Store CO2 in the soil with plant carbon
Farmers should char plant residues and use them as soil conditioners. This increases the fertility of the soil and permanently stores carbon in the soil. Two SMEs present their prototypes of charring plants, which are intended to meet the needs of Swiss agriculture.
A barrel with a chimney - that's what the prototype looks like with which André Van der Veken wants to revolutionize Swiss agriculture. "It's not pretty, but it works," says the founder of the company Carboforce proud. The barrel's inner workings are a lot more complex than they look. It is a highly modern furnace that chars mixed plant waste without oxygen and produces hardly any exhaust gases.
The process is called pyrolysis and is currently experiencing a major boom in the field of vegetable carbon. The aim of André Van der Veken and his company Carboforce is to develop a cost-effective pyrolysis plant for farms. The task now is to simplify the handling of the prototype and to design a housing that replaces the barrel as the shell of the furnace. The SME in Cernier, Neuchâtel, is receiving financial support from the Climate Foundation Switzerland.
Triple use
Vegetable carbon is porous like a sponge. It is not burned. Instead, it finds multiple uses in agriculture: First, farmers mix vegetable charcoal into animal feed - this makes it easier for the animals to digest. Second, charcoal is added to barn bedding and manure to reduce ammonia and methane gas leakage. Third, plant charcoal is plowed into the soil, allowing the soil to absorb more water and nutrients.
Carbonaceous soil is very fertile and was already known to the indigenous people in the Amazon region over 1000 years ago. They were able to significantly increase their yields thanks to the so-called "Terra Preta". In some African countries, coal is still successfully used today as a soil conditioner.
Old knowledge rediscovered
The Western world is rediscovering coal along with the modern pyrolysis process. Universities around the world are researching the topic of vegetable charcoal, or "biochar" in English. In the state of Oregon in the USA, a four-day biochar conference starts on August 22. In October, the third Asia-Pacific Biochar Conference is already planned in South Korea.
Research, development and agriculture are also networking in Switzerland. Eco center in Langenbruck founded the "CharNet", a network of stakeholders active in the field of vegetable carbon. The Federal Offices for Agriculture and Environment are planning a round table with knowledge holders on the topic in September 2016.
Back in 2010, the Biochar Science Netwok was founded by the Delinat Institute in Valais and the University of Zurich. Other universities and research institutes in Europe have joined the network. The network has played a key role in establishing guidelines for the quality of biochar in Europe. Quality assurance is therefore one of the main topics in the discussion on vegetable carbon in Switzerland. Other focal points are the launch of new research projects and the licensing practice for the use of vegetable carbon in agriculture.
Opportunity for climate protection and the economy
The Swiss Climate Foundation supports SMEs that do something for climate protection. For the past five years, this has included projects in the field of vegetable carbon. In the Zug mountain region, for example, several farmers have joined forces to produce vegetable charcoal in a larger plant. The foundation contributed to the investment.
"Producing vegetable charcoal on your own farm is still too expensive for many farmers," says Vincent Eckert, executive director of the foundation. The demand for good and cost-effective plants is high, he says. The Swiss Climate Foundation therefore also supports Swiss SMEs that develop pyrolysis plants. The foundation is a voluntary initiative of renowned service companies in Switzerland and Liechtenstein. Its aim is to promote climate protection and strengthen the domestic economy at the same time.
Production directly on the farm
For Swiss agriculture, smaller equipment is needed than abroad, so that vegetable carbon can be produced directly on farms in a decentralized manner. In addition to Carboforce by André Van der Veken, the Swiss Climate Foundation also supports the company Cascade-E in Basel in the development of a prototype for farms.
Business manager Stephan Gutzwiller has already been selling small pyrolysis devices for hobby use for several years. Now he has bigger plans: "My vision is that every Swiss farm will produce its own vegetable charcoal," he says. His prototype is connected to a heat exchanger that harnesses the waste heat from charcoal production for heating. An extension that is also planned for the Carboforce project. Stephan Gutzwiller of Kaskad-E is now looking for a farm to test his prototype under real conditions.
Soil as a carbon store
The Swiss Climate Foundation sees great potential in plant charcoal for the fight against climate change. "Soil is the largest carbon store on earth and therefore a very important factor in climate protection," explains Vincent Eckert. But with climate change, the soil is also changing. The humus layer decreases, carbon escapes and the soil can store less water. Vegetable carbon counteracts these trends. "Some of the carbon that the plants have filtered from the air remains bound and can be permanently stored in the soil," says Vincent Eckert, adding, "At the same time, the soil's ability to absorb water and nutrients improves, which brings direct benefits to farmers."
(Text: Climate Foundation Switzerland)
