Background
World population is expected to exceed 9 Billion by the year 2050. By then, 80% of the population could live in urban environments. This presents serious challenges for global food security and sustainability.
According to the FAO, “food security exists when all people, at all times, have physical,social and economic access to sufficient, safe and nutritious food which meets their dietary needs and food preferences for an active and healthy life”.
The Green Revolution contributed to the development of a number of product innovations that led to an increase in global agricultural production. However, a recent plateau in agricultural yields, together with population increase, is sparking a new wave of neo-Malthusian fears. What’s more, despite its benefits in terms of improving food security, the Green Revolution provoked a series of negative effects in the environment (i.e. deforestation, greenhouse emissions linked to mechanisation, pollution of soils or depletion of aquifers).
In response to the unsustainable consequences of conventional agricultural systems, the UN acknowledged the role of technology in achieving sustainable agriculture. In particular, vertical farming has been acknowledged as a potential sustainable solution to food insecurity in an increasingly populated and urbanised World.
What is Vertical Farming?
Vertical farming is a controlled-environment agriculture practice consisting on the vertical cultivation of crops, usually in a greenhouse, and in the absence of soil. It uses LED lighting, temperature control, water systems and nutrient mixes to maximise yields and reduce the use of pesticides, fungicides and fertilisers to a minimum.
Potential benefits
To understand the benefits that vertical farming could provide to global food security, I will provide a few potential benefits of this technology for each of the pillars (availability, access, utilisation, stability) of food security.
Availability
- Higher yields per square metre as compared to soil-based agriculture.
- Farming in a controlled environment can result in the extension of the growing season and might open the door to growing vegetables in places previously unfit for food production (i.e. extremely arid regions).
Access
- Soil-based vegetables are commonly more affordable than those from soil-less farming. However, vertical farming can support the production of cheaper vegetables and increased incomes for farmers in parts of the World where conventional farming is not able to deliver sufficient yields throughout the year due to climate or soil conditions.
- If implemented at a global scale, local production from vertical farms could act as a price stabiliser to global commodity price variations and create new job opportunities, as well as income diversification, in cities.
- Inertical farms in urban rooftops could make these environments self-sufficient in terms of food production, leading to less leakage of money from the city. This could allow communities to re-invest their money in other industries and increase their overall purchasing power.
Utilisation
- The inclusion of vertical farms within the urban environment can provide a teaching space and promote healthier habits amond citizens.
- Shorter supply chains due to local production of vegetables can reduce spoilage, allow freshness of final produce and therefore better nutritional values.
- Vertical farming can contribute to the production of pesticide and herbicide free crops due to the lack of plant competition and controlled environment growing conditions. Besides, hydroponic systems can reduce the use of fertiliser around a 20%.
Stability
- Water usage in these systems is much more efficient than in conventional agriculture. In aeroponic systems, water savings can go as far as 90% when compared to conventional agriculture.
- Due to the potential of controlled environment agriculture to work as an independent and closed system, there is no contamination of water via infiltration of nutrients (i.e. nitrogen and phosphorus) into natural water flows.
- Greenhouse emissions could be reduced as a result of reduced transport requirement, less soil carbon release from farm management, packaging requirements and production of farm inputs
- Also, vertical farming systems can protect crops from floods, droughts and sun. We could therefore consider it as a climate adaptation technology.
Context appears as a key factor in the implementation of vertical farming systems. Setting up vertical farms in cities can provide fresher produce and reduced greenhouse emissions in an increasingly populated and urbanised World. On the other hand, by using controlled-environment technologies, rural areas where climatic conditions are not favourable for conventional farming, can benefits from affordable produce and improved nutritional levels. Therefore, in different contexts, different pillars of food security will be more benefited than others.
Challenges of vertical farming technologies
In spite of the potential benefits discussed above, a number of issues should be considered and adapted to the specific context:
- Energy intensive practice: The reliance of controlled-environment agriculture technology could increase the risk of harvest losses in the event of energy supply failures. A potential solution to this could be the installation of solar panels on farms or the use of urban biproducts to produce energy. Energy-producing infrastructure could help save up money in the long-term, but it would definitely increase start-up costs.
- Potential competition for resources: The intensive of resources (i.e. water, land, nutrients, energy) within cities could create imbalances (i.e. inflation), which could affect the access to food among poorer households negatively. Urban areas are already affected by resource scarcity (i.e. housing crisis in most major cities globally), and the implementation of vertical farming at scale could see this situation exacerbated.
- Crop pollution: Although findings show that urban air pollution would not be an issue in European cities, in cities with a very high concentration of heavy metals in the air, the installation of advance air filters might be necessary, which would add up to the cost of production.
- Limited crop variety: The variety of crops currently grown in these systems lies far behind compared to conventional farming.
- Public opposition: As with GMOs, vertical farming might also face public opposition, and this could slow down its implementation. Involving communities in the management of vertical farms, designing discreet physical structures, using under-utilised buildings to implement farms and stablishing economically independent vertical farms are some of the good-practices that could increase their public acceptance.
- System disruption: Radical change in the food production system would require of the involvement of institutions and capital investors to update regulations on the use of urban resources (i.e. current legislation on listed buildings might stop the implementation of vertical farms in underutilised spaces), and coordinate training needs (vertical farming management requires of a specific set of skills to control temperature, humidity, condensation, irrigation and exposure to light).
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This article used the outputs of some of the work I conducted as student of the MSc in Global Food Security and Development at Nottingham Trent University in 2018-19. For a complete list of the bibliography used to produced this article, please kindly send an email to pablogarciacampos@gmail.com and I will be happy to help.
Image sources: https://2009-2017-fpc.state.gov/252606.htm, https://pixels.com/featured/extreme-housing-in-hong-kong-lars-ruecker.html.
