The future starts with the dirt beneath our feet. Soil is the earth’s fragile skin that anchors all life. However, half of the topsoil on the planet has been lost in the last 150 years. Soil restoration is a major concern of farmers and of all of us who depend on vegetation.
Soil restoration using Biochar (as with Terra Preta), is carbon negative by sequestering the carbon in biomass for thousands of years. Biochar incorporated in soils offers numerous benefits, such as improved soil fertility, reduced need for fertilizer input, enhanced soil microbial life, ecological food production, comprehensive erosion control and flood water prevention through high water storage capacity and much more besides. Achim Ecker from ZEGG designs for-profit greenhouse gas drawdowns that can contribute to ecovillage financial success. His usual tools are waste remediation biomass-to-biochar systems with nutrient, probiotic, energy returns from carbon-capture in soils.
When, in 2013, the ZEGG community in Germany found itself in the struggle to retain the rights to their own sewage treatment and drinking water, Achim Ecker was looking for ways to reduce water consumption and reuse waste water. He started to work with the fascinating prospects that Terra Preta offer. Urine has the highest content of Nitrogen and Phosphorus (80% N and 50% P). So why waste carefully cleaned drinking water in a WC and destroy those nutrients in a sewage plant that are urgently needed elsewhere? Both Nitrogen and Phosphorus are valuable soil ingredients for plant growth and health. Peak Phosphorus is close. Nitrogen is taken out of the atmosphere in a technical process that uses a lot of energy.
Achim learned from an article from the Ithaca Institute how to produce Biochar from brush in a Kontiki kiln (http://www.ithaka-institut.org/en/ct/101-Kon-Tiki-flame-curtain-pyrolysis).
He installed waterless urinals and urine tanks where it is fermented. The urine is being pumped into a container and used to charge Biochar (hot quenching of coals with fermented urine) and the compost stacks.
Achim: “The fresh charcoal must first be “charged” by soaking the charcoal for 2 to 4 weeks in any liquid nutrient like urine or plant tea until the pores are full. Otherwise uncharged charcoal will deplete the soil of nutrients.”
With composted leaf earth, clay, Bokashi, grass clippings and charged Biochar, we set up a compost stack in layers and let it sit for a year. All ingredients should also go through the intestinal system of an earthworm.
His first experiments with Terra Preta substrata in the soil have been very promising. Terra Preta is not just a fertilizer, it builds permanent fertile soil and sequesters carbon.