It was lovely to have so many people and some new faces at the Sustainable Marlborough Sustainable Social in March. Luke, a local sustainable charcoal producer who currently holds a Nuffield Farming Scholarship gave an incredibly interesting presentation on biochar, how it’s made and what you can use it for. His scholarship is taking him around the world to learn more about how biochar is being used so that he can bring ideas back to the UK. We loved that Luke is offsetting all of the carbon from his travels using biochar!
So, biochar is really very small pieces of charcoal, but it doesn’t have to be made from wood. Any biological matter can be made into charcoal including garden waste, animal bones and sewage sludge, but the carbon content will vary from 30-90%. 1g of biochar has a surface area of 300m2, so it’s incredibly porous and absorbs nutrients and toxins. Biochar has been found in 2.5 thousand year old Amazonian soil and certainly added to the fertility of the earth. Find out more here.
We learned about the many and varied uses of biochar, from adding it to animal feed to reduce methane, absorbing ammonia from manures, remediating soil pollution, water and air filtration, adding to tarmac to sequester carbon and strengthening concrete. The really great thing that we learned though, was that biochar can be added to compost bins to supercharge your compost and reduce the methane. By mixing the biochar with food waste (or manure), you charge it with nutrients, this is important as you don’t want the biochar absorbing the nutrients from your soil. The result is a lovely dark compost that retains water and nutrients.
After Luke’s presentation there were lots of questions and we discussed how biochar can be used for tree planting and could potentially be brilliant in Rain Garden planters to help slow the flow of rainwater and filter it at the same time, so great for local projects.
Judy also told us about Citizen Climate Lobby’s local meetings for the global movement pushing for a carbon tax and dividend. Meetings on 19th April, 17th May and 21st June.
Email judy@citizensclimatelobby.uk to find out more.
Slate Hill Charcoal’s biochar is a by product of their charcoal production for which they use a charcoal retort, which is really clean burning and recaptures most of the gases produced. The slow pyrolosis takes 6-8 hours. Luke and Helen source all of their wood locally where trees have been cut back or felled through responsible woodland management, so the carbon footprint of transportation is kept to a minimum. They’re always happy to receive visitors, so if you’d like to go and see Luke and Helen making their charcoal in Baydon, email hello@slatehillcharcoal.co.uk.
Marlborough Rugby – Victory over Chippenham is first step on ladder to Twickenham
