Written Evidence submitted by The Carbon Free Group CIC (SH0075)


I am a director of The Carbon Free Group CIC Based in Kent. We are a group of professionals working in the field of low carbon technologies in the built environment including super-efficient buildings and rural sustainable land management practice. My name is Edmond Rube and I live near Dover.

The reason for this submission is to highlight the future role of biochar as a means to provide multiple benefits to soils, sustainability and net zero.

The goal of having sustainably managed soil by 2030 is a laudable aim but for a number of reasons, is a great challenge. We lack a unifying methodology, we haven’t started, except in very limited cases, modern intensive food production methods are antithetical to care of the soil. The process of recovery will take decades so now is a good time to start.

The natural variability of soils makes their health categorisation a real challenge but this could be addressed through the analysis of its general biodiversity and then observing any increase in that biodiversity and any other obvious signs of improving soil condition.

Current regulations clearly do not protect soil. The need for yield, favours fossil fuel intensive, chemical inputs which destroys the soil. Any scheme to reward producers and landowners must ensure there are no rewards for activities that degrade soils.

Producers are driven to compete to provide food which is cheap, this is a driver of the destruction of our soil. Reduce meat consumption, grow appropriate vegetables and grain in a mixed, regenerative farming model using nature’s predators for pest control, where possible. Invest in research in precision fermentation technology with the aim of providing high quality protein as an alternative to our reliance on meat. Reducing our reliance on meat would relieve the pressure on our soil.

Spreading sewage sludge on fields has been shown to damage soil microbial diversity, worms and soil structure. Micro plastic in sewage sludge is hazardous to soil life and is a legacy pollutant that is poisoning the land. We even import this material to spread on fields. If it were pyrolised some of the harm would be reduced but far better to fully remediate before spreading. If it must be done, then stringent standards should be applied.

As part of The Carbon Free Group’s work to support the move to Net Zero and sustainable living and climate change, a new enterprise has been set up to address the challenges that the rural sector face which include climate change, soil degradation, energy cost, business diversification and food production. The group is called RTAP, Rural Alliance Transition Partnership. RTAP has identified the use of biochar as being the most efficient method for drawing down and sequestering carbon from  the atmosphere. Biochar also has many additional benefits, it can offset fossil fuel use, improve permeability of soil to reduce flooding and erosion at the same time as improving water retention in droughts, binding nutrients in the grow zone thus protecting aquifers and watercourses from nutrient poisoning, it provides a matrix within the soil which allows for fungi and bacteria to thrive, which in turn supports greater biological activity, it improves gas exchange which is lacking in degraded soils, it has been shown to improve yields and reduce disease in crops.

As a feed supplement, biochar has been shown to improve health and wellbeing in all livestock and reduce methane emissions. Animal bedding with added biochar has been shown to reduce odour and pathogens as well as lowering emissions of ammonia and methane.

There are many additional benefit multipliers in the production of biochar, the principle one being the sequestration of Carbon Dioxide from the atmosphere. Because biochar is stable for possibly a thousand years and more, its use as a soil amendment means that the biomass converted to biochar does not decay and is therefore removed from the atmospheric carbon cycle, It is therefore the most accessible and cost effective method for slowing climate change. Significant quantities of methane which is a far more potent but shorter lived GHG is diverted to stable soil carbon through this process

Biochar is a powerful tool for the remediation of soil, water and air and will strongly bind most toxic substances within its microporous structure. 55% of land in England is classified as a Nitrate Vulnerable Zone. The cost of dealing with the consequences of this damage and its myriad impacts runs into billions. So as well as regenerating soil, biochar improves our ability to care for and manage the wider landscape, for example, as filtration beds to remove oils and other toxins from road runoff, protecting watercourses and groundwater.

The addition of biochar to tarmac has been shown to enhance tarmac’s properties and extend its lifetime.

Biochar is easily scalable, it can be produced in many different ways, in expensive immovable plant or on a patch of open land with the feedstock being twigs, branches, brash, wood chip, corn husk and even grass clippings.

Biochar produces heat which can be used to heat buildings or generate electricity etc, avoiding fossil fuels.

As a community activity, there would be great potential for volunteers to run the production of their own locally collected biomass as many people would embrace the opportunity to offset their carbon emissions as a community good. The biochar could be sold to any number of end users, benefitting the community. This activity must always serve nature and the land and not be beholden to monetary  or  other unrelated aims otherwise the rationale may become distorted and the original goals can be missed. 

The Carbon Free Group has developed a biochar kiln that can produce significant volumes of biochar continuously and at low cost. It can run 24/7 but needs manning by ideally two people. At a cost under £20,000 the estimated carbon sequestration potential per year/ per kiln, is around two thousand five hundred metric tonnes. The kiln can be easily transported.

The biomass to produce the biochar could be collected and dried throughout the year and burnt in the winter when heat energy is required and the risk of fire reduced.

Ash dieback and other diseases have left many woodlands with much biomass that could be converted to biochar. Land cleared for development often has large quantities of biomass which is burned in order to dispose of it. In a more joined up system this “waste” could be converted to biochar. “Waste” from gardens that would usually be burnt on a bonfire could instead be part of the community biochar scheme. 

Tree planting using biochar has been shown to significantly improve the growth rate, health and crucially, the survivability of saplings in the crucial early years when watering may not occur. The current ambition to plant vast numbers of trees will be more successful if biochar is utilised.  

With a suitable incentivisation program there would be a strong uptake of biochar production, councils could get involved and utilise the biochar to improve the health of street trees and public gardens. Using a mobile kiln, the production can be carried out efficiently and the biochar used on land where the biomass originates, reducing unnecessary transport. Councils, many of which have declared a Climate Emergency might support this activity and collate the calculated carbon sequestration to offset their own emissions.

In conclusion, biochar provides manifold benefits and is cheap and easy to produce and supports the goals of sustainability, net zero and long term soil health.

Accompanying this submission is a review of 26 meta-analyses of biochar   


February 2023