A Model for Circular and Sustainable Food Production: Localisation and Replication

December 8, 2021
UNDP South Africa

Food, energy and water are essential for human life and well being, and demand for all three will continue rising. Food, energy and water are interlinked and interdependent. To capture the complexity and dynamism of the system connections, a nexus approach is used, enabling a frame to unpack the interrelationships between our natural resources.

As UN Water notes, the water-food-energy nexus is central to sustainable development. As such, this is a key focus area of the United Nations Development Programme (UNDP) Accelerator Lab (AccLab) in South Africa, and within this, we have been exploring how to transform food systems (blog) to be resilient and sustainable. We implemented a year-long project on food waste with multiple interventions including surfacing and scaling local innovations, research and development, enterprise development, training, and conducting a behaviour change campaign. This work has been achieved through working with a portfolio of partners as well as building relationships with many actors in the broader ecosystem. This relationship development led me to a farm in Tongaat in the KwaZulu-Natal province to meet a local entrepreneur who I was told was doing something truly extraordinary.

It turns out he is, and this is the story of his innovation as he explained it to me.

Anban Pillay is a self-taught hydroponics, aquaponics, open-field, and livestock farmer. His passion for development and supporting youth drove him to set up his farm with almost no resources, using discarded materials and ingenuity to build a circular farming system. Not only is he using waste materials for infrastructure, but the farm is also centred on transforming food waste into a valuable resource. As our AccLab colleagues in North Macedonia captured it, “The distinction between ‘waste’ and ‘resource’ is often a matter of imagination”.

“We can create a system where food is grown for the community, by the community, in the community. Everything we do is small scale, but scalable.” – Anban Pillay

Let’s jump into this circular system with biochar. Using an old geyser as a kiln and upcycled toolboxes and steel for the chimney and other components, scrap wood is placed inside and is heated indirectly at temperatures ranging between 900 – 1100 degrees Celsius. The wood goes through a process of pyrolysis where the decomposition of components happens through these high temperatures. Water escapes as vapour, and then the oils in the wood are turned to gas through pressure, igniting and super-heating the chamber, and carbonising the timber.

Anban has had the resulting biochar tested at the Council for Scientific and Industrial Research (CSIR), and the results show 88.65% pure carbon which is very high. This carbon is also locked in and considered ‘captured’ and so contributes to fighting climate change. The wood is discarded scrap from palete manufacturers who would normally have to pay for the wood to be removed, at which point it would go to landfills and decompose. Besides being cleaner than charcoal due to the lack of oils, biochar is highly porous – biochar has a surface area of approximately 340 metres squared per ONE gram. This is the equivalent of about a 42 metre by 42-metre fields in just one teaspoon.

Now we have our biochar, we can move on to the chicken coop. Biochar is sterile, inert and acts as a detoxifier, and Anban applies it to the floor of the coop. This has resulted in less transfer of pests and disease, less odour, and a healthier environment overall. This step in the cycle serves to activate the biochar – the biochar captures the chicken excrement which includes ammonia and nitrogen.

The chickens also eat the biochar which improves their digestive health, and this has had a notable impact on the food to weight conversion. Boiler chickens mature in 6 weeks, and this small chicken coop can produce 100 chickens per week. This produces an earning potential above minimum wage, and even above the living wage which is more than double the current minimum wage. And as Anban calls it, these are “carbon-offset chickens”.

We now move on to the worm farm which is housed in a recycled bathtub. These worms feed on food waste and produce ‘castings’ which is an incredibly nutritious fertilizer. These castings can also be converted into ‘worm tea’, creating a liquid fertilizer full of beneficial microbes. The biochar collected from the chicken coops is soaked in this worm tea, and the porosity of the biochar creates a perfect home for the microbes to multiply and flourish. In addition, the chicken excrement provides food for the microbes ensuring maximum multiplication and health. We are now left with biochar that has been ‘super charged’ with worm tea, which boosts microbiological activity in the soil by adding bacteria, fungi, actinomycetes, and protozoa, acting as a natural fungicide, insecticide and fertilizer. This is then used in open field farming, with only one ton per hectare producing a substantial impact on plant growth and health.

This supercharged biochar is not only used in the chicken coop, but also the aquaponics system. Aquaponics is the farming of fish along with plants in a soil-ess environment, and this system in itself is circular. Fish are kept in one container in constantly flowing water; the fish excrement creates high levels of ammonia in the water which then flows into a biofilter; the biofilter contains microbes which convert the ammonia to nitrite and then to nitrates; this water then flows into a container where plants are growing floating on the surface, and the nitrates provide a highly nutritious feed source for the plants; finally, by absorbing these nutrients through their roots, the plants clean the water which then flows back into the fish container. And what better biofilter to use than supercharged biochar.

An overview of the aquaponics cycle

These freshwater fish provide an alternative protein source to livestock where livestock farming, and the production of their feed, contributes a huge amount to climate change.  Anban has noted that the vegetables grown in an aquaponic system have a two to three week longer shelf life than other vegetables. This is because the plants receive a full spectrum of nutrients through this process, as opposed to the very specific nutrient profiles that are available in chemical fertilizers. Using biochar thus also assists in transforming farming systems to organic and so assists in getting certification for organic farming much more quickly.

There are also additional feedback loops in this system to deal with any deficiency or excess as it arises. For example, excess composting worms are fed to the chickens, any uneaten fish food gets syphoned off and fed to the composting worms, and chicken droppings can be fed directly to the fish.

“I like to try and figure out what happens in nature. For example, with tunnel farming, you are manipulating nature to create the perfect growing environment. What we are doing here is simulating what happens in nature” – Anban Pillay

(We strongly support this approach, and you can see this blog on AccLab's biomimicry project)

We’re now moving into the final loop in this system – black soldier flies. In an upcycled shipping container Anban has set up a black soldier fly operation using a broken refrigerator, old ice cream containers, waste coffee sticks, and some netting. Simply, the flies lay eggs, the eggs become larvae, and the larvae are fed food waste until they grow and are harvested. One fly lays between 700 – 1200 eggs, they hatch within a few days, and the larvae are harvested when they are 5 days old. 10 000 larvae will eat 15 kilograms of food waste over a 15 to 18 day period – as Anban says, “they are nature’s trash compactors”. The larvae are dried and powdered, and are an extremely nutritious feed source for livestock, with high levels of protein and containing a full amino acid profile. The system in this one shipping container can produce 400 kilograms of larvae per day.

“We can only solve the economic crisis we are in by creating entrepreneurs”, he shared.

The final and most important ingredient in this system is supporting unemployed youth. During the COVID-19 pandemic, Anban entered into a collaboration with a homeless shelter in the nearest city which was did not have enough space due to the impacts of COVID-19. He invited youth to stay on the farm and learn how to manage and run each of the solutions, capacitating them to become emerging farmer entrepreneurs. The farm has become a living training ground, where youth can go through an internship programme for over a year and then move into roles taking on more responsibility. Anban has a strong belief in the power of experiential learning: “Agriculture is sensory; for example, when you do aquaculture, you learn how to feel the water – clean water and dirty water feel different. You learn what your pump sounds like when it is creating trouble, and so on”, he said.

Moving forward, Anban is creating a model for entrepreneurs for each solution in this system. In that way, he can overcome the challenges often seen in cooperatives such as competition and ownership, and create a “cooperative of cooperatives”, where each entrepreneur is responsible for a certain element and holds a stand-alone business, but each contributes and feeds into the other businesses.

“I have no one favourite solution [on the farm] because it all just works together” – Youth Entrepreneur

By designing solutions with low-cost infrastructure and workable business models, Anban can give youth entrepreneurs a replicable business that they are trained to run and manage. Supporting and bringing together a cohort of emerging farmers additionally means that they begin to have bargaining power and can get better prices for any equipment or supplies they need. By using these innovative techniques, it is also addressing the challenge of youth moving away from agriculture as they see it as the ‘old way’ of doing things. And by replicating these local and interlinked solutions, this work contributes to multiple Sustainable Development Goals (SDGs) such as decent work and economic growth, zero-hunger, responsible consumption and production, and climate action.

If you would like to know more about this work, or are interested in collaborating in this thematic area, please reach out to me at simone.smit@undp.org.