The circular economy is something I was happy to see feature heavily at GreenTech 2020. It seemed to be on everyone’s mind when discussing sustainability, and there was even a dedicated session on it. The topic: vertical farming’s role in the circular economy.
The session was moderated by Henry Gordon-Smith, founder and CEO of Agritecture. For those of you unfamiliar with them, Agritecture is an urban agriculture consulting firm. They are based in New York City, but work on projects across the globe (they even gave us advice for our Green Spark project – thanks!).
Each speaker gave a short presentation with some fantastic examples, after which there was a Q&A session. The comments were engaging and critical. Most of the points raised were either about (1) the environmental costs of vertical farming or (2) how urban agriculture is difficult to scale. I agree with this. But to me, the focus on circularity is far more interesting than concerns about vertical farming specifically.
Vertical farming is an amazing technology with plenty of its own advantages and disadvantages – but circular farming and vertical farming are two different and independent things. There were examples of vertical farming in this discussion that had little to do with circularity – and examples of circularity that left out vertical farming entirely.
If these small-scale examples work, I don’t see why they couldn’t be applied in different settings – near the city rather than within it, or in greenhouses rather than plant factories. And that’s only the plant production part of it. Enough of my rambling – let’s get into the participants’ presentations!
Chris Jones – feedingcities.info
Chris has worked on all sorts of landscape design projects all over the world, from Belfast to a rural masterplan in China – but also projects that focus on urban regeneration through applying circular principles. He has now shifted to focus more on food. Loads of different examples came up, but the main focus was the mindset of circular agriculture and how it can help solve problems faced by cities.
It’s about connecting different resources and finding synergies. Look at the local surroundings, figure out what’s being produced as a by-product – there are plenty of opportunities if you look at everything as a resource. There’s a long way to go to achieve full circularity (if that is even possible). The Ellen MacArthur Foundation made this diagram showing the flows of nutrients in cities – only about 2% is looped back!
On a local scale, it’s about analysing the value chain and finding synergies between different industries and forms of agriculture. Within the buildings or production processes themselves, Chris said that efficiency was the main goal. I agree but I’d add that circularity and efficiency can be opposed. For example, feeding livestock corn is more efficient per animal, but feeding them leftover fibres is more circular. Of course, we don’t want to create waste for its own sake and the best waste is that which is never produced – but that’s where we can have an interesting discussion.
Downstream from plant production, there are industries that can make use of by-products, spent materials, biomass, water, plastics (something I’d try avoiding entirely in the first place) and other waste. Within the different forms of plant production, whether indoor or arable, there are opportunities as well: cascading systems, nutrient recycling, biochar and composting, to name a few. Upstream, indoor agriculture can make use of waste heat, CO2 and compost/biochar.
When looking at typical urban and peri-urban areas, two things stand out (apart from its ugliness and lack of walkability): firstly, the low density. There is a lot of wasted space. The second thing that stands out is how all activities are about consumption, as you’d expect. There is no production, which means there are a lot of unused synergies (like the ones mentioned above) between production and consumption. Circularity is also a way to strengthen local economies.
Chris then mentioned how the circular economy is becoming mainstream, with lots of examples: companies like IKEA, urban farms, the use of upcycled and borrowed materials in construction, packaging materials, biogas being used in vehicles…
Alexandre Lefebvre – Alaube
Alex is involved with the be.circular initiative and GoodFood programme in Brussels. This is about making Brussels’s food system more sustainable and providing communal gardens, with the potential of 73 million meals per year. The approach is about finding opportunities like discussed above, keeping it local, and making sure it creates jobs. This is also done with subsidies. Other aspects include resilience, circularity, ecosystem restoration and the reduction of CO2 emissions.
One of the examples Alex mentioned was Le Champignon de Bruxelles, a mushroom grower in Brussels that uses spent grain (which I was fortunate enough to visit its site, the Anderlecht Abattoirs, in 2017). The waste from mushroom production is also used for growing hops at Les Houblons de Bruxelles. Another project, Value Bugs, converts organic waste to chicken feed through black soldier flies. Aquaponics at the FoodMet building was mentioned too – again part of the Abattoir site.
Andrea Rosen – Infarm
Infarm is a company that sells small vertical farms for in supermarkets. As Chris said as well, cities are awkward places to grow food. Infarm makes it easier to get fresh leafy greens by growing them in-store, something technology makes a lot easier. These systems are small-scale, but if you have hundreds of them across a city, the impact it can have is huge. Because production is so local, it is far more traceable as well.
As is the case for vertical farming, it is incredibly efficient when it comes to water and nutrient consumption. Energy, of course, still has a big footprint. Infarm are working on uploading sensor data to the cloud to help optimise production. They are also working on solutions to redistribute waste heat (clever – a supermarket has to be heated after all) and optimise energy consumption based on the grid. Lastly, they are working on using carbon capture technologies to reduce their overall footprint. Sounds like a lot being done!
Peter van Wingerden – Floating Farm
The Floating Farm aims to be a solution to the threat of rising sea levels and supply chain disruptions. It’s a dairy farm in Rotterdam that does in fact float on water, attracting quite some attention. It’s built on a custom concrete-based barge. This was quite an engineering challenge, with corrosive salt water and manure, and a 2-metre tide. Of course their 32 cows produce milk, but the manure is processed into a fertiliser to be used elsewhere. It also uses circular inputs, like grass clippings from the local football stadium and golf courses – to “upgrade waste into protein.”
They are already working on the next ideas: poultry and leafy greens. Happy to see Priva – where I now work – seems to be working with them on this as well.
What stood out was that this project is 100% privately funded, and they expect to break even. And that for the project that seemed the most pie-in-the-sky out of everything here. Circularity wasn’t the initial goal either – shortening production chains was, but circularity ended up being a good way to do that.
Hope you learned something from this article – I certainly did from the webinar. It’s interesting to see GreenTech focus more on circularity, especially since that inevitably means involving more production systems than plants. It could well become AquaFarm on steroids in a few years, who knows. Thanks to everyone on this fantastic webinar – and all the best for 2021!