Biochar technology is gaining traction on hopes it can improve crop yields, sequester carbon, and boost soil lifecycles.
But there are question marks associated with scaling biochar production. Securing a consistent and competitively priced supply of biomass is difficult, while scaling up requires specialised equipment and training, which can be costly and time-consuming to implement.
Research and verification gaps remain, as do regulatory and policy hurdles. Determining the quantity of biochar in soils is also complex, time-consuming, and expensive, making verification for carbon trading challenging.
But UK-based start-up CapChar is confident that biochar is set to transform and decarbonise agriculture. Biochar has the potential to lock away CO₂ in soil for hundreds, even thousands, of years, it recently told a BBC Panorama documentary. When added to soil, it says, it fosters topsoil regeneration to enhance both water capacity and nutrient retention.
The company has developed a circular biochar solution which is says addresses the need for scalable, low capex technology, local carbon sequestration solutions that start working to reduce carbon emissions with no further delay.
The UK’s first on-farm biochar solution
Despite accounting for 89% of global voluntary carbon removals, biochar production in the UK remains limited. The idea behind CapChar’s ‘plug and play’ solution is to bridge this gap by supplying kilns direct to farmers so they can make their own biochar.
The farmer has the option to use the biochar they’ve produced on-farm to mitigate manure emissions and improve their soil.
Alternatively, they can use it to create carbon credits (which CapChar calls biochar carbon units) that are sold by CapChar on the farmers’ behalf to companies and individuals who want to offset their emissions.
The plan promises to create a new carbon economy for the UK by making biochar production accessible on-farm, says CapChar’s co-founder Adam Samuel. “Our vision is to empower the farming community to build a network of biochar plants which embeds local carbon sequestration, creates jobs, and new carbon revenue streams – key to achieving a sustainable agricultural system.”
He says the company hopes to build a decentralised network like that of anaerobic digestion plants, with thousands of plants across the UK where biochar is produced locally to grow a circular carbon economy providing rural employment and mitigate climate change nationally.
Reality check
A recent study by the Massachusetts Institute of Technology has showed that assumptions as to how much CO2 could be removed by direct air capture (DAC) technology are unrealistic in terms of quantity and cost to deploy. Samuel therefore believes the time is ripe for CapChar’s method. “The removal of emissions is necessary to offset both past and present emissions, especially as society continues to burn fossil fuels unabated,” he insists.
“We believe pyrolysis and biochar to be the most cost-effective form of carbon removal at present and one which can be deployed quickly at scale, today.”
CapChar claims that in addition to CO₂ removal, biochar works to reduce more potent GHG emissions including methane emissions when incorporated into cattle feed, ammonia from manure, and nitrous oxide from synthetic fertiliser reductions – providing a sustainable solution to decarbonisation. Studies have, however, found that biochar is ineffective as a feed additive for reducing methane in dairy cows.
One feather in the biochar sector’s cap is support from the Intergovernmental Panel on Climate Change (IPCC), which recognises biochar as an important carbon removal technology that can potentially remove up to 2.6 billion tonnes of CO2 per year.
“The IPCC’s support of pyrolysis as a negative emissions technology underpins support for the effectiveness of biochar to mitigate climate change,” says Samuel. Within agriculture, biochar is a good fit, particularly in mitigating emissions from manure, he says.
But he admits that adoption of biochar at scale faces challenges from availability of organic material, education in its usage and understanding of its benefits.
These challenges have clear solutions, he believes. “A simple first step would be to divert wood destined for biomass plants to biochar production. Instead of burning wood to ash for electricity generation, we could instead produce biochar and utilise the excess heat derived from the pyrolysis process to reduce rural energy emissions.”
Biochar, he insists, offers “so much more” in terms of emissions reductions from decomposition, reduced synthetic fertiliser usage, energy production and livestock emissions. Over 50% of UK woodlands remain unmanaged, he points out. “By supporting forestry and woodland training and management, we could revitalise a UK rural economy which offers much needed local employment in the provision of the feedstock for a biochar industry.”
A vision for policy support and sector transformation
And with the UK government set to introduce a carbon tax on fertilisers by 2027, CapChar is urging policymakers to follow Denmark’s lead by implementing financial measures to incentivise farmers to adopt UK biochar.
“The benefits of biochar are clear, with a future tax on synthetic fertiliser adding to agricultural input costs, the opportunity to produce biochar on-farm as an organic slow-release fertiliser saving bottom line costs is attractive,” says Samuel.
“As our climate changes, the need to safeguard food security means biochar has a key role to play in regenerating depleted soils while mitigating flood water and nutrient runoff longer term,” he says. “As more studies of biochar are undertaken, we are finding more use cases for this remarkably simple material which should ensure the value and demand for biochar as a raw material continues to grow.”
