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Writer's pictureMaria Inês Marreiros

Indoor Farming: The Next Generation Green Revolution?

Between the 1930s and the late 1960s, the Green Revolution prompted new methods and technological advances that increased agricultural productivity worldwide. These included the transition from animal to mechanical power, increased use of chemical fertilizers, synthetic pesticides, and monocropping, i.e. the practice of growing a single crop on the same land year after year. In this era of growing agricultural industrialization, farmers had to become more productive to remain competitive. Small farms that used to grow a variety of crops have given way to enormous farms specialized in large-scale monocultures of single high-yielding crops such as corn, soybeans, or wheat (Khush, 2001). These could produce massive amounts of food more efficiently, and thus assist in feeding the world's growing population. However, this success came at the expense of the environment: an increase in the use of synthetic pesticides, severe soil depletion, and a large carbon footprint (Smith, 1998). In order to feed a population that was expanding and becoming more urban, several farmers and businesses explored for more effective and ecologically friendly methodologies.


Food shortages have plagued mankind since the dawn of civilization. Wars, economic upheaval, climatic extremes and skyrocketing fertilizer prices are all converging to create a food crisis of unprecedented proportions. In 2001, up to 828 million people were unsure where their next meal would come from (Root, 2023). The current global problem of hunger and malnutrition is massive, with an estimated 345.2 million people food insecure - more than double the number in 2020. More than 900,000 people are struggling to survive in starvation-like conditions around the world, a 10-fold increase compared to five years ago (A Global Food Crisis, 2023). Such an alarmingly rapid rise calls for an immediate response. According to current projections, in order to be able to feed everyone by 2050, the global food supply must increase by 70% (Le Mouël & Forslund, 2017). Perhaps more concerning is the fact that it will require 20% more land than is currently needed for cultivation (FAO, 2009). With food consumption increasing even faster than population growth, ensuring global food security, that is, having both physical and economic access to adequate food at all times to meet the nutritional needs for a productive and healthy living, is still a major concern (Sundström et al., 2014). Remarkably, in response to global concerns such as climate change, environmental damage from intensive agriculture, hunger, population growth and urbanization, the food industry is evolving to become more self-sustaining and environmentally friendly. Controlled Environment Agriculture (CEA) has emerged as a solution to massive land-use change and the pressing need to feed the rapidly growing world population (Despommier, 2011; Opitz et al., 2016).

Figure 1 - Over 900,000 people worldwide are battling to survive due to hunger ('Poverty Impacts', n.d.).

Population Boom: The Main Driver of Environmental Degradation

The world population is growing at a rapid pace and is projected to reach 9.7 billion by 2050 (United Nations, 2019), with urban areas accounting for 68% of the total population (United Nations, 2018). This increase in world population is expected to result in a 50% rise in global food consumption, most of which will be disproportionately concentrated in densely populated metropolitan areas. Rapid population growth remains a major driver of environmental degradation and an imminent threat to the sustainable use of natural resources. Competing land-use activities, along with population growth, have shaped a significant portion of the planet's land surface and ultimately led to land depletion and scarcity, whether through deforestation of tropical forests, the practice of subsistence farming, the intensification of agricultural production, or the growth of urban areas (Foley et al., 2005). The end result was ultimately the same: the extraction of natural resources for urgent human needs, often at the price of deteriorating environmental conditions. While humanity has been able to keep pace with population growth by taking advantage of continuous improvements in conventional agricultural processes, the rise of intensive field production is threatened by and contributing to ecological imbalances, crop pests and diseases, water scarcity and diminished quality and quantity of natural resources (Gomiero, 2016, Sundström et al., 2014). This calls into question our capacity to eat sustainably and underscores the importance of rethinking the concept of agriculture as we perceive it today. As the world evolves in ways that challenge the capacity of traditional agricultural systems to meet rising food demands, we must secure our food supply by incorporating cutting-edge and sustainable food production technologies into field agriculture to ensure economic and social benefits while minimizing negative environmental effects (FAO, 2017).


Controlled Environment Agriculture: Fine Tuning Vegetables

There is an increasing recognition that agriculture needs to evolve to use less water and pesticides, make crops less vulnerable to climate change, and provide more consistent yields. Part of the solution may lie in the burgeoning indoor farming industry, where growing conditions can be better managed (EEA, 2017, 2023). Controlled Environment Agriculture, or CEA, is a combination of plant science and environmental control techniques aimed at enhancing the development of plants in confined spaces, often using vertical growth structures (Albright, 1990). CEA, often known as “vertical farming” or “indoor farming”, enables the establishment of fully controlled agricultural growth environments (Autogrow Team, 2020; Controlled Environment Agriculture: What You Need to Know About CEA, 2022). CEA encompasses multiple approaches to food cultivation, including the greenhouse sector, which is currently the main component of the CEA industry, but also the emerging vertical farming segment (Tasgal, 2019). Greenhouses are the more traditional approach, consisting of a single layer of plants grown in an enclosed space with glass or plastic walls and ceilings to allow in natural light, thus providing a semi-controlled setting.

Figure 2 - Chicago is home to the largest rooftop greenhouse in the world. This 2-acre greenhouse, constructed by Gotham Greens, yields the same amount of crops as a 50-acre outdoor farm (Scully, 2019).

Growing on vertical surfaces as opposed to conventional, horizontal farming is what vertical farming means in its purest form (Vertical Farms versus Greenhouses, 2022). Vertical farming involves growing crops in trays that are positioned vertically in layers (or stacks) in a tower-like structure. Such systems are designed to allow plants to grow on top of each other, stretching as far vertically as feasible, offering various advantages, the most important of which is saving space (Masterson, 2022; Vertical Farms vs Greenhouses – The First Consideration, n.d.). In this type of process, traditional agricultural variables such as soil, water, humidity and temperature, oxygen, light and CO2 are replaced with artificial ones (Bailey, 2023). Plants are often cultivated in a water-based nutrient-rich but soilless medium (a growth method referred to as hydroponics) to provide sufficient water and fertilizer to the root zone (Despommier, 2011; Opitz et al., 2016). The latest advancement of organic hydroponics, or "bioponics," streamlines the growing process even further by removing all chemical fertilizers and substituting them with beneficial microorganisms and waste from aquatic animals or plants, that is, natural or organic fertilizers. To offer a surface for the seedlings to attach their roots to, seeds are planted in soil-free growth media, such as coconut shells (Hermann, 2017; Vanacore & Cirillo, 2023). Due to the isolation of these infrastructures from the outside world, solar energy, which is strictly required for photosynthesis (the process by which cells produce glucose and cellulose, the structural material of cell walls), is replaced with LED lighting that is specifically tailored to the energy requirements of the crops. The detrimental effects of variable sunlight are mitigated by supplying the optimal ratio of red, blue, and green light with the appropriate intensity and duration, thereby nurturing growth (Gaal, 2017). Multiple systems continually regulating temperature, humidity, and other variables, as well as LED lights illuminating each layer, assure highly regulated environmental conditions, yet this results in much higher costs when comparing to greenhouse farming.


So, what is it about vertical farming that has propelled CEA to such new heights? While both greenhouses and vertical farming employ hydroponics and are more water-efficient than conventional outdoor agriculture, greenhouses consume substantially more water than vertical farms. Both types of indoor farming allow crops to be grown year-round while using substantially less water and pesticides, as well as the capacity to boost productivity by precisely controlling the quantity of carbon and nutrients provided (Benke & Tomkins, 2017; Van Gerrewey et al., 2021). However, while greenhouses were once more efficient for plant growth, technological improvements such as artificial intelligence and automation have led to significant efficiency gains in vertical farming. Vertical farming has revolutionized the agricultural sector as it increases crop productivity per square meter while also making crop production more uniform and compact (Vertical Farming Pros and Cons, 2022). Vertical farming also allows for less water consumption, removal of pesticides, and more control over quality and quantity. Remarkably, developments in vertical farming technology now allow farmers to forecast harvest quantity and timing (Van Gerrewey et al., 2021; Vertical Farming or Greenhouse Farming?, 2022). Another significant benefit of this approach is the location options for growing vertical farms. Shipping containers, subterranean tunnels, and abandoned mine shafts are unlikely places to grow food. Remarkably, many of these spaces are being transformed into vertical farms.

Figure 3 - Vertical farms, a type of greenhouse that cultivates crops vertically, are currently being operated all over the world (Celen, 2021).

Is the Future of Farming Indoors?

While traditional farmers and the food industry struggle to make fields more productive and farming processes more efficient and environmentally friendly, NASA has been for decades addressing comparable issues for space exploration. Feeding astronauts during long-term space flight demands stretching resources for growing crops in space, such as lowering water and energy usage and eliminating soil, all of which are modern agricultural demands. NASA built the first indoor and vertical farm in the United States in the late 1990s, laying the groundwork for the CEA sector. NASA performed research on plant growth chambers in the Kennedy Space Center's Biomass Production Chamber, which allowed cutting-edge environmental control and monitoring of food crop development (Pierce, 2021; Wheeler, 2020).


To do this, engineers tested a hydroponic system: a collection of devices that make use of vertical space to grow plants in a nutrient-rich water-based solution, typically made from mineral fertilizers, rather than soil. Then artificial lighting, ventilation, and water circulation systems were created. Several crops were planted on the stacked trays to test how well they would thrive (Wheeler, 2020). Particularly noteworthy is that studies conducted in NASA's Biomass Production Chamber have demonstrated that controlled settings may generate food crops with nutrient levels at least comparable to those of field crops (Wheeler, 2017, 2020). The nutritional content of CEA plants has been demonstrated to be even higher in subsequent studies (Mattson, 2023). Later in 1999, the Cornell University CEA program launched the first commercial-scale CEA prototype lettuce production facility in Ithaca, New York. The manufacturing facility was capable of producing 1245 heads of top-quality lettuce daily, marking the transition from CEA research to industrial large-scale production (Mattson, 2023).

Figure 4 - The Biomass Production Chamber, the first controlled environment vertical farm in the United States, assisted NASA in gathering vital information for the indoor farming sector ('How NASA Spinoffs', 2022).

Nordic Harvest, Europe's largest vertical farm, was founded in 2020 and combines renewable energy with robotic technology to recycle water, nutrients and fertilizers. This wind-powered vertical farm near Copenhagen can produce high-quality vegetables without relying on the weather or releasing carbon (Castillo, 2021). By growing and producing more than 200 times as much per square meter as conventional farms, the creative Danish enterprise frees up a greater amount of land for reforestation. The team at Nordic Harvest is currently working to expand the company's capacity for producing vegetables sustainably, from 250 tons annually to 1,000 tons. As they are fully aware that growing only kale, herbs, and lettuce will not transform farming as a whole, Nordic Harvest is constantly developing technology to grow more than just these three crops (Nordic Harvest, 2022).


Another prominent example is the United Arab Emirates (UAE), which imports around 90% of its food due to lack of arable land and water. As a solution, the world's largest vertical farm, Emirates Crop One (ECO 1), was built near Dubai Airport (Peters, 2023). A joint venture between Emirates Flight Catering and Crop One Holdings, ECO 1 first opened its doors last June. While the facility operates on the same principles as other vertical farms, namely using LED light and a precisely tailored combination of nutrients to grow crops without soil or sunlight, the 330,000+ square foot facility is expected to produce three tons of food per day, or more than 2 million pounds of local leafy greens a year while using 95% less water than other crops. The lettuce, arugula, mixed leafy greens and spinach produced by the company are available for passengers flying on Emirates and other airlines. The products sold under the Bustanica name are available for retail sale to UAE citizens (Hall, 2022; Peters, 2023). It is not even necessary to pre-wash the vegetables as they are grown organically without the use of pesticides, herbicides or chemicals.

Figure 5 - Basil and Baby Kale leafs from Nordic Harvest, a wind-powered vertical farm in Denmark ('Nordic Harvest', n.d.).

Conclusion

While global food chains, market competition, industrial processes and increasing productivity have turned agriculture into a profitable economic sector, it is also one of the biggest contributors to environmental and sustainability challenges worldwide. Although indoor farming is not a new concept, vertical farming has ballooned in recent years owing to the fact that it provides a more sustainable method of food production that is emerging as a solution to our diminishing fertile land and significantly increases our ability to produce high-quality and nutrient-rich fruits and vegetables. However, despite these benefits, many still question whether vertical farming is actually scalable. The main challenge for all of these new ventures is to be economically viable at a lower cost compared to traditional outdoor farming. Growth methods that rely on nutrient-based solutions rather than soil and use very little water are currently very expensive. In addition, not all crops are suitable for such a cultivation method. While harvest quality and uniformity can be greatly improved by fully regulating the growing environment with LEDs, sensors and HVAC systems, this makes running vertical farms extremely power hungry and energy consuming. These energy expenditures are a major, if not the major, portion of their operating costs. Additionally, rising energy prices may have hastened vertical farming's demise, but they may also have sparked the development of sustainable business models within the sector to boost profitability, notably through the use of renewable energy. Although high energy costs are anticipated to persist for the foreseeable future, they are also a significant driver for vertical farms to increase their efficiency in a more sustainable manner.

Bibliographical References

A global food crisis. (2023). World Food Programme. https://www.wfp.org/global-hunger-crisis


Albright, L. D. (1990). Environment control for animals and plants. In American Society of Agricultural Engineers.


Autogrow Team. (2020). What is Controlled Environment Agriculture (CEA)? Autogrow. https://blog.autogrow.com/what-is-cea


Bailey, M. (2023). Why Controlled Environment Agriculture (CEA) is the future of farming. Dantherm Group. https://www.danthermgroup.com/en-gb/calorex/why-controlled-environment-agriculture-cea-is-the-future-of-farming


Benke, K., & Tomkins, B. (2017). Future food-production systems: vertical farming and controlled-environment agriculture. Sustainability: Science, Practice and Policy, 13(1), 13–26. https://doi.org/10.1080/15487733.2017.1394054


Briney, A. (2020). History and Overview of the Green Revolution. Thought Co. https://www.thoughtco.com/green-revolution-overview-1434948


Castillo, P. (2021). Carbon-neutral vertical farming: Nordic Harvest. Atlas of the Future. https://atlasofthefuture.org/project/nordic-harvest-vertical-farm/


Controlled Environment Agriculture: What You Need to Know About CEA. (2022). Eden Green. https://www.edengreen.com/blog-collection/what-everyones-saying-about-controlled-environment-agriculture


Despommier, D. (2011). The vertical farm: Controlled environment agriculture carried out in tall buildings would create greater food safety and security for large urban populations. Journal Fur Verbraucherschutz Und Lebensmittelsicherheit, 6(2), 233–236. https://doi.org/10.1007/s00003-010-0654-3


EEA. (2017). Food in a green light: a systems approach to sustainable food. In EEA Report No 16/2017. https://doi.org/10.18356/e2f0ac16-en


EEA. (2023). Rethinking agriculture. EEA. https://doi.org/10.2800/952554


Foley, J. A., DeFries, R., Asner, G. P., Barford, C., Bonan, G., Carpenter, S. R., Chapin, F. S., Coe, M. T., Daily, G. C., Gibbs, H. K., Helkowski, J. H., Holloway, T., Howard, E. A., Kucharik, C. J., Monfreda, C., Patz, J. A., Prentice, I. C., Ramankutty, N., & Snyder, P. K. (2005). Global consequences of land use. Science, 309(5734), 570–574. https://doi.org/10.1126/science.1111772


FAO. (2009). How to Feed the World in 2050. https://www.fao.org/fileadmin/templates/wsfs/docs/expert_paper/How_to_Feed_the_World_in_2050.pdf


FAO. (2017). The future of food and agriculture – Trends and challenges. Rome. https://www.fao.org/3/i6583e/i6583e.pdf


Gaal, T. Van. (2017). Growing Better CEA Crops with Smart Lighting Choices. GreenHouse Product News. https://gpnmag.com/article/growing-better-cea-crops-with-smart-lighting-choices/


Gomiero, T. (2016). Soil Degradation, Land Scarcity and Food Security: Reviewing a Complex Challenge. Sustainability, 8(3), 281. https://doi.org/10.3390/su8030281


Hall, C. (2022). Crop One, Emirate open ‘world’s largest vertical farm’ in Dubai. Tech Crunch. https://techcrunch.com/2022/07/19/crop-one-emirate-worlds-largest-vertical-farm-in-dubai/


Hermann, M. (2017). Bioponics 101. Organic Produce Network. https://www.organicproducenetwork.com/article/62/bioponics-101


Khush, G. S. (2001). Green revolution: the way forward. Nature Reviews Genetics, 2(10), 815–822. https://doi.org/10.1038/35093585


Le Mouël, C., & Forslund, A. (2017). How can we feed the world in 2050? A review of the responses from global scenario studies. European Review of Agricultural Economics, 44(4), 541–591. https://doi.org/10.1093/erae/jbx006


Masterson, V. (2022). Vertical farming – is this the future of agriculture? Climate Champions. https://climatechampions.unfccc.int/vertical-farming-is-this-the-future-of-agriculture/


Mattson, N. (2023). Controlled Environment Agriculture. College of Agriculture and Life Sciences.

Nordic Harvest. (2022). Yes Health Group. https://www.yeshealthgroup.com/partners/nordic-harvest


Opitz, I., Berges, R., Piorr, A., & Krikser, T. (2016). Contributing to food security in urban areas: differences between urban agriculture and peri-urban agriculture in the Global North. Agriculture and Human Values, 33(2), 341–358. https://doi.org/10.1007/s10460-015-9610-2


Peters, A. (2023). Dubai is now home to the largest vertical farm in the world. Fast Company. https://www.fastcompany.com/90769765/dubai-now-has-the-largest-vertical-farm-in-the-world


Pierce, M. (2021). NASA Research Launches a New Generation of Indoor Farming. NASA’s Spinoff Publication.https://www.nasa.gov/directorates/spacetech/spinoff/NASA_Research_Launches_a_New_Generation_of_Indoor_Farming


Root, R. L. (2023). How we got here: The origins of the global food and nutrition crisis. Devex. https://www.devex.com/news/how-we-got-here-the-origins-of-the-global-food-and-nutrition-crisis-105353


Smith, B. D. (1998). The Emergence of Agriculture. In Scientific American Library (1st ed.). W H Freeman & Co. https://doi.org/10.4324/9781003060765


Sundström, J. F., Albihn, A., Boqvist, S., Ljungvall, K., Marstorp, H., Martiin, C., Nyberg, K., Vågsholm, I., Yuen, J., & Magnusson, U. (2014). Future threats to agricultural food production posed by environmental degradation, climate change, and animal and plant diseases - a risk analysis in three economic and climate settings. Food Security, 6(2), 201–215. https://doi.org/10.1007/s12571-014-0331-y


Tasgal, P. (2019). The economics of local vertical & greenhouse farming are getting competitive. AgFunder News. https://agfundernews.com/the-economics-of-local-vertical-and-greenhouse-farming-are-getting-competitive


United Nations. (2018). World Urbanization Prospects 2018. In Department of Economic and Social Affairs. World Population Prospects 2018. https://population.un.org/wup/


United Nations. (2019). World population prospects 2019. In Department of Economic and Social Affairs. World Population Prospects 2019. (Issue 141). http://www.ncbi.nlm.nih.gov/pubmed/12283219


Van Gerrewey, T., Boon, N., & Geelen, D. (2021). Vertical Farming: The Only Way Is Up? Agronomy, 12(1), 2. https://doi.org/10.3390/agronomy12010002


Vanacore, L., & Cirillo, C. (2023). Bioponics: The Next Revolution in Soilless Agriculture. Frontiers for Young Minds. https://doi.org/2023.1009081


Vertical farming or greenhouse farming? (2022). Avisomo Modular Farming. https://avisomo.com/vertical-farming-and-greenhouse-farming/


Vertical farming pros and cons. (2022). iFarm. https://ifarm.fi/blog/2022/11/vertical-farming-pros-and-cons#:~:text=They%20make%20efficient%20use%20of,into%20a%20high%20electric%20bill.


Vertical Farms versus Greenhouses. (2022). iFarm. https://ifarm.fi/wiki/2022/06/vertical-farms-vs-greenhouses-part-4


Vertical farms vs Greenhouses – The first consideration. (n.d.). Agritecture.https://www.agritecture.com/blog/2021/3/4/vertical-farms-vs-greenhouses-the-first-consideration-location


Wheeler, R. M. (2017). Agriculture for Space: People and Places Paving the Way. Open Agriculture, 2(1), 14–32. https://doi.org/10.1515/opag-2017-0002


Wheeler, R. M. (2020). NASA’s Contributions to Vertical Farming. October, 1–22. https://ntrs.nasa.gov/citations/20205008832

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