Biochar – putting the carbon back

A new material to improve soil and help the environment. Pioneering techniques are being trialled to produce a carbon-rich kind of ‘charcoal’ from natural waste, plants and wood. Biochar will improve soil, increasing its ability to retain carbon, water and nutrients.

Benefits: better soil, less need for chemical fertilisers, fewer carbon emissions, value from unused products.

Traditional charcoal is produced from wood through a process which loses 50-70% of the original material. Biochar is produced using new techniques. As well as producing this valuable black, carbon-rich material, there are also valuable by-products, including oil, gas and heat.

IBERS has been given a Welsh Government grant to improve ways of producing biochar – using a variety of grasses, organic waste and wood – and to test the value of biochar in retaining carbon, improving the soil and boosting the growth of plants.

A special production facility has been designed and built to ‘burn’ materials without oxygen through a process called pyrolysis. Using combined heat and power technology, any gases and heat created are also used to produce other materials, such as bio-oil.

The big picture: The biochar project is part of IBERS wider research into improving the use of plant and organic ‘waste’. This is called biorefining. Through pyrolysis, much of this material may be converted into new products that can be used to produce more and better biomass, so creating a virtuous circle.