Disrupting the carbon cycle, by way of carbonisation of biomass and sequestration of the resulting biochar into safe and beneficial uses goes well beyond horticultural use in soils.

There is a vast opportunity that can be seen as sequestration with benefits! A term to differentiate biochar from some of the other carbon removal options which do not provide any additional benefits beyond sequestration. 

With a market value of more than £20B, the non-soil application of biochar materials opens-up even more potential for carbon sequestration with benefits as such Biochar can be used as an additive in asphalt. 

o   Our customers include highways sub-contractors who have started mixing and applying carbon neutral road surface dressings. So, the use of biochar in tarmac within the UK is already happening and growing. Current projects we supply mainly work with up to 3%-5% by volume. 

o   Including biochar improves binder stickiness and low-temperature characteristics. This is now being used to modify asphalt binder and as a replacement for mineral filler materials in asphalt mixes. An addition of approximately 2-10% biochar is considered technically feasible. However, the dosage should be less than 10% by volume of the asphalt binder. 

o   Biochar incorporated into asphalt improves its properties: application of the biochar-treated asphalt. Biochar enhances asphalt product performance – which assists its resistance to aging, low-temperature winter cracking and rutting in summer heat and wear. Also including porosity and run off from excessive rainfall.

o   Biochar slows down the aging of the asphalt material, so long-term durability, resistance to moisture damage, UV-radiation and fatigue create positive environmental and economic impact.

 o   Biochar with its naturally high carbon concentration provides stability and strength. In this process, 1% biochar was added to the surface layer and 5% each to the binder and base layers. The long-term behaviour of the asphalt surfaces under stress and weather conditions is commercially being tested by the wider industry.

Importantly, using biochar as an additive for asphalt is an “end of life” application. Meaning that it is a “final” application because the biochar is irreversibly bonded to the asphalt. Also in most cases, asphalt containing biochar is completely recyclable.