Episode 3: Lean, Mean, Charring Machine
What the hell is H/C ratio?
Welcome back to the blog version of Grounded: A Climate Startup Journey. If you've been following our story, you'll know that I've dived headfirst into founding a biochar carbon removal business. In the last blog, we explored how Cornwall's rich agricultural landscape (and my family ties) could be the perfect setting for our pilot project. This time, we tackle the next big challenge: finding the right machine.
Chapter 1: The Quest for the ‘Perfect’ Machine
Starting a biochar business involves more than just enthusiasm and good intentions. One critical component is the pyrolysis machine—a piece of equipment that transforms organic material into biochar through high-temperature decomposition in the absence of oxygen.
A Range of Options
Pyrolysis machinery that meets our needs has been around in various forms for decades now, however I was struck by the staggering variety of kit available and the difficulty in actually finding them in the first place. From smaller units costing around £20,000 to industrial behemoths priced upwards of £2,000,000, the range was mind-boggling. Each machine offered different levels of automation, capacity, and efficiency…
DIY vs. High-Tech
Initially, I toyed with the idea of a DIY approach. My Carbon Removal Show co-host and friend Emily Swaddle had always been passionate about the simplicity of biochar production. She once described her dream setup to me: a small kiln in her back garden, turning organic waste into biochar for her veg patch (very Emily). Whilst charming and great for your at-home enthusiast, it wasn't practical for a commercial operation aimed at producing high-quality biochar and carbon credits. I had to think bigger!
Batch vs. Continuous Systems
One significant decision was choosing between batch and continuous pyrolysis systems. A continuous system operates like a conveyor belt, constantly processing material and producing biochar. It's efficient but costly and complex. In contrast, a batch system processes material in discrete loads, which is less efficient but more flexible and affordable.
Learning from the Pros
I sought advice from industry veterans like Rob Palmer, previously founder at Dark Black (another UK biochar startup). Rob's journey highlighted the challenges and rewards of large-scale biochar production. He had opted for a continuous system but faced numerous obstacles, from regulatory hurdles to operational costs. For me, his experience reinforced the importance of us starting small and scaling gradually. This meant opting for the batch approach.
Chapter 2: Meeting CapChar
During my search, I was introduced to Adam and Chintan from CapChar, a company dedicated to making decentralised biochar production accessible and economically viable. They proposed a batch machine designed to strike a balance between cost, efficiency, and flexibility.
CapChar's Approach
CapChar's system is a three-cubic-metre batch kiln that operates similarly to a wood stove. It starts by burning logs to generate heat, which then drives the pyrolysis process. The machine self-fuels using the syngas produced during pyrolysis, meaning we wouldn’t need electricity to run it. There’s naturally more complexity to this machine but it made sense to just give a high-level description here.
Affordability and Practicality
This machine, costing between £30,000 and £40,000, was within reach for our pilot project. It achieved the necessary temperatures for high-quality biochar (500 degrees celsius and upwards) and allowed for the flexibility to experiment with different feedstocks. Something that was critically important - this size of machinery and output didn’t require extensive permits or planning permission. In the UK you are able to produce biochar without a permit (which can take up to 18 months) if you meet the Environment Agencies Low Waste Risk Positions. More info here and here.
Chapter 3: Navigating Standards and Certifications
Producing biochar is only half the battle; selling carbon removal credits requires strict adherence to standards. Next on my ever growing checklist was to delve into the complexities of biochar certification. It turns out that different standards bodies have varying criteria.
The Challenge of Standards (for us)
Standards like the European Biochar Certificate (EBC) and Puro are the most well known for validating carbon removal biochar projects. However, when I delved into their methodologies, standards like these favoured continuous systems with sophisticated heat recovery processes—something our batch system might struggle with in the early days. Interestingly, standards were very geography specific. I discovered that if we were to put a batch system like CapChar’s in regions outside of Europe or North America we would have no issue in certifying our project. More on that later…
Seeking Expert Advice
To navigate these challenges, I consulted a bunch of experts and spoke to people like Garrett Guard from C-Capsule. He emphasised the importance of meeting specific metrics such as hydrogen-to-carbon (H/C) ratios and moisture content. While certification processes are time-consuming and costly, they are essential for market credibility.
Wait a minute… What the hell is H/C ratio? A fair question. It’s a measure of how much hydrogen there is compared to carbon in the biochar. It's important because it tells us about the stability and quality of the biochar. A lower H/C ratio (less than 0.7) means the biochar is more stable and won't break down easily, making it better for use in soils to improve their quality and help store carbon for a long time. This stability is crucial for ensuring the biochar effectively contributes to environmental benefits like carbon sequestration. It’s worth noting that based on test burns, biochar made from a CapChar machine was well below the required 0.7.
The Path Forward
Despite the hurdles, I was keen to see whether we could make it work with CapChar's system. Their approach aligned with our pilot ambitions of decentralised, farm-based biochar production. It was within budget and we could leverage their expertise. The risk we faced was that we might not be able to produce and certify carbon removal credits, even if the H/C ratio was low enough, given their machine did not fit neatly into the standards we were researching…
Optimistic Realist
Securing a partnership with a pyrolysis manufacturer would represent a significant step towards realising this little business idea of mine. Stay tuned for the next episode, where we'll get to with this. The journey is just beginning, and I’m excited to share every step with you.
If you want to listen to Episode 3, click the link below 👇👇
Thank you to the guests who featured in this episode, including:
Rob Palmer – Director of Innovation, UNDO
Chintan Mahida – Co-Founder, CapChar
Adam Samuel – Co-Founder, CapChar
Garrett Guard – Carbon Removal Methodology Specialist, C-Capsule
Emily Swaddle – Co-host, The Carbon Removal Show
Alex Hume – Senior Associate, Finance Earth