Biochar Beyond Agriculture: How Biochar is Making a Difference Across Industries
Biochar is increasingly recognised for its versatility beyond its well-documented agricultural uses. in the UK and beyond are now exploring its potential to address sustainability challenges in construction, wastewater treatment, urban landscaping, and more.
Biochar’s extensive surface area and high porosity make it a great water adsorbent and wastewater treatment. Findings have also shown that adding biochar in concrete production can help to reduce the greenhouse gas emissions over the lifecycle of the product. This could make a big dent in global emissions as the construction sector accounts for nearly 40% of global energy-related carbon emissions. All of these highlight biochar’s adaptability, though many applications remain in early stages, requiring further research to assess scalability and long-term viability.
The UK’s net zero strategy references biochar as part of broader decarbonisation efforts, but its industrial adoption remains experimental. By examining these emerging uses, this blog post aims to shed light on biochar’s evolving role in sustainability across different industries.
1. Biochar in Construction
The construction industry, responsible for nearly 40% of global energy-related carbon emissions, is under increasing pressure to adopt sustainable practices. Biochar is emerging as a transformative material in this sector, offering solutions to reduce emissions, enhance material performance, and repurpose organic waste.
Enhancing Concrete Performance
Biochar’s integration into concrete is one of its most promising applications. By replacing a portion of cement or aggregates, biochar reduces the carbon footprint of concrete production while improving mechanical properties. For example, adding 2% biochar to 3D-printable concrete increased its structural build-up rate by 22% and reduced its carbon footprint by 8.3%. Similarly, substituting 10% of cement with biochar in mortar boosted compressive strength by 24.2% while sequestering 6% of CO₂.
3D concrete printing (3DCP) is a revolutionary technology that reduces labour costs and material waste. Biochar’s role in this field is gaining traction - Biochar-augmented 3D-printable concrete demonstrated enhanced pumpability and extrudability, critical for large-scale construction projects.
Beyond structural applications, biochar is being tested as an insulation material. Its low thermal conductivity (0.08 - 0.2 W/m·K) makes it ideal for reducing energy consumption in buildings. Biochar-infused insulation can lower heating and cooling demands, potentially saving 59 - 65 kg of CO₂ per tonne of material used. Its porous structure allows biochar to absorb and release moisture, improving indoor air quality and reducing mould risks.
These advancements are supported by UK-led research, such as Heriot-Watt University’s £800,000 project, which aims to develop biochar-enhanced building materials and assess their real-world performance. Similarly, the Mersey Biochar facility in Warrington is exploring biochar’s dual role in carbon capture and low-carbon heat generation for buildings.
2. Biochar in Wastewater Treatment
Wastewater treatment faces mounting challenges globally, from heavy metal contamination to microplastics and nutrient pollution. Traditional methods often rely on energy-intensive processes or chemical treatments, which can generate secondary pollutants.
Biochar’s unique physicochemical properties - high porosity, expansive surface area, and tunable functional groups - are positioning it as a sustainable alternative for addressing these issues. In the UK, pilot projects and research initiatives are exploring its potential to transform wastewater management while aligning with decarbonisation goals.
Biochar’s effectiveness in wastewater treatment stems from its ability to adsorb, filter, and immobilise pollutants through multiple mechanisms. Its porous structure traps contaminants like heavy metals (e.g., arsenic, lead) and organic compounds via physical adsorption and chemical interactions such as electrostatic attraction or ion exchange.
Also, biochar acts as a permeable barrier in filtration systems, capturing suspended solids and microplastics (MPs) as water passes through.
Engineered biochar, such as magnetically modified or zirconium-coated variants, enhances pollutant affinity. For example, zirconium-amended corncob biochar achieved 99% removal of arsenic in lab tests.
Biochar’s affinity for heavy metals is well-documented. A 2024 study demonstrated that magnetically modified biochar composites removed 81-99% of arsenic(III) and arsenic(V) from contaminated water, offering a low-cost solution for regions like South Asia, where arsenic poisoning is endemic. In the UK, modified biochar could address legacy industrial pollution in waterways, though scalability remains a hurdle.
Conventional treatment plants struggle to remove microplastics (MPs) and nanoplastics (NPs), which persist in aquatic ecosystems. Biochar’s high surface area and pore volume enable it to adsorb MPs/NPs effectively. Recent research highlights its potential in hybrid systems, such as coupling biochar with coagulation-flocculation processes to enhance removal efficiency.
In addition, biochar can recover nitrogen and phosphorus from agricultural runoff, reducing eutrophication risks. Pilot projects in the UK have integrated biochar into anaerobic digestion systems to capture nutrients from sewage sludge, which can then be repurposed as fertilisers - a process that aligns with circular economy principles. For example, Caradoc Charcoal explored biochar’s wastewater applications with support from Aston University’s Energy & Bioproducts Research Institute (EBRI). Their biochar, a byproduct of charcoal retort processes, demonstrated potential for filtering industrial effluents and improving water quality in local treatment systems.
3. Biochar in Energy
By converting biomass waste into energy-rich products, biochar is believed to offer an additional benefit of generating renewable energy. Biochar is being integrated into innovative energy systems, from biomass co-firing to advanced energy storage technologies in the UK.
It’s important to note that biochar production via pyrolysis generates not only solid carbon but also syngas and bio-oil, which can be harnessed for energy. Syngas, for instance, can fuel combined heat and power (CHP) systems. A UK demonstration plant by Coal Products Limited (now Invica Industries) uses syngas from biochar production to generate renewable heat and electricity, supporting grid decarbonisation.
Moreover, biochar can be blended with biomass in power plants to reduce reliance on coal. This approach cuts greenhouse gas emissions by up to 50% compared to conventional coal-fired plants. The Urban Biochar and Sustainable Materials Demonstrator in Birmingham exemplifies this synergy. By processing 3,000-5,000 tonnes of annual urban wood waste, the project produces biochar alongside syngas, which heats local horticultural polytunnels - a closed-loop system that reduces landfill waste and fossil fuel dependence.
Furthermore, functionalised biochar is gaining traction in energy storage due to its high surface area and electrical conductivity. A notable advancement is the engineered biochar materials. These are modified through chemical activation or heteroatom doping, and they exhibit enhanced energy storage capacity. Biochar-based supercapacitors, for instance, achieve energy densities comparable to conventional lithium-ion batteries, with the added benefit of sustainability.
4. Biochar in Urban Landscaping
Urban landscapes face unique challenges, from compacted soils to stormwater runoff and limited green space. Biochar is being tested as a potential solution to this. Once again, Birmingham’s Urban Biochar Demonstrator exemplifies how cities are integrating this material into green infrastructure projects.
Also, biochar’s porous structure and nutrient-retention properties make it ideal for urban tree planting and soil rehabilitation. Key applications include blending biochar with compost or macadam to improve soil structure, water retention, and microbial activity. In Stockholm, biochar-macadam mixes have been used since 2012 to support tree roots in hard-paved areas, reducing soil compaction and enhancing growth.
Similarly, Carbon Gold’s enriched biochar, infused with mycorrhizal fungi, revitalises ageing trees in urban settings. Trials in London parks show improved nutrient uptake and resilience to pollution, helping historic trees thrive despite urban stressors.
5. Biochar in Carbon Markets
As global efforts to achieve net zero intensify, carbon markets have emerged as a critical mechanism for incentivising climate action. Biochar, recognised by the IPCC as a carbon dioxide removal (CDR) technology, is increasingly positioned as a scalable and cost-effective solution within these markets. In 2023, biochar accounted for 94% of delivered carbon removal credits, underscoring its dominance in voluntary carbon markets.
Each tonne of biochar sequesters 2.5 to 3.0 tonnes of CO2 equivalent, depending on feedstock and pyrolysis conditions. This provides an avenue for companies to purchase biochar credits to offset their emissions. For example, airlines and tech firms are investing in biochar projects to meet net zero targets.
In addition, the UK’s Environmental Land Management Scheme (ELMS) now considers biochar as a qualifying practice for farmer subsidies, aligning agricultural policy with carbon market incentives.
Conclusion
Biochar’s potential to address sustainability challenges across industries is supported by growing research and pilot projects, though its scalability and long-term efficacy remain under scrutiny. In construction, wastewater treatment, energy production, urban landscaping, and carbon markets, biochar has demonstrated measurable benefits, such as reducing concrete’s carbon footprint by 8.3% in UK trials and sequestering 2.0-3.0 tonnes of CO₂-equivalent per tonne of biochar.
However, challenges persist. Production costs, feedstock availability, and inconsistent regulatory frameworks complicate large-scale adoption. For instance, biochar-amended soils in urban projects cost 20-40% more than conventional mixes, and only 1% of UK biochar production currently meets commercial demand. Furthermore, while biochar’s carbon sequestration durability is well-documented in lab settings, field studies, such as the University of Nottingham’s ongoing £4.5m trial, highlight uncertainties about degradation rates in diverse environmental conditions.
At Restord, we’re making biochar and exploring its real-world impact with UK farmers, businesses, and councils. Follow our journey on Grounded: A Climate Startup Journey, our award-winning podcast. Listen on Apple Podcasts and Spotify.
