For gardeners and everyone interested in climate change mitigation. It looks as if we could improve our soil and lock away carbon to reduce climate change – the heat can also be used, hence the carbon-negative cooking that James Greyson has been doing. If the gases are just allowed to escape, they add methane to the air, which is a serious climate warmer.

There’s an opportunity now to start testing the effects of the biochar on our gardens – there are instructions on the website.