21 January 2022 |

Keep Cool Report #0002: Biochar


1,979 words, ~ 6.5 min read

Report North Star

Scale carbon sequestration, promote clean energy production and illuminate the soil enrichment benefits of biochar. 

What is Biochar? 

Biochar is a biocarbon made by pyrolysis, i.e.: the heating of biomass in the absence of oxygen. During the slow baking of biomass, gas and oil separate from carbon-rich solids. The output is twofold: 

  • Biochar, which stores carbon and can enrich soil. 
  • Syn-gas and bio-oils which can be used in renewable energy production and to replace carbon-intensive fuels in other applications. 
Flow chart of how biochar works

Source: Puro.earth

Terra Preta → Biochar → Biocarbon   

Terra Preta: In ancient Amazonia the waste disposal method of choice was to bury and burn. This process, coupled with a favorable set of environmental conditions produced a charcoal soil amendment rich in carbon called terra preta, or “black earth” in Portuguese. While exactly how terra preta came to be remains somewhat mysterious (🤯), its properties and potential uses sparked significant research on carbon dense charcoals.

Biochar: This research led to biochar, described above. 

Biocarbon: Many in the space believe that the word “biochar” should evolve and opt instead for the broader term “biocarbon”. We understand this argument; for the sake of continuity, we will use “biochar” throughout this report.

Why it Matters 

Normally, when biomass decomposes on the earth’s surface (or when it is burned), carbon and methane escape into the atmosphere, contributing to the greenhouse gas (“GHG”) effect. In contrast, when biomass is broken down by pyrolysis, the resulting biochar sequesters most of its carbon, offering a stable way to store it for centuries. 

Additionally, using biochar in applications like water filtration can reduce the need for new material extraction and land use. For example, many competitive water filtration products are coal-based, whereas biochar is made from existing waste.

Every challenge, an opportunity

Here are the climate challenge areas in which biochar can have outsized impact. (to go deeper on these climate tech challenge areas, checkout our content overview

1. GHG Capture and Storage 

The Opportunity: Biochar can safely and efficiently sequester carbon in stable soil sinks, alleviating GHG emissions associated with the decomposition of waste from urban and rural sources (e.g. from land clearing or burning of agricultural waste).

2. Energy

The Opportunity: The pyrolysis that produces biochar also produces gas and oil which can be used as a low-carbon to carbon-neutral fuel in systems that provide heat, steam, cooling, drying, desalination, and more. For instance, bio-oil produced by pyrolysis can be used as a replacement for other fuels in engines and wind turbines (see here).

3. Heavy Industry

The Opportunity: Biochar and other end-products of pyrolysis can be used in the production of carbon negative thermoplastics (see Made of Air’s work) and lower-chemical fertilizers. It also has use cases in water filtration, e.g. using biochar to ‘bind’ and remove pesticides, pharmaceuticals, and fuel compounds from water (see here). 

4. Built Environment

The Opportunity: Biochar shows promise as a less GHG-intensive construction material. It has successfully been tested as a replacement for cement-based composites, given it provides thermal insulation, has passive cooling properties and is lightweight. 

5. Food, Agriculture, and Land Use

The Opportunity: Biochar can help address global food security issues by improving soil infrastructure and crop productivity. Further, it can sequester carbon from waste products (e.g. trash or sewage sludge) that fill landfills and contaminate otherwise productive land. 

The Players

Biochar Producers and Suppliers

  • Carbo Culture: turning waste into functional biocarbons for carbon sequestration and urban water and tree management 
  • Carbofex: biochar production technology, equipment and facilities
  • Pacific Biochar: biochar manufacturer and distributor. Notably, Pacific Biochar was the first producer to secure carbon credits for biochar in the United States. 
  • Circle Carbon: biochar and biochar enriched soil producer (+ organic farming 🥕🥕)

Waste Management and Equipment

  • Tigercat Carbonator: a biochar conversion system for wood debris 
  • Aries Clean Technologies: systems for transforming biosolids from sewage and wood / other dense biomass into biochar
  • TakaChar: low-cost, portable equipment to convert biomass waste into solid fuel, fertilizer, and other specialty chemicals
  • AirBurners: ‘air curtain’ burning machines that burn wood without emitting GHGs
  • AgWaste Solutions: converting manure and agricultural wastes into renewable energy, clean water and fertilizer.
  • Advanced Biorefinery: systems for pyrolysis and biochar production
  • All Power Labs: biomass-powered generators

Soil Improvement, Gardening and Agriculture

  • Bio365: a wide variety of biochar-enriched soils tailored to different crops and plants 
  • Willow: DTC biochar-amended soil blends
  • Pure Life Carbon: soil mix and soil supplements to power plant growth 🌱
  • Carbon Gold: biochar-enriched compost 
  • LESCO CarbonPro: biochar soil amendment specifically for golf and turf ⛳
  • Climate robotics: robotics and automating processes that improve and promote the use of biochar in carbon sequestration and soil enrichment

Remediation and Water 💦 Treatment

  • Glanris: creating biocarbon from rice husks for water filtration
  • Ridge to Reefs: treating septic wastewater and water runoff using biochar
  • Bygen: conversion of waste products into activated carbon for soil remediation
  • Stormwater Biochar: removing metals from stormwater

Carbon Negative Materials and Sustainable Cities

  • Made of Air: turning wood waste into carbon negative thermoplastics
  • Stockholm Biochar Project: creating the first large scale biochar plant to manage the increasing amount of urban waste and build a cleaner city 
  • NPS: greener road surface installation 
  • Cast in Carbon: research on carbon-negative building materials, including biochar

Biofuel and Energy

  • Red Rock Biofuels: producing low carbon, renewable biofuels with proprietary gasification technology and wood waste
  • ICM Inc.: turning solid waste into energy with proprietary gasification technology 
  • AIREX Energy: technology as well as a commercial power plant to transform wood waste into renewable energy, biochar and other products
  • Rainbow Bee Eater: creating syngas and biochar production from waste biomass 
  • Ambient Energy: machines for turning feedstock waste into clean energy

Carbon Removal Marketplaces

  • Puro.earth: B2B carbon removal marketplace
  • Carbon Future: a platform for biochar carbon sink credits, each of which compensates for the emission of 1 ton of CO2
  • Nori: blockchain based carbon removal marketplace, used by companies like Shopify

Biochar Association Groups

Where It’s Headed 

As demand for carbon offsets grows, with more major corporations committing to carbon neutrality in the coming decades, the biochar market will grow, too. It’s estimated the global biochar market will reach $3.1 billion USD by 2025.

To support demand for carbon offsets, Biochar production will have to expand. The 2016 Billion-Ton Report by the U.S. Department of Energy concluded that the US alone has the potential to sustainably produce at least 1 billion dry tons of nonfood biomass resources annually by 2040.

Demand for carbon offsets will drive more capital investment and reduce the cost of biochar production, making other use cases more economically viable, e.g. energy, fuel, and larger scale use in soils (for more on this, see the Obstacles section of this report).

China has an important first-mover advantage in biochar production. Currently, China produces ~500,000 tons of biochar fertilizer each year across 60+ production plants. Given their head start and central decision making authority, it’s likely China will continue to outpace the rest of the world in biochar production.

Biochar will be key to building carbon negative cities. Cities are more agile first movers (as opposed to national or even international government entities) and will pilot the implementation and use of biochar to create carbon neutral or negative municipalities. Carbo Culture already offers ‘urban climate mitigation’ as a service.

Opportunities for Action 

Buy: Biochar as a carbon offset. Looking to offset your or your businesses’ (or your personal) carbon footprint? There’s plenty of marketplaces for that (see “Players – Carbon Removal Marketplaces” section of this report). Importantly, additional demand will incentivize more biochar production capacity. 


  • Running a business that creates biomass waste? Add pyrolysis to your post-production process to offset emissions and create valuable biochar. 
  • Or, if you’re looking to create a new venture, you could offer biochar production “as a service” for companies that have agricultural waste. 
  • Of course, this isn’t as simple as just buying your own pyrolysis machine. If you’re looking to go from 0 to 1 with a new biochar business, GECA is a reputable biochar consultancy. 

Bring biochar to your city: The Stockholm Biochar Project has produced a replication manual as a roadmap for global citizens to introduce similar projects in their own communities. 

Train: Take inspiration from Warm Heart, which provides local farmers in developing countries training on biochar production and utilization. This eliminates open field burning, replaces commercial fertilizers, and saves farmers money.  

Convert: Convert natural charcoal facilities into biochar facilities. Since charcoal and biochar are produced under similar conditions, there’s an entrepreneurial opportunity for charcoal producers to diversify their markets and benefit from demand for carbon offsets in the process. 

Bootstrap a production business: The biochar market is in very early stages of development. With demand for carbon credits and offsets growing rapidly, the market needs more producers. As a producer, you could sell offsets via marketplaces or via direct partnerships, too. Ready to make a difference and some 💰? 

Commercialize biochar additive animal feed: Biochar animal feed reduces methane emissions from animals by ~15-20%, and also improves weight gain and feed efficacy as well as overall health for the animals 🐄🐖🐔. This is a popular use case for biochar in Europe; yet, there’s an apparent market gap in the U.S. Who’s going to change that? 

Build a business and prevent forest fires? Smokey the 🐻 says “Do it”: Disconcerted by all the terrible wildfires in recent years? There’s an opportunity to create and operationalize mobile technologies that use pyrolysis for active forest management (controlled burning of biomass in forests), carbon sequestration, and biochar production. 

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Thanks to Peter Olivier from The Burning Question for helping us wrap our heads around critical obstacles facing the biochar market. 

There isn’t yet enough biochar production capacity installed. The supply side of the space can already barely keep up with growing demand for carbon offsets.

Why? The economics for biochar are only just now becoming sufficiently attractive. 

  • More lending and capital investment is needed to get more biochar projects financed. Banks and lenders meanwhile like to see a stable track-record of strong cash flows before lending. Those track-records take time to build. 
  • While demand for carbon offsets may help finance new production facilities, few biochar buyers rarely offer long-term offset agreements that would supply the visibility into future demand desired by banks and lenders to fund projects. 
  • In sum, there’s a bit of a chicken vs. egg problem 🥚 “…financing is THE obstacle to scale,” notes Peter. 

Soil-enhancement: Not all biochar is made equal. Biochar is not immediately beneficial to all soil if it is directly mixed in as a soil amendment. Different soils each benefit from different microbial solutions; successful integration of biochar into soils and compost requires time, testing, unique knowledge and experience. In worst case scenarios, integrating the wrong type and / or amount of biochar to soil can harm rather than help.For most farmers, especially large-scale operations, the time and capital investment required to successfully integrate biochar into their soil may well be prohibitive.  

Energy Production: Compared to other clean energy alternatives such as wind, solar, and nuclear, we believe that the primary utility of pyrolysis and biochar will be concentrated in capturing and storing carbon, less so in energy production. That said, they are promising alternatives for energy-intensive applications where battery-power isn’t yet an option, such as in planes, cargo ships, and rockets. 

Your Next Role 

Open Positions at: 

Interested in working in climate tech and not finding the perfect role above? Shoot us a note at [email protected] we’d love to help.

More to Explore 

The soil improvement benefits of biochar stem in part from synergies between biochar and mycorrhizal fungal hyphae. For more on mycelium and it’s importance as a climate solution, see Keep Cool Report #0001: Mycelium