A circular and resource-efficient approach to vegetable growing – in the midst of central Stockholm. It might sound like a fantasy, but this is exactly what Swegreen is doing in the former archives of the Swedish daily newspaper Dagens Nyheter.
– "We want to develop techniques for growing food in urban environments in simpler and smarter ways," says Sepehr Mousavi, chief innovation officer at Swegreen.
Basement level 3 of the Dagens Nyheter building on Kungsholmen, central Stockholm, used to house the newspaper's archives. However, when the archives went digital, the storage space lost its purpose – until a farm for growing organic vegetables moved in. Basil, pak choi, thyme, coriander and other plants grow in dense, vertical rows.
– "This is an example of modern urban agriculture, or urban farming or gardening as it's also known," says Sepehr Mousavi, chief innovation officer at Swegreen, which manages the farm in the former newspaper archives. "It's about growing food in the city in the smartest and most resource-efficient way possible."
Bringing agriculture closer to consumers
The concept brings agriculture closer to consumers, which is not really a new idea, but rather a step towards how food production worked before the industrial revolution. Back then, people grew their food where they lived, but urbanisation changed this, with people working in cities and food grown in the countryside.
– "We're moving food production closer to consumers, but naturally much of the working method has changed," says Sepehr. "Here at Swegreen, we work with small-scale, high-tech agriculture, striving to find the most circular model possible."
Minimising climate footprints
Swegreen's entire business is centred on circularity and resource efficiency, and the pursuit of the smallest possible carbon footprint is apparent. The vegetables are grown vertically to save space. To avoid unnecessary transport into the city, hydroponics is used, which involves replacing soil with substrates made from old PET bottles. And, since the plants are grown deep underground, water-cooled LED lamps are used to provide them with the light they need. The biggest saving, however, is probably measured in terms of water.
– "To grow a kilo of basil in the conventional manner, above ground, you need about 250 litres of water," says Sepehr. "In our circular system, 90 percent of the water is recycled and returned directly to the system. Of the remaining 10 percent, 90 percent is evaporated by the plants in photosynthesis, and by using dehumidifiers we can recover this water as well. So, we use 99% less water than conventional agriculture."
We need carbon dioxide for our plants, and we can get it from the building
Symbiosis between farm and building
The energy used to enable vegetables to grow in a room without daylight also helps the entire building to lower its carbon footprint. By routing the excess heat from the farm's LED lamps back to the building, the need for district heating is replaced by what Swegreen calls "renewable" heat. The farm and the building also interact in other ways.
– "We need carbon dioxide for our plants, and we can get it from the building," says Sepehr. "And, as a thank you, we can give back the oxygen formed when our plants photosynthesise. We could describe this interaction as a kind of urban symbiosis, wherein our systems interact with the building. With the aid of digital solutions, we can take this symbiosis to the next level. We can, for example, see when the building needs energy and when the farm does, and then adapt our actions accordingly."
Collaboration with RISE
Swegreen has collaborated with RISE on the Neighbourfood project since 2019. The aim of the project has been to upgrade an urban farm using modern technology for IoT and AI, which in turn enables further optimisation towards sustainability and the remote control of agricultural processes in what Swegreen calls Farming-as-a-Service – a concept to further contribute to sustainable and peri-urban food production. Charlie Gullström, a senior researcher at RISE, is the project manager of Sharing Cities Stockholm and has spent many years researching smart sustainable cities:
– "Swegreen is an excellent example of the ongoing transition to a circular economy in Swedish cities. There are countless poorly used buildings in our cities that could be used for food production, such as car parks underneath residential buildings. In the sustainable, electrified city, we won't rely on cars for getting around. Local food production will also reduce the need for transport into the city. Urban food production will complement conventional agriculture and comprise part of the development towards positive energy districts in cities by integrating urban farms with the energy systems of the buildings housing them. This is completely in line with the call to action for the transition of our cities currently under way, both in Sweden and within the EU, with initiatives such as Climate Neutral Cities 2030 and the European Green Deal," Charlie concludes.
The Neighbourfood project arose from Sharing Cities Sweden, a national programme that aims to examine how the sharing economy and civic engagement in four Swedish cities can contribute to the climate change transition and which RISE has been a part of since 2017. Neighbourfood is a spinoff from the testbed in Stockholm, which is working together with local stakeholders in the Hammarby Sjöstad district to achieve a local climate goal by changing consumption and transport habits. The project encompasses various initiatives to encourage residents to share services locally and to borrow items from one another rather than buy new ones. With Neighbourfood, the basic idea is to get people in the local neighbourhood involved in food production that can make use of dark places, such as underground car parks. Neighbourfood examines business models and digital technology for running urban farms and distributing vegetables to local residents.