carbon credit line item in a project proforma can now be as large as the electricity or biochar sale line items. Similarly, public funding to accelerate deployment of these solutions is expanding on all fronts, from local city efforts to national and international mega programs.

The work of our era is not just to invent, but more importantly deploy at scale the equipment and projects that make these transition solutions reality. All the pieces are in place for a big 2023 and beyond for APL solutions and your ability to access them with new financial rewards.

End of Year Deposits for 2023 Shipments

We are currently planning for 2023 deliveries and realistically there is a limit to just how many Power Pallets we can deliver considering the rise in interest and ongoing supply chain challenges. So if you’ve been on the fence about purchasing equipment, you’re encouraged to  place a $10k fully refundable deposit and book your spot in the production queue. Booking these orders will also help us negotiate better price and delivery terms with our various supply chain partners. 

Power Pallet

We’ve focused on product reliability and implemented changes on the Power Pallet (PP30 v2.0), including a new coolant draining and filling process, new gasketing materials, and updating the design of the filter heat exchanger (PG HX) cleaning mechanism. 

PP30 three quarter view

We’ve focused on product reliability and implemented changes on the Power Pallet (PP30 v2.0), including a new coolant draining and filling process, new gasketing materials, and updating the design of the filter heat exchanger (PG HX) cleaning mechanism. 

With support from the California Energy Commissions we also completed more work on our Containerized Biomass Microgrid system where we integrate two Power Pallets with other balance of systems components such as a feedstock conveyor and electrical components such as Level 2 EV charging capability in a 20” container. The first units will be deployed to Green Waste Recycle Yard in Richmond, California in 2023. The CBM system will only be available in North America until such time we have OEM and Licensing partners in other regions.

PP50 rendering


We are very excited about our Chartainer product which we are developing to meet customer requests in forestry agriculture and urban communities for systems that can process woodwaste at a higher rate. This combined heat and biochar system has an expected half ton/hr biomass input capacity and 20% biochar conversion rate. Please fill in this form if you are interested in the system.

SkyCarbon Biochar

Very pleased to inform everyone that the most recent biochar produced from wood chips by our Power Pallet and CharTainer systems has been certified by the International Biochar Initiative (IBI)

Our test results easily meet the IBI requirements and is a testament to the effectiveness of our gasification process that scales across both product platforms. More specifically for carbon removal we are seeing Carbon Content > 94%, H:C Ratio < 0.3 (highly durable, 80% after 100 years), and PAHs < 0.3 mg/kg.

Path to 1 GT Carbon Removal: Sites Needed

Solving the climate crisis will require massive amounts of solutions and projects over the next decade. We are working with financing and project development partners in developing turnkey project offerings that would make it simple for customers to access our solutions. Please fill in this form so we can pre-qualify your site and develop a deployment schedule over the next few years. 

Outreach Events


APL participated in VERGE 2022, a climate tech event held by Green Biz in San Jose. Our team successfully integrated our Power Pallets with other distributed energy resources to connect to the grid and provide a real-time power generation demonstration for enthusiasts, government representatives and investors.

Open House

We recently hosted our first open house since shuttering our doors due to COVID. We were excited to bring back a tradition of public outreach and fellowship at our Berkeley headquarters and will extend the invitation to future events via this mailing list. If you’re in the Bay Area, definitely come check us out and hear talks on our climate focus and upcoming projects.

Community STEM Education

As part of a regional program to get high school students enthusiastic about STEM careers, APL hosted two groups of youth who toured our headquarters and asked questions about how to enter the field of renewable energy and regenerative work.

students doing experiment
Berkeley High School STEM Career visit

Community Garden Support

Our community carbon drawdown initiative–Local Carbon Network–continues to supply our SkyCarbon Biochar along with compost tumblers and training in their use for regenerative agriculture to community gardens around the world.

Yonkers Community Garden

Best Wishes!

From all members of staff we wish each and every one of you a fantastic end of year holiday, please ignore your laptops and enjoy family, fun and festivities until next year!

With love and enthusiasm,

—The APL Team

APL Powers The Verge Microgrid Again

ALL Power Labs will be running our latest model Power Pallet, a PP30 v2.01 at The Verge Climate Tech Event being held at the San Jose Convention Center from October 25th – 27th. We’ll be set up outside at the Innovation Plaza on San Carlos St. and providing the base-load power for the microgrid that provides all the electricity used on the display floor by exhibitors as well as on the main stage.

We make continuous improvements to our technology and this PP30 has numerous innovations adopted in this version 2.01. All PP30’s now include as standard equipment DeepSea DSE8610 MKII grid-tie controllers and two-stage CHP system that can output 50 kW of thermal energy. They now feature improved thermal integration and filtration system using a self-cleaning bag-house filter with an ECU-controlled producer-gas heat exchanger that prevents tar and H2O condensation downstream in the filters and engine. We are also on the verge of a production release of our containerized 130 kW Power Pallet Hybrid Biomass Microgrid and Chartainer whose development have been made possible by generous grants from the California Energy Commission. The CEC has been a particularly active collaborator in the development of our newest products.

The biochar byproduct of the PP30s and the high-volume output of the Chartainer are becoming more and more valuable aspects of our business model. The IPCC has identified biochar as a Negative Emission Technology (NET). The high temperatures (~1000º C) reached within our reactors create particularly high-quality biochar, and we carefully tweak our reactors to assure our biochar has the most beneficial characteristics.. We also reduce our footprint and land-use impacts by only using waste feedstock locally sourced from forestry communities, urban green waste yards, and urban farms. Our LCN project then distributes our biochar to local community gardens, urban farms, and home gardeners, closing a tight, highly efficient, and localized system of carbon drawdown.

Key QualitiesValueResults
High Carbon ContentHigher Carbon Removal85% – 95%
High DurabilityH:C Ratio<0.2
   B100% Carbon 100 years>80%
Low PAHVery lean<30 mg/kg
(Lab Test Results)

The current Verge Microgrid is the world’s largest temporary microgrid and for which we supply the base-load power. For 2022 this latest iteration of microgrid will include Li-ion battery storage, a variety of photovoltaic systems, and the latest microgrid controllers. Verge has assembled the largest temporary microgrid in the world using off-the-shelf products to demonstrate the availability today of efficient, cost-effective distributed-energy solutions, a effort central to the mission and close to the heart of everyone at APL.

We have been part of powering this Verge event for many years. We ran one of our v4 PP20s to power the first microgrid assembled for Verge in San Francisco in 2013.

Microgrids can help resolve some of the difficult issues with grid tying small generators like the Power Pallet by avoiding major utility grid connections all together and thereby avoiding all of their regulatory hurdles, scheduled brown outs, and interdependencies. Microgrids, by virtue of their size and organization, can be much more nimble and localized, immune from the vagaries of large complex utilities, and can easily be composed of all renewable power generation.

There will be tours of the microgrid system and we will have our PP30 running at our booth at the microgrid site staffed with members of our team who would love to answer your questions. Do you know the way to San Jose?

APL Summer Open House- Chartainer & 50 kW CHP Demo, Biochar available

After a long pandemic pause, we’re finally restarting our Open House / Open Shop for all interested to come see the works inside All Power Labs. These are always fun and informative events, with a great gathering of folks, and good food and drink for you too.  So get out of the house and join us at our first open house in two years!  The event is free, but RSVPs are needed.

When: Friday September 30th, 2022, 5-7 PM
Where: APL Headquarters, 1010 Murray St, Berkeley

APL open house

Yes, the pandemic hit APL very hard–with markets stopping all around the world–but we were able to regroup and focus on new product development, along with projects here in California.  We’re now back up to reasonable speed, and would love to show you what we were up to during the quiet time.   So come and see the new chapters in our long narrative of solving biomass thermal conversion for broad public use, and “carbon sequestration with benefits.”

We’ve been at this for 14 years now, and priorities in the market have changed multiple times during the journey.  Today the central driver is clearly the critical need for the carbon management and sequestration, and we finally have financial signals to support this outcome from multiple directions.  While the biochar part of our multi-gen proposition has been present from the beginning, it’s only in the last couple years we’ve seen a real revenue signal for biochar.  And even more recently, carbon credits from directed use of biochar are receiving exceptional rates on the voluntary credit markets.  These carbon credits by themselves can now form the central pillar of a recurring revenue project.

Early APL consciously focussed on the electricity portion of biomass thermal conversion potential–as that’s where the need and financial signal was most clear–but in recent years we’re progressively redirecting to a biochar/carbon focus along with other outputs beyond the electricity.  Yes, many projects are still founded on electricity, but every year the carbon and alt outputs (heat and water most importantly) become more central.  This trend will continue.  And our products will continue to reconfigure and optimize accordingly.

New Products

Affirming these new market drivers, this Open House will introduce two new products for APL. Both of these new products will be on site and operating during the Open House.

1. Chartainer

High-volume, Combined Heat and Biochar (CHAB) pyrolyzer system enclosed within a standard 20-foot shipping container. The Chartainer is currently designed to 250kg/hr biomass input / 50kg/hr biochar output, with expectation to double these rates as the product matures. The demo during Open House will be of the first prototype Charitainer, which not yet fully containerized, with some major components still on open floor.


2. C50kW CHP Hybrid Microgrid

Containerized CHP Power Pallet integration solving typical project balance of system needs, along with battery storage and inverter power delivery flexibility. Design modularity and large switch-gear cabinetry allows for customization to match specific project needs. During the Open house the system will be charging an EV with a level 2 charger.

Click here for more info on each of these new products.

Garden bags and super sack volumes of biochar will be available for purchase during the Open House.  Smaller samples will be given away for free.  In house bochar expert, Austin Liu, will offer a clinic on maximizing the benefits of biochar based on our ongoing research on co-composting with biochar.

Data is accruing from controlled trials in both composting and plant growth through our work both here in California and across the sea with our engineering group in Modena, Italy. Test results on biochar properties from the Chartainer output are also accruing; showing exceptional cleanliness, high C:H ratios, low PAHs, and the quasi-activation and conductivity we would expect from our very high temp, partial reduction, tar cracking making method.

We’re very excited about this growing dataset supporting the unique properties of our biochar, and its performance in practice through co-composting and following soil/plant growth. There’s lots to talk about in person at the event.

In sum, we made it through the pandemic, and lots of good things are happening. We hope to see you next Friday, Sept 30th at APL in Berkeley.

Jim Mason
Founder & CEO

Co-composting Manure with Biochar to Meet Global Methane Goals

This paper in Environmental Science and Technology journal
found that biochar-composting reduces CH4 by 79%, compared to
composting without biochar.


Livestock are the largest source of anthropogenic methane (CH4) emissions, and in intensive dairy systems, manure management can contribute half of livestock CH4. Recent policies such as California’s short-lived climate pollutant reduction law (SB 1383) and the Global Methane Pledge call for cuts to livestock CH4 by 2030. However, investments in CH4 reduction strategies are primarily aimed at liquid dairy manure, whereas stockpiled solids remain a large source of CH4. Here, we measure the CH4 and net greenhouse gas reduction potential of dairy manure biochar-composting, a novel manure management strategy, through a composting experiment and life-cycle analysis. We found that biochar-composting reduces CH4 by 79%, compared to composting without biochar. In addition to reducing CH4 during composting, we show that the added climate benefit from biochar production and application contributes to a substantially reduced life-cycle global warming potential for biochar-composting: −535 kg CO2e Mg−1 manure compared to −194 kg CO2e Mg−1 for composting and 102 kg CO2e Mg−1 for stockpiling. If biochar-composting replaces manure stockpiling and complements anaerobic digestion, California could meet SB 1383 with 132 less digesters. When scaled up globally, biochar-composting could mitigate 1.59 Tg CH4 yr−1 while doubling the climate change mitigation potential from dairy manure management.

Environ. Sci. Technol. 2022, 56, 15, 10987–10996
Publication Date:July 14, 2022

APL Wins Another SBIR Grant

The U.S. Department of Energy has awarded All Power Labs (APL) a Small Business Innovation Research (SBIR) grant for their renewable energy submission in the amount of $200K to develop Distributed Energy Resources (DER).

The SBIR program, also known as “America’s Seed Fund,” grants are distributed annually by the U.S. Department of Energy in various topic areas for small businesses. APL was previously an awardee of a National Science Foundation SBIR grant in 2016, which was used for the development of their Power Pallet systems.

During Phase I of this SBIR grant APL will be developing support infrastructure for the deployment of APL’s DER in the form of it’s 130 kW Power Pallet Hybrid Biomass Microgrid Container.

PP50 Hybrid configuration infographic

Systems for training, finance, biomass management, and biochar distribution along with the related community frameworks are all being developed in this phase using our Local Carbon Network to coordinate the program on the ground. This infrastructure will not only support the deployment of APL DERs, but can also be used to facilitate or enhance various other renewable microgrid projects.

The objective of Phase I funding is to establish the technical merit, feasibility, and commercial potential of the proposed Federal Research/R&D efforts and to determine the quality of performance of the small business awardee organization prior to providing further Federal support. If APL successfully completes Phase I and applies to Phase II, they would be eligible for $1 million to implement the Phase I design.

“We are very excited and proud to be recipients of an SBIR award: the SBIR program is a highly competitive and crucial part of America’s funding for innovation in the small business world,” said APL Grants Manager, Justin Knapp. “This Phase I award is a strong validation that APL technology is meeting real-world needs and has a huge capacity for scaling and commercialization. This Phase I award will increase awareness on how APL’s community-scale bioenergy systems can be integrated with other renewable solutions to improve energy infrastructure, waste management, and climate resiliency.”

This DOE grant followed APL’s recent participation in the Water, Energy and Technology (WET) Center’s Valley Ventures Accelerator program, completing their participation in the fifth cohort which was held virtually due to the COVID-19 pandemic.

The Valley Ventures Accelerator is a program within the Water, Energy and Technology (WET) Center at Fresno State where companies engage closely with industry leaders, investors, and fellow entrepreneurs in the agriculture, water, and energy-technology space. The accelerator aids startups and companies with overall product development, networking, and sales.

Holiday Pyrolysis Party and Open House

All Power LabsLocal Carbon Network

Friday, December 13th, 5-7 pm
FREE!  But please RSVP here.


Chestnuts will likely roast, and walnut shells will certainly thermally convert into Electricity, Heat and Biochar, at this year’s All Power Labs and Local Carbon Network holiday party. 

In year’s past, we’ve celebrated the end of another year deconstructing fire into its constituent components with CHP hot tubs, GEK kit welding marathons, and gasifier powered pyrotechnics.  This year we’re “simply” demoing our master synthesis between a multi-gen biochar making machine and the entry of its biochar into a climate optimized co-composting solution.  Thermodynamics and Biology- together at last!  

Attendees at this FREE event will get to meet the APL and LCN teams, see both the PP30 and our new prototype CHARtainer in operation.  Yes, we are finally developing a large shipping container-based Biochar optimized system, and have the prototype currently operating on site.  

The new CHARtainer is built for 10x the biomass throughput capacity of the Power Pallet, and 30x the Biochar output.  It is a multi-stage pyrolyzer that is focussed on making the fancy high temp, Tar-Free, Geo-Conductor char which we have found so powerful for co-composting purposes.  And it comes with a clean-burning, regulatory emissions meeting flare with native heat exchanger integration, for Combined Biochar and Heat applications.

We plan to deploy a couple of pilot projects with this machine in California during 2020.  We invite others interested in early testing/proving projects to write for more info on what we’re up to.  

The Open House also marks the last day of our 40-30-20 $15,000 discount promotion for 2020 Power Pallet sales.  We’ve made machine reservations very easy with the highly reduced deposit requirement of $5,500.  We’re trying to make it attractive for you to book reservations, so we can present a full queue to our supply chain vendors.  And thus get the volume cost and price of this product headed back in the downward direction. 

For more information on this sale, and/or to reserve a machine for the coming year, see the promotional announcement here, or write us at

Co-composting with Biochar for Agronomic & Climate Benefit
The highlight of these Open House events is Austin’s talk on deep Biochar esoterica and its interactions with composting systems.  Austin has developed the most broad and powerful synthesis of Biochar parameters and optimizations that I have seen to date.  Many others in the field have been similarly impressed.  So come see the curtains pulled back, and the Grail shine forth in blinding clarity! 

More practically, if you’ve had unpleasant experiences with composting (foul odors, slow decomposition, vermin, flies, angry neighbors, etc.) come see how that can be fixed.  We’ll be showing off our new in-house composting experiment, where you can see the effects of co-composting biochar vs composting without biochar in a side-by-side comparison.


Some links for those who can’t make it, or want to do their homework beforehand:
 1.  “All Biochars are not Created Equal” Intro to the APL biochar scenario.

2.  Open House Biochar Presentation Austin’s deck from the last round of this talk.  Updates for this Friday still in process.

3. “A Perspective on Terra Preta and Biochar”  Austin’s longer synthesis and deep dive into both historic Terra Preta and our contemporary options.

   The “master integration” combines this co-composting process with APL CHP machinery to transform biomass residues into multiple types of value and climate impact.  Adding the co-composting scenario out the end significantly multiplies the carbon drawdown impact of the biochar generated.  By optimizing for “active biological sequestration of carbon”, each unit of carbon put into the system can multiply to many units of CO2e impact.  And as it is a living solution both above and below ground, the benefits grow and compound over time.  

“Carbon Sequestration with Benefits” is a very different scenario than the various inert CO2 storage scenarios or simple reuse of CO2 post-capture.  The revelation is we can “seed” carbon systems to do the drawdown work for us, at 10s of X of multiples beyond our original action.  And we can identify the pathways and scenarios which will have the greatest multiplier effects.

These carbon multiplier pathways are summarized in the flow chart below.   The chart assumes the current 5% biochar yield rate of the APL electricity and heat focused equipment.  Higher yield rates are of course possible with other types of biochar focused equipment, like the prototype CHARtainer onsite.

Biomass to Biochar to Cocomposting Flow Rev 01

So come join us Friday while we explore the odd path of Burning things to save the world, in close collaboration with soil microbes and their symbiotic plant friends.

Facility tours start at 5pm.  Talk starts at 6pm.  Event goes to at least 7pm, and usually later.  We’re at 1010 Murray Street, Berkeley, CA
Please RSVP here so we know who is coming.

Jim Mason
All Power Labs
Founder, CEO

All Power Labs and Local Carbon Network

The 40-30-20 sales event


40 pre-orders available for the Power Pallet PP30, to enable lower-cost supply chain in 2020.

A year ago, All Power Labs released the Power Pallet PP30 Cogen as our completely new generation of the Power Pallet.  This successor to the PP20 incorporates all we’ve learned in the last decade to make biomass gasifiers ready for daily use in the world, and carbon-negative power and products ready to scale for our climate management needs.  Critical design changes focused on increasing power-generation capacity (both electricity and heat), reducing O&M costs across the board, and generally increasing reliability for high uptime use cases. Units are now being shipped regularly, with new machines recently installed in:

We’re now ramping our production capacity in 2020 to fulfill customer orders and planned multi-unit project deployments.  Our supply chain to make the Power Pallet now spans India, Philippines, China, and US suppliers, with final assembly in Berkeley, CA.  To improve the cost, quality and regularity of delivery through this supply chain, we need to increase our order quantities. The route to scale for requires an ever-lowering price and ever-increasing value–and getting there requires increased throughput of a standard manufactured solution. We have come up with a campaign to book the majority of our 2020 production over the last month of 2019. The campaign provides a compelling package for our customers, and will equally enable us to close larger supply agreements with our supply partners.  Booking a year of orders ahead will also strengthen the Series A fundraising effort currently in progress. Yes, we’re finally raising outside capital to grow the internal capacity of APL beyond its current limits of self-funding. Here’s the deal. Between now and December 15th only, we’re offering special pricing and low deposit payment terms for 40 units of PP30 Cogen units.  The detail terms are as follows:

  • Price – $66,550 MSRP – $15,000 discount = $51,550
  • Deposit Payment – $5,500
  • Balance payments –  40% at 8 weeks prior to shipment, remainder before shipment
  • Cancellation and Refund: 100% refund with 30-day notice.
  • Total Quantity Available – 40 units
  • Reservations are given on a first-come-first-serve basis.  You schedule the delivery time in 2020 that works for you.
  • Add-ons beyond the standard full-featured machine (i.e. adding continuous feed and catalytic emission system) are extra

 The motivation here is to encourage those with plans for multi-unit projects to start the deposits for the related machines.  A deposit of $5,500 vs the usual 60% of invoice makes the deposit for a multi-machine purchase, multiples less than a typical single machine deposit.  And with a mostly filled queue for 2020, we can start the larger purchase orders that reduce costs and justify this price reduction. This discount price and deposit terms are only available until December 15, 2019.  Please be serious on your intent to complete the purchase if you start it. However, there is a 100% refund of deposit with 30-day notice if your plans change.  We are trying to make this helpful and risk reduced for both you and us.

To place your reservation, or to ask questions about the sale or PP30 machine, please contact sales@allpowerlabs. Please include 40-30-20 in the subject line so we can keep track of the sale-related actions.

What’s new in the Power Pallet

For those new to APL and the Power Pallet, here are the details for the generation change between the PP20 and PP30.  At the launch last year we posted a full inventory of PP30 changes by subsystem, explaining motivations for each development, and what users should now expect in operation. The quantitative rendering of these changes are performance outcomes are in the Comparative PP20 vs PP30 Spec Sheet.  A short summary is below

  • A totally re-designed filtration system that eliminates charcoal gas filter media and production of condensate. This redesign eliminates the most labor-intensive and frequent maintenance operation.
  • A larger engine and more efficient generator. Our new, high compression ratio and longer format generator results in higher power output and greater efficiency.
  • Standard enclosed genset for quiet operation and weather protection. 
  • Standard grid-tie / paralleling hardware.  Most everyone asks whether the Power Pallet can push electricity directly into the grid, or whether it can integrate with their existing solar / micro-hydro / small wind turbine microgrid. Grid-tie and paralleling hardware used to be an expensive option, but now all Power Pallets have this as a standard feature.
  • Standard CHP water heating, with higher efficiency. The new CHP system uses multiple stages of waste heat recovery to double the available heat compared to the PP20 with the CHP option. The PP30 makes available up to 2kW of thermal output per 1kW of electrical load.
  • Indirect heating of the drying stage. By indirectly heating the drying stage of the gasifier using recovered waste heat, we maintained the efficiency afforded by recovering waste heat while eliminating another labor-intensive maintenance operation—cleaning soot out of the drying vessel.
  • Larger char-ash vessel, and larger cyclone dust can. This allows the PP30 to run longer sessions at the same loads as the PP20. 

 In the year since launch, we’ve refined many details of the productization and manufacturability.  The core functional changes remain the same, but system polish and ability to manufacture on schedule, with controlled costs and quality control, have greatly improved.  We now have a frozen design that is in regular manufacture, and progressively in larger supply chain, to enable the scaled deployments we know many of you are planning for the coming year(s).

 We hope this 40-30-20 sale will help both you and APL get to the scaling we’ve all worked so hard to prepare for over the last decade.  We’ve all learned that solving gasification is hard. Many people and companies have come and gone over the challenge. It’s a blessing that we’ve been able to work with continuity on the problem for over a decade, and can keep rolling in new learning.  More improvements are on the way, now enabled by the new foundation of the Gen 2 machine.  But as for today, we are very satisfied where the machine is, and are signing off on its fundamental components for growth production. We hope you can help us make this step change in our supply chain happen. 

Thank you for your continued interest in APL and for following the long arc of our story.  I continued to be amazed how many people surface today, and start by saying, “you know, I was watching you years ago with the GEK kits, back in  . . .”.

 Jim Mason
All Power Labs

A Perspective on Terra Preta and Biochar

The Modern Discovery of Terra Preta, and a Brief Modern History of Biochar

In the Amazon Basin, there exists thousands of hectares of cultivated plots consisting of unusually fertile black soil, termed Terra Preta de Indio — “dark earth of the Indians” — called Terra Preta for short. These soils are many hundreds if not thousands of years old, and have remained remarkably fertile in spite of the tropical rainfall, which accelerates the weathering of soil and the leaching of water soluble nutrients. Modern scientific interest in this material began with a Dutch scientist named Wim Sombroek, whose book Amazon Soils, published in 1966, began the modern investigation into the nature of these soils and attempts to discern their secret. It was established that these soils were artificially cultivated by an established civilization that practiced agriculture, since the soils were always found with human artifacts and near the ruins of human settlements, and often had fired-pottery fragments buried in it. It was also established through analytical examinations of the soil that these soils contained pyrogenic carbon (carbon from charred materials). These soils were seemingly permanently fertile, with double the crop yields compared to surrounding soils and holding about three times as much phosphorus and nitrogen, while consisting of about 9% carbon, whereas surrounding soils contain around 1%.

Interest in the use of charcoal as a soil amendment began to grow dramatically in the 2000s, which can be credited to various publications by Prof. Johannes Lehmann, which popularized to the scientific community the concept that the production and use of charcoal could not only supply energy, but that the charcoal could improve soil fertility while sequestering carbon to fight climate change, first proposed by Sombroek. At that time, the term agrichar was variously used to specify that the application of interest was the agricultural application of charcoal, but since the term “agrichar” was the trademark of Pacific Pyrolysis company, the term biochar was coined, and the term was officially adopted at an international scientific conference in Birmingham, England, in 2009. This is not to say that charcoal had not been studied for its agricultural applications; examples of scientific study of the use of charcoal as a soil amendment go all the way back to the 1700s [See the book Geotherapy by CRC Press, Chapter 11 — “Biochar: the Field Experience”, for an account of the study of agricultural uses of charcoal in the 1700s, 1800s, 1900s, and 2000’s], but the mixed results, the lack of mature analytical techniques for the biochemistry of soil, and the lack of a distinguishing term and concept to keep agricultural charcoal research from being lost among all the other research done on charcoal conspired to keep biochar research from getting the attention and funding it deserved.

Those of you who are new to biochar may wonder why so much research was needed. Very early on, it became clear that simply adding charcoal to the soil was not all there was to it. Just as studies on the use of charcoal as a soil amendment in the 1700s and 1800s had mixed results, early attempts to simply add charcoal to soil found that in many instances of direct application, charcoal seemed to have an initially counterproductive impact on the soil, robbing the plants of nutrients as the charcoal adsorbed nutrients out of the soil too aggressively and bound these nutrients too tightly. Scientific research focused on what the difference was between modern biochar-amended soil and terra preta, and how to reproduce the amazing fertility observed in terra preta.

Since that time, academic research on biochar has exploded, in what could appropriately be called a biochar renaissance. In 2017, the number of scientific papers published on studies of biochar exceeded the papers on compost, and the pace of research has only accelerated internationally.

A shift in thinking: Should the objective of biochar research be to reproduce terra preta?

An unspoken meta-narrative that emerges from among much of the study of biochar early on in the biochar renaissance implied that the objective of this study was to reproduce terra preta. Wim Sombroek’s own challenge to soil scientists prior to his death in 2003 was to develop terra preta nova, “new terra preta”, to address the problems of soil fertility and climate change. Even if he meant it figuratively, and did not imply this as a charge to faithfully reproduce the original terra preta, the way this challenge was framed seems to me to have colored the discussions around the topic of biochar.

Although various hypotheses abound, nobody is exactly sure of how terra preta was produced. Bold claims by various proponents of cultured “effective microbes” and enthusiasts of specific preparations of biochar to have reproduced terra preta are unwarranted and baseless. There simply is not enough evidence for us to deduce how terra preta was made, and claims by anyone who is not an anthropologist with field experience in the Amazon ought to be received with skepticism. Even knowing that terra preta contained charcoal does not give us much to infer; knowing that charcoal was involved still does not tell us what feedstocks and charring processes were used, what additional processes were involved, how it was incorporated into the soil, how long it resided in the soil until it started to show benefits, and what proportions and schedule of incorporation were used. Each of these variables has an influence on the agronomic qualities of the resulting char. There are even some who dispute that terra preta is biochar amended soil, due to the observation that terra preta seems to reproduce itself.

The objective of reproducing terra preta may be partially motivated by notions of solving a mystery and recovering lost ancient knowledge, but ultimately, in light of the body of knowledge and the practical applications and benefits of biochar that have been discovered, terra preta is irrelevant, having served its role as an inspiration. The true objective is to improve long term soil fertility and resilience, especially in the face of intensified climate change. A parallel objective is to draw down and store carbon. In as much as we achieve those ends through biochar research and policy implementation, it does not matter whether or not our efforts reproduce terra preta. The original terra preta was produced in an oxisol (a soil order of highly weathered tropical soil with oxide-rich subsoil), contains charcoal made of tropical woods, and was shaped by the soil microbiome of the Amazon. In each agricultural region, differing soil parent material, differing climate, differing crops, differing soil fauna, and differing microbiome make the goal of faithfully reproducing terra preta inappropriately narrow. Exporting terra preta in order to propagate its microbiome would not be appropriate either; besides the microbiome not necessarily being well suited to other climates, soils, and crops, transporting soil brings with it the risk of introducing invasive species.

If a particular method of application of biochar yields good results, whether or not it faithfully reproduces terra preta is irrelevant; it is not possible to ever verify that any method successfully replicated terra preta nor its production method since there are no written records documenting its production. It is enough that terra preta inspired the investigations into biochar that resulted in the discovery of the known benefits and effective agronomic applications of biochar.

Is Terra Preta Charcoal Amended Soil?

The idea that terra preta is anthropogenic charcoal amended soil is not without controversy. Proponents of the hypothesis that terra preta is anthropogenic charcoal amended soil support this hypothesis on account of several findings: analytical methods examining the microstructure of the carbon in terra preta confirm that it is pyrogenic, and terra preta was often found to have pottery shards incorporated into it (whether incidentally or by design). Inferring from the thousands of hectares of land mass cultivated as terra preta, along with the depth of the terra preta and how thoroughly the charcoal is incorporated into the soil, the idea that terra preta formed by gradual incorporation of char from repeated massive forest fires seems implausible, especially given that it is found in the Amazon rainforest.

The strongest argument against terra preta being anthropogenic comes from the observation that terra preta regenerates. The late William Woods, one of the pioneering biochar researchers who contributed to the biochar renaissance, observed that in Brazil, terra preta has been mined and sold as fertile topsoil and potting mix for decades. The miners dig away the top 20cm of terra preta off the top of the mining area, and move on to another area, leaving the mined area to recover for 20 years. Over the course of time, the terra preta thickens as it regenerates itself from the forest litter that falls on it. By this account, it would appear that terra preta is merely a special form of forest litter compost. This also suggests that much of the observed depth of terra preta may not be originally cultivated material, but later growth due to the conversion of forest litter.

3 men mining Terra preta
Terra preta being mined. From the 2011 BBC Documentary on terra preta titled “The Secret Of Eldorado”.

The regeneration of terra preta from forest litter suggests that the microbiome of terra preta may have as much of an influence as added charcoal, imparting the character of the underlying material on organic material that decays upon it, analogous to the propagation of a sourdough starter “mother dough” into freshly added flour. However, it is important to point out that the charcoal content of terra preta cannot regenerate and cannot simply reproduce; pyrogenic carbon requires high temperatures to form its associated microstructures, and does not form in the decaying organic matter that builds up on terra preta. Furthermore, from the few videos and photos where terra preta mining can be observed, it appears that the material is not black like known examples of charcoal amended terra preta, but rather brown, suggesting that though this material is identified with terra preta, it probably does not contain charcoal, unless soil fauna have mixed deeper layers of soil with the new material (a process known as bioturbation), introducing charcoal into it from the underlying terra preta.

If this is so, what is going on? What is the relationship and relative contribution of charcoal and the microbiome of terra preta? And what does this mean for our theories of the origins of terra preta and our attempts to optimally use charcoal as a soil amendment?

It turns out that terra preta is not the only soil that regenerates. The regeneration of terra preta appears to be an example of negative priming.

Negative Priming

Priming describes the phenomenon of the reduction of humus from soil and a multiplication of microbial biomass upon the decay of organic residues added to the soil, such as forest litter falling upon the ground in the autumn. As the microbial decomposers begin to consume the organic residue and multiply, there is a loss of humus and an increase in microbial biomass (called the priming effect), suggesting that the decomposition of fresh residues results in further decomposition of existing humus. As the decomposition finishes, the microbial biomass gradually reduces as the level of soil humus increases, resulting in a net increase in the amount of humus. This effect is observed in forest soils, and is termed negative priming.

schematic illustration of the changes in soil carbon fractions
A schematic illustration of the changes in soil carbon fractions when new forest residues are added, taken from Figure 12.5 from the Soil Organic Matter chapter of “The Nature and Properties of Soils”, 15th ed. The priming effect is called out in this figure, but negative priming is not labeled. Negative priming is the subsequent increase in soil humus levels following the reduction in microbial biomass.

The regeneration of terra preta appears to be negative priming at work. The microbiome and charcoal are both involved, because the addition of charcoal appears to modify the microbiome of compost and soil. For example, the addition of biochar to compost (not the mixing of biochar with finished compost, but the addition of biochar at the beginning of the composting process) has been found to significantly abate the methane emissions of compost by favoring methanotrophs (methane eating bacteria) over methanogens (methane producing bacteria). Terra preta has even been found to foster mycorrhiza and host higher populations of free-living diazotrophs (nitrogen-fixing bacteria which are not bound to the root nodules of legumes). [See Geotherapy: Innovative methods of soil fertility restoration, carbon sequestration, and reversing CO2 increase, ch. 10, Geology into Biology, by David Yarrow. p. 208 and p. 219.] These are merely a couple of examples; compost and soil are home to tens of thousands of species of microbes, and biochar likely also exerts selection pressures on these microbes that result in significantly different proportions of various species, resulting in a significantly different microbiome from the surrounding soil. It would be this altered microbiome that colonizes and decomposes the new forest residue landing upon it, transforming it into regenerated terra preta populated with the same microbiome, exhibiting all of the characteristics to the parent material due to the microbiome, while lacking charcoal.

In our own field work with biochar at Gill Tract Community Farm in Albany, California, we have observed that biochar significantly alters the behavior of compost piles, resulting in compost with noticeably different characteristics. In 2018, Gill Tract Community Farm partnered with the Local Carbon Network as an early adopter of our biochar. Wary of the break-in period of suppressed plant growth incurred by adding biochar directly to soil, we decided to send the biochar through their compost piles as an exploratory application. Prior to adding biochar to their compost piles, the piles would heat up to about 130˚F, but the heat would dissipate when the piles were turned, and would not recover. After adding biochar to the compost pile, the compost would heat up to 155˚F, and would remain that hot for nearly a month. By the end of six weeks of composting, the piles would often be at temperatures over 130˚F.

Furthermore, the raised beds built using biochar compost had some notably different behavior. The raised beds at Gill Tract Community Farm at the time these photos were taken were made using an extremely compost-rich blend; each bed consisted of a blend of 20% compost made on-site, 40% purchased compost, and 40% soil. (Since then the composting program has significantly expanded, and now, hardly any purchased compost is used in the raised beds.) This mixture is packed into a frame while damp, and the frame is removed, leaving the bed unsupported, for better drainage and aeration. The raised beds made with biochar compost remained intact throughout the season, and maintained excellent aggregate stability, which appeared to be due to increased fungal activity, whereas the raised beds made with conventional compost collapsed and shrank away over the course of the season. We suspect that some of the shrinkage and collapse is due to incomplete decomposition in the compost piles without biochar.

Electron Transfer Hypothesis

Why would biochar modify the behavior or even the composition of the microbiome of the compost and the soil? In recent years, emerging research suggests that biochar’s facilitation of electron transfers among various soil microbes may play a role. For example, it was found that biochar helps abate N2O emissions from soil because of its role in transferring electrons. In 2017, it was published that biochars prepared at different temperatures were found to exhibit different mechanisms of electron transfer. In order to understand why this would have an influence on the behavior and composition of the microbiome, a bit of background explanation is needed.

The microbes in soil often carry out biochemical processes which leave them with an imbalance of electrons — in some cases, a surplus that they need to discharge, and in other cases, a deficit of electrons which they need to neutralize. These charge imbalances can build up to the point where they become bottlenecks on microbial activity. To overcome these imbalances, bacteria naturally grow microbial wires, called pili, to reach out and touch microbes carrying out electrically complementary activity in order to transfer electrons. The electrons obtained by these transfers are utilized in converting certain mineral nutrients into usable form. (For example, see this article on pili electron transfer in geobacter species.) Unfortunately, these microbial wires are materially expensive to grow, since they are made of protein. The number of complementary microbes that can be reached is limited by the length and the number of pili that can be grown, and the pili have fairly limited conductivity.

This electron transfer soil service is where biochar appears to make a difference. Biochar affords bacteria two mechanisms by which they can transfer electrons more efficiently than direct electron transfer between microbes touching each other using pili:

  • the geobattery mechanism, dominant in biochar produced at temperatures under 600˚C, which charges and discharges electron exchange chemical groups on its surface to exchange electrons with microbes that come in contact with these groups, and
  • the geoconductor mechanism, a much faster and much more prolific electron transfer mechanism, found in biochar produced at temperatures over 700˚C, which directly conducts electrons between microbes in contact with the char. A macroscopic piece of biochar visible to the naked eye can host millions of bacteria and archaea on its surface, along with contact to fungal hyphae. By directly conducting electrons among them, it serves as a microbial marketplace where electrons are the currency of exchange, removing the electron transfer bottleneck for all of their relevant biochemistry.

As charcoal is heated past 600˚C, the amorphous carbon structure begins to self-organize into more stable structures. The carbon rings form small graphene-like sheets, which are electrically conductive. As the processing temperature increases, these flecks grow and dramatically increase in conductivity as the temperature exceeds 700˚C. The following illustration (used with permission) from Biochar for Environmental Management shows the relationship between the char processing temperature and the resulting microstructure:

At the highest temperatures and longest time exposures, the microstructure of the carbon matrix of the char converts to that of graphite.

It appears that soil microbes thrive in the presence of biochar because they exploit the electron transfer services of the biochar. A quote from the news report on this discovery:

[Prof. Johannes] Lehmann and the members of his laboratory had struggled to understand why microorganisms thrived in the presence of biochar. The group removed soil phosphorus, making the environment inhospitable. They ruled out water and nutrients. They discarded the use of biochar as a food source because microorganisms cannot consume much of it. Through [Dr. Tianran] Sun’s background in environmental chemistry, the scientists found that microorganisms may be drawn to electrons that the biochar can transport.

Biochar and the Natural Selection of the Terra Preta Microbiome

In light of the electron-transfer soil service provided by biochar, I propose the following theory of terra preta’s origin and apparent self-propagation from forest litter:

The original terra preta was charcoal amended soil, and was cultivated systematically because of the observed benefits. (It seems unlikely that resources and labor would have been set aside for widespread systematic production of charcoal amended soil if the charcoal required long periods of aging to offer any agronomic benefit.) The presence of charcoal modified the soil environment, favoring microbes that best exploit the soil services offered by the charcoal (such as electron transfer), resulting in a modified soil microbiome. This modified microbiome then self-propagated up into the decaying forest litter materials that accumulated on top of it, resulting in an increase in topsoil that exhibits the characteristics of the decomposed soil organic matter in underlying charcoal-amended soil.

Co-composted Biochar

One additional confounder must be accounted for in informed speculation about the origins of terra preta: biochar is not necessarily immediately beneficial to the soil if it is directly mixed into soil as a soil amendment. In many of the early studies examining the agronomic applications of biochar, it was found that adding biochar directly to the soil was not immediately beneficial. There would be a break-in period during which biochar was found to suppress plant growth, or even repel roots and soft-bodied soil creatures like worms. This break-in period has variously been found to take as long as a couple of years in the worst instances. It is speculated that a couple mechanisms may be at work:

  • Biochars that were produced at lower temperatures, which are sometimes not fully devolatilized, start out hydrophobic, due to the presence of tar — condensed from the smoke released by pyrolysis. Until the tar is broken down (primarily by fungi that can digest tar) and the char is colonized by beneficial microbes, the tars have a preservative-like biocidal effect.
  • Biochars that are fully devolatilized, and especially biochars that have been exposed to reduction reactions (which we will look at in detail in later installments) have significantly higher adsorptivity, and behave like carbon filters in the soil, aggressively adsorbing and binding to nutrients, rather than loosely binding the nutrients like nutrient exchange sites in mature soil organic matter.

If this is the case, how might the indigenous Amazonians have prepared their charcoal for use in soil in the preparation of terra preta? Although we cannot know with certainty, we can speculate on what methods would have been accessible to them while yielding compelling benefits.

In the wake of various experiments and studies that reported that direct application of biochar to soil did not result in compelling benefits, various methods have been proposed to “charge” the biochar, “break it in”, and populate it with beneficial microbes for use in soil. Such methods include mixing char with fertilizer, manure, or compost, all of which have been more effective than direct application of biochar to soil. In the course of examining the scientific literature, and in our own experimentation, we have settled on co-composting biochar as the best practice for preparing biochar for use in the soil. Co-composting refers to the practice of mixing biochar with compostable materials, and letting the mixture go through the composting process. It is not to be confused with the practice of mixing biochar with finished compost The “co” in “co-composting” refers to the fact that the biochar is with the compost through the composting process, but does not decompose even though it influences and contributes to the process. When biochar is co-composted, the resulting biochar compost is immediately beneficial to soil. Furthermore, the addition of biochar to a compost pile reduces odor, particularly ammonia. [recently published paper by Lehmann’s soil science group at Cornell University found that charcoal has an incredible capacity to take up ammonia, both through adsorption and chemically binding to ammonia, thereby reducing ammonia odors and emissions.]

At Gill Tract Community Farm, the pilot biochar deployment site for the Local Carbon Network, co-composted biochar was tested in raised beds and compared against raised beds prepared with regular compost. The results were rather unexpectedly dramatic. Every plant that received co-composted biochar exhibited incredible fertility, though no additional fertilizer was used in any of these comparisons:

Collard seedlings

What seems to happen when biochar is co-composted is that the char adsorbs a hydrophilic porous coating of decomposition products, rich in nutrient exchange chemical sites and electron exchange sites. This coating seems to confer upon the char most of the observed benefits of char which has “aged” in the soil. Since this benefit is obtained so rapidly with co-composting, especially compared to surface oxidation by aging, it seems more plausible that this was discovered by the indigenous peoples of the Amazon. Furthermore, during the composting process, large quantities of nitrates which would otherwise be lost to off-gassing or lost through the leachate (the liquid that sweats out of compost) have been found to be captured on the biochar. These captured nitrates then serve as an abundant source of fixed nitrogen for the plants that receive the biochar, resulting in broad, deep green leaves and vigorous growth. This is the sort of compelling observed benefit that may have motivated the Amazonians to practice widespread systematic use of charcoal and compost to prepare newly cultivated land for agriculture.

Speculations on the Origins of Terra Preta

With such dramatic benefits immediately available to the crops that received co-composted biochar, here is what I suspect led to the discovery of terra preta by the ancient indigenous Amazonians.

Charcoal waste from household cooking fires were likely thrown out with household food waste and human waste. Charcoal may have even been deliberately used to control odors from manure and fecal waste. Since all of their waste consisted of biodegradable materials (with the exception of broken pottery), the mixture of char and waste essentially composted whether they intended it to or not. The observation that plants growing in and around their decomposing waste piles exhibited unusual vigor may have led to experimentation with deliberately amending agricultural soils with this composted mixture and systematically preparing compost with specially prepared charcoal for amending agricultural soils. The subsequent abandonment of farmland due to the collapse of the population resulted in the Amazon forest growing back in over the terra preta, and the accumulation of leaf litter over the terra preta then continued to increase the soil organic matter via negative priming, as the microbiome of the charcoal-amended soil propagated upwards into the forest litter, which we observe as terra preta reproducing itself.

Concluding Thoughts

Even though it is not possible to conclusively determine the method by which terra preta was produced because we have no surviving record of the process used by the ancient indigenous civilizations of the Amazon, at this point in our history, it suffices that the mystery of terra preta has inspired the scientific study of biochar, along with widespread experimentation, which has yielded so many useful applications of charcoal. With insights from soil science, we understand that terra preta is not the only soil that increases its topsoil humus/soil organic matter from plant residues (such forest litter) that accumulate upon it; this is the expected behavior of healthy soils that receive regular accumulations of plant residues. We also now understand how biochar can significantly modify the soil environment, and therefore, the conditions that favor and select for a different soil microbiome, which then propagates into organic residues that decompose upon it. With even just the agronomic benefits of co-composted biochar, produced by methods informed by these findings, we can significantly improve the fertility and resilience of our agricultural soils, and it would not matter whether or not our methods faithfully reproduced the original terra preta. What is needed now is deployment and widespread application of what we know. Whereas the ancient indigenous people of the Amazon cultivated many thousands of hectares of poor tropical oxide soils into some of the most fertile agricultural soils in the world, we in the modern developed world are destroying ours with chemical fertilizers and conventional farming practices, and those who know about biochar, though having access to mechanized farm equipment have barely matched the acreage cultivated by the ancient Amazonians. The benefit of all of our scientific insights only come from putting them to practice.

Coming up next: The right way and the wrong way to do biomass energy

Biochar and Biomass energy are intimately related through their use of combustible biomass feedstocks. In the next article, we’ll take a look at how biomass energy can be practiced in a manner that benefits the climate.

Biochar and Bioenergy 2019, Fort Collins CO

APL team member at the booth
APL team member Austin Liu at our Biochar & Bioenergy 2019 booth

All Power Labs recently attended the Biochar & Bioenergy 2019 conference held in Fort Collins, Colorado from July 1–3. Our CEO, Jim Mason, as well as biochar experts Austin Liu and Aidin Massoumi were on hand, to promote our distributed-scale biomass gasifiers, share our work with SkyCarbon Biochar and the Local Carbon Network waste-to-climate products initiative, and soak up the latest knowledge from academics, producers and practitioners in the global biochar community.

The event was hosted by the US Biochar Initiative (USBI) and featured presentations, panel discussions and poster exhibitions from more than 80 experts on major themes in the biochar space, including production and commercial application, environmental remediations, soils and agriculture, and the bioeconomy and climate change.

Our resident biochar expert, Austin Liu, gave two presentations at the conference, sharing his research on gasification’s effects on biochar properties, as well as our work with biochar co-composting and the observed benefits to plants and soils.

We also staffed a booth with videos and literature on our latest biomass-to-power/heat/biochar gasifier, the Power Pallet 30, as well as on the science behind our SkyCarbon Biochar and evidence of its impacts with our farming partners.

Biochar & Bioenergy 2019 was a very exciting opportunity for All Power Labs and the Local Carbon Network project, and we received considerable interest from attendees on our product line, on our equipment at-work in forests and on farms, and on the SkyCarbon Biochar produced through our patented gasification process. Most importantly, we met many new friends and partners to support our goal of scaling community-based carbon sequestration!

If you’d like to learn more about All Power Labs and the Local Carbon Network project, reach out!

Biochar Usage in Dairy Manure Composting

Co-composting dairy manure with SkyCarbon biochar

In the Local Carbon Network, we convert available green waste into value-added ‘climate products’ such as electricity, heat, water and biochar through a carbon negative process that combats climate change on multiple fronts.

The Local Carbon Network uses biomass gasifiers from All Power Labs in Berkeley, California, to produce SkyCarbon Biochar, a clean, porous, high-temperature char certified by the International Biochar Institute and officially listed by the Organic Materials Review Institute (OMRI). When used as a soil amendment, SkyCarbon Biochar can offer a range of powerful agronomic benefits to plant productivity, soil biological activity, water retention, pest management and mineral uptake.

We have found that these results are best achieved through combining or ‘co-composting’ SkyCarbon Biochar with nutrient-rich organic matter at the beginning of the composting process. Through co-composting, the char is biologically ‘charged’ or ‘activated’ with microbes and nutrients that enhance its benefits. In addition, compost piles containing SkyCarbon Biochar tend to reach higher temperatures and stay hotter longer, significantly reducing the processing time and allowing compost to be harvested earlier.

Ontario Agricultural Commodities

In April of this year, the LCN began working with Ontario Agricultural Commodities (OAC), a commercial-scale composting operation in Ontario, California, to implement A/B trials with SkyCarbon Biochar in dairy manure composting. Before partnering with OAC, our experience with co-composting SkyCarbon Biochar had primarily been with green waste composting, and so we were excited to see what would happen when our char was mixed with a dairy-manure composting process.

Experimental design:

Treatment and control test with two dairy-manure compost piles, approximately 200 gallons each, started at the same time. The treatment pile was composed of 10% biochar, 90% manure, the control pile of 100% manure. Total biochar added to the treatment pile was 20 gallons of biochar at start, and 15 gallons later. Moisture was added to piles every three days. Pile temperatures were measured three times a week.

The compost pile with SkyCarbon Biochar achieved and sustained higher temperatures throughout the compost process, and was ready to be harvested eight days before the control pile (indicated by black dot).

As you can see, the compost pile with biochar started hotter and stayed hotter longer than the pile without. Achieving and sustaining higher compost temperatures is particularly important for manure composting as hotter piles eliminate the threat posed by pathogens originating from animals. OAC harvests its piles 15 days after they have reached 131F, and as a result of the elevated temperatures, the SkyCarbon biochar pile was ready eight days earlier than the control pile, a 30% decrease in processing time! OAC staff also observed increased moisture content in the biochar pile, which would improve the overall effectiveness of the compost.

These are exciting results for our first foray into commercial-scale manure composting, and as we continue to combine SkyCarbon Biochar with different types of compost we look forward to testing for the additional known benefits of biochar to composting processing such as reduced GHG emissions, higher pH, enhanced organic matter, and increased nitrogen and other plant nutrients.

The LCN is actively seeking partners to demonstrate the many benefits of SkyCarbon Biochar, so if you are interested in collaborating on a solution that addresses climate change, soil degradation and world hunger, reach out!