On the outskirts of Kabati town, 14 kilometre from Thika town, smoke rises from metal kilns, not the choking haze of pollution, but the quiet breath of innovation. Inside these furnaces, waste wood and macadamia husks are reborn as biochar, a fine, carbon-rich material that promises to heal both the planet and the soil beneath Kenyan farmers’ feet.
At the heart of this revolution is Bio-Logical Green, a young climate-tech company co-founded by Philip Hunter and Rory Buckworth, whose mission is as ambitious as it is urgent: fighting climate change on a global scale while building resilience among Kenya’s smallholder farmers.
“Kenyan farmers are some of the worst affected people in the world when it comes to climate change,” Buckworth says. “And yet they have done nothing to cause it.”
Bio-Logical’s answer to that injustice is biochar carbon removal. The process begins with waste biomass – wood from eucalyptus processing, Mathenge tree and macadamia husk left behind after pulp extraction. Instead of burning or dumping this waste, the company feeds it into high-temperature pyrolysis kilns.
“We heat the biomass to about 350 degrees,” Buckworth explains. “That releases carbon monoxide and methane, which we reuse to fuel the process. The result is a stable form of carbon called biochar, which can lock up carbon for up 1000 years.”
Once cooled, crushed, and blended with compost manure, the biochar becomes an organic fertilizer sold to smallholder farmers at subsidized rates, thanks to proceeds from Bio-Logical’s carbon credit sales.
The impact is two-fold: carbon is sequestered underground, and soil health is dramatically improved.
“Biochar balances soil pH, boosts water retention, and enhances microbial life,” Buckworth says. “Farmers see better yields and more resilient crops, even in harsh conditions.”
Behind the quiet hum of the kilns is an intricate supply chain. Waste is aggregated from timber mills and fruit processors across the region, providing a steady stream of raw material and an income for local suppliers.
Each kiln processes about a tonne of biomass per cycle, producing biochar after roughly 10 hours. Once quenched, crushed, and mixed with compost, the material becomes part of Bio-Logical’s organic fertilizer, Asili, a product now spreading steadily across Kenya’s farms.
“Farmers are naturally cautious about new products,” Buckworth admits. “They don’t have the luxury of experimenting too much. That’s why we do field demonstrations and work with partner organizations to prove that our solution actually works.”
Beatrice Nyambura, a farmer in Kandara has been using Asili fertilizer for the past two years. She attests that since she switched from chemical fertilizers, she has seen significant increase in maize and vegetables production in her farm.
Two years since beginning operations, the company sells around 5,000 bags of fertilizer per month. Demand is rising as farmers see results that include improved soil structure, higher yields, and reduced dependency on expensive synthetic fertilizers.
Healing the soil from the inside out
For George Kamunya, Bio-Logical’s Head of Commercial, the company’s work is about more than just products. It is more about restoring a broken ecosystem.
“We want to empower and uplift smallholder farmers,” Kamunya says. “That starts with bringing down the cost of production, and the biggest cost for most farmers is fertilizer.”
Kamunya paints a vivid picture of what is at stake. “30 years ago, you would find worms and healthy bacteria in most farm soil,” he says. “Today, those worms are gone because we have interfered with the ecosystem of the soil, killing the good bacteria and worms mainly because of overuse of chemical fertilizers.
“Number two, we have overlooked the element of organic matter in our soils. Organic matter provides a very good home for good bacteria and living organisms that are beneficial to both the soil and the crop. Lack of organic matter interferes with the soil structure, which in turn leads to depleted soil health and lowers the production of the crop in the long run.
“So ideally, the reason as to why we use biochar in the soil is because biochar tries to restore that and we charge that biochar with organic compost which again addresses the element of organic matter in the soil,” Kamunya explains.
Biochar, he further explains, is a kind of “biological charcoal” that helps restore that balance. Unlike ordinary charcoal, it is produced in a clean, controlled process that removes impurities and stabilizes carbon.
“I usually tell people: biochar is charcoal that has gone to school,” Kamunya laughs. “It’s high-quality, high-carbon, and environmentally friendly.”
The science is compelling. “Under a microscope, biochar’s porous structure looks like a honeycomb,” Kamunya describes. “This allows it to store water and nutrients, keeping them accessible to plant roots rather than letting them wash away or be leached. Its neutral pH helps correct Kenya’s increasingly acidic soils, making nutrients more available to crops.”
“A 50-kilo bag of chemical fertilizer, only about 30 kilos are usable by plants, and half of that gets leached away,” he says. “Biochar keeps the nutrients where the roots can reach them. It keeps crops greener for longer and greener means more photosynthesis, more food, and higher yields.”
Building a climate-resilient future
As the world searches for scalable climate solutions, Bio-Logical’s model stands out for combining carbon removal with social impact. Their facility in Kabati, which is Africa’s largest biochar plant, can produce up to 5,000 tonnes of biochar and 24,000 tonnes of compost annually. But that’s just the beginning.
“We want to expand to become the biggest biochar company in the world,” Buckworth says. “We’re planning new projects in southern Kenya near Magadi, and also in South Africa, Uganda, Tanzania, and Mozambique.”
Their goal? To sequester one million tonnes of CO₂ every year by 2030, while helping farmers across Africa restore degraded soils and increase yields sustainably.
Back at the Kabati factory site, a worker, lifts a handful of black, powdery biochar. It feels light almost weightless but the science behind it carries the weight of a promise that waste can become wealth, that soil can be reborn, and that Africa can lead the way in climate-smart innovation.
