The Biochar Solution
Carbon Farming and Climate Change
by Albert Bates
During our recent RegenAG course with Darren Doherty I had the opportunity to browse through a selection of permaculture-related books set up as a temporary library by the course attendees. One of the books there was ‘The Biochar Solution’ by Albert Bates. After reading a few randomly selected pages that mentioned topics that have interested me for years, such as ‘The Sahara Forest’, ‘Biochar Stoves’, and ‘The Groasis’ I put the book on ‘to read’ list and ordered it when I returned home.
Although the main topic of this book is biochar, Bates presents an excellent overview of the severe problems caused by our ‘conventional’ agriculture industry and the proven alternatives that can and do move large quantities of carbon from the atmosphere and into the soil. Indeed the subtitle of this book is ‘Carbon Farming and Climate Change’.
Bates discusses the history of biochar with tales of Spanish conquistadors in south America, huge cities along the Amazon river and fertile settlements within the rainforest thanks to terra preta (black earth) soils created by the native Americans. These carbon-rich soils could be farmed continuously, unlike the poor thin naturally-occurring soils found under tropical rainforests. It is now thought that the population of south America could have numbered not just in the tens of millions, but in the hundreds of millions before the Spanish conquest. European diseases such as Smallpox destroyed these societies following the arrival of the Europeans, killing perhaps ninety per cent of the people. The wood built cities vanished as the rainforest returned. The growth of this secondary forest was so vigorous that the transfer of carbon from the atmosphere to the new vegetation that it is now theorised that this could have caused the Medieval ‘Little Ice Age’.
The environmental community has seriously criticised, and rightly so, the inappropriate use of biochar as a tool for tackling climate change. Ideas such as charring virgin rainforest on a grand scale with the involvement of mega-corporations making big money out of the emerging carbon markets would be an environmental disaster. Bates tackles this and a whole range of other potential problems in his chapter “The Biochar Critique”.
The book focusses not on huge mega-projects by the mega-rich but on the application of biochar by the very poor to improve their lives while sequestering carbon. My favourite chapter in the book is ‘Stove Wars’ in which Bates describes the various biochar producing stoves that can be used by people in the Global south to cook with using waste biomass material. This is material such as crop residue which they would often just burn in the field. Using biomass stoves this residue is pyrolised. The gases given off in this process are burned to cook with and perhaps fifty per cent of the carbon that was contained in the crop waste is transformed into biochar. Thus the use of a biochar stove not only creates a product out of a waste stream, but also protects the trees that would have otherwise been cut down to use as cooking fuel. This biochar can be added to ground straight away where it will add nutrients, particularly nitrogen (which is often lost to the atmosphere in open fires in the form of the potent greenhouse gas nitrogen dioxide). However using one of the tenant principles of permaculture biochar offers many yields. Just like charcoal, it can be used to filter and purify drinking water. Without the biochar this water would either be drank dirty with serious health risks, or boiled – using still more wood. But even after being used to purify water the biochar has another use – it can be used as a base material and a cover material in a compost toilet. The resulting humanure/biochar mix can then be used to fertilise tree crops.
Bates describes a fantastic biochar producing stove called the Lucia WorldStove created by Nathaniel Mulcahy. WorldStove have created a business model whereby they do not sell their stoves in Africa, but rather help local people produce their own stoves. This vastly reduces costs and means the end users are far less reliant on outside aid.
Bates ends his book with a chapter called ‘Carbon Negative Communities’ in which he describes how we can go way beyond ‘sustainability’ and aiming for ‘carbon neutrality. It is within our power to sequester far more carbon than we produce, and this we MUST do.
I highly recommend this book to anyone with an interest in finding solutions to climate change. It is an upbeat book full of good news and solutions. We can turn this situation around. We are not beaten yet.