June 08, 2022 articles
Farming Goes Vertical
Since the first agricultural revolution which occurred some twelve thousand years ago our species has become accustomed to growing their own food and having a consistent, reliable source of nutrition to draw from at any given time. The present global food industry is worth almost nine trillion dollars and makes up ten percent of the world’s total GDP. Its impact is far reaching and of great significance, not only in terms of providing for the health and nutritional needs of the world’s population but also in terms of having a major impact on the planet’s ecology and natural wellbeing.
Approximately 38% of all global land is used for agricultural purposes, one third of which consists of cropland, with the remainder being attributed to meadows and pastures for grazing livestock. A significant figure when you consider that our planet’s population is set to reach nine billion by the year 2050. A question that is arising in and around the agricultural industry at the moment is whether or not conventional farming methods are the best and most efficient way to cultivate food items for the purposes of mass, general consumption. In essence, is there a more sustainable and productive way to service the needs of the industry?
Total Land Area Use by Type and Land Cover
Source: Our World in Data
The above illustration is an image taken from the Our World in Data website which illustrates the different ways that land is used on our planet. The sections are not representative of how land is used in those specific areas of the world, rather they show the quantity of land that is presently used for these designated purposes as represented by total surface area on the planet. Thus livestock takes up almost the entire surface area of North and South America or 27% of total planetary surface area, and includes the area required for grazing land and cropland for animal feed.
Cropland for human consumption takes up roughly the area of China, South Korea, Laos, Japan, and Thailand, amounting to about 7% of the world’s land area. The image illustrates the finite amount of land available to us for use and illustrates how any expansion of livestock or cropland area would likely necessitate further deforestation which, when taking into account global climate change concerns, is simply no longer a viable or sustainable option.
Thus we enter the concept of vertical farming, whose appeal is largely hinged upon the relatively smaller surface area of land required by this method of cultivation. The idea of vertical farming can be traced as far back as the Hanging Gardens of Babylon, however the modern conceptualisation of it was developed in 1999 by Dickson Despommier, a professor of Public and Environmental Health at Columbia University.
A Vertical Farm in Singapore. (Photo attributed to Lionaland Wimons / CC BY-SA 4.0)
In a project aimed at challenging his students to improve crop yield by growing them on the rooftops of New York buildings, he and his students inadvertently stumbled upon indoor farming using artificial lighting in combination with hydroponic and aeroponic growing methods to create abundant crop yields.
Vertical farming projects have since been attempted by various groups around the world attempting to experiment with and explore the possibilities that this approach to crop production can offer. The world’s first pilot production system was installed at Paignton Zoo Environmental Park in the United Kingdom, where the vegetation produced was used to feed the zoo animals. The system was used as a model for exploring the potential of sustainable urban food production and as an educational resource for advocating change in unsustainable land use practices that affect global biodiversity and ecosystem balance.
Commercial projects in countries like Singapore, the United Kingdom and the United States eventually began finding some footing as technologies became more viable and the cost of equipment and technology, LED lighting in particular, dropped substantially thanks to a series of innovative breakthroughs. In 2009, Sky Green Farms in Singapore developed over one hundred, nine metre tall, three story high towers while London based Growing Underground grew leafy produce in underground World War 2 tunnels. The largest commercial vertical farming company presently operating is Bowery Farming in the United States, which has raised about $630 million in funds thus far and is valued at $2,300 million.
Source: Statista
So what do we mean when we use the phrase vertical farming? There are a number of approaches that can be adopted but as the name implies vertical farming essentially involves growing plants indoors in a vertically stacked format while optimising the health and overall production quality of the plants being grown. Vertical farms can be housed within tall buildings, warehouses or repurposed shipping containers, essentially anywhere where the conditions of the environment can be controlled and maintained.
Without getting too technical, hydroponics involves growing plants using coconut husk as a growing medium instead of soil, aquaponics uses fish refuse to provide for the nutritional needs for plants and aeroponics is where plants are suspended and watered without any growing medium. The hydroponic method is the one that is most widely being adopted for the purposes of large scale vertical farming at present.
When we talk about vertical farming, the concept of Controlled-environment Agriculture is one that is central to the use of vertical farming technology at scale. The ability to control the various factors that influence plant growth such as air, temperature, light, water, humidity, carbon dioxide, and plant nutrition are what make vertical farming such an attractive agricultural technology. Because the plants are grown indoors and can be easily monitored, growers are able to augment these factors at every stage of the growth process in order to ensure that the plants are produced to an optimal standard.
An Aquaponics System Using Catfish (Image attributed to Ryan Somma / CC BY-SA 2.0)
Vertical farming offers a range of benefits that make it a viable alternative to conventional farming methods. One of the major advantages involved in vertical farming is that it allows for a greater crop yield per square footage of land. Because of the physical format of vertical farming in which plants are grown upwards in stacked layers this means that more vegetation can be produced with the same amount of floor space as compared to traditional farming methods.
There is then the aforementioned idea of Controlled-environment Agriculture to take into account whereby the various factors that influence plant growth are monitored and adjusted at every stage of the growing process, further allowing plants to be grown at a faster rate than regular outdoor farmed crops. Additionally, vertical farming allows plants to be grown year round instead of being locked into seasonal growth because it is done indoors within controlled environments.
Another major advantage brought about by vertical farming approaches is that the overall quality of the produce is comparatively better than with that of traditional farming. The fruits and vegetables produced are fresher, cleaner and in many cases even tastier than those grown through conventional farming. There are a number of reasons for why this is the case. With hydroponically grown vegetation, the dirt based soil which is usually used for planting is substituted with organic peat soil made from coconut husk. As a growing medium for plants, the coco peat is able to retain more water than regular soil while also being much cleaner due to having antifungal properties.
Vertical farming is also done indoors which means that there is no risk of insects getting to the plants which in turn means that the use of pesticides is entirely unnecessary. Additionally, vertical farms are commonly built in urban areas within cities allowing for produce to be delivered to markets and restaurants in shorter time frames. This removal of long distance delivery has a major impact on the health of the food that ends up on people’s plates. The actual flavour of the food produced can also be affected by changing certain conditions such as lighting levels resulting in a sweeter or crunchier final product.
Source: Vertical Farming Planet
There are also environmental advantages that vertical farming affords. Depending on the type of system that is being used, vertical farming uses up to 95% less water as compared to traditional farming. This is achieved in a number of ways which include strictly controlling the amount of water that goes into the system which can be monitored and regulated via software as well as by collecting and recycling water that evaporates into the air. The previously mentioned coco peat also allows water to be delivered more efficiently as compared to regular dirt based soil. Another environmental advantage of vertical farming is that it uses significantly less land compared to traditional farming, allowing the earth’s natural biodiversity to thrive and remain unaffected.
Although there are many advantages to vertical farming, the technology is not without its own drawbacks. The foremost consideration in this respect would be the cost of building and running a vertical farm which can be substantial. Whether it is due to the power requirements needed by the automated systems used in the farms or the high labour cost of skilled labour required to oversee the growing process, vertical farming can be a heavily costly endeavour requiring upwards of $20 million dollars in up front investment from investors. Operating costs alone, a bulk of which is taken up by electricity demands, can range up to $27 per square foot.
Source: Cambridge HOK
Another disadvantage of vertical farming is that it is highly dependent on technology for its general daily functioning. Besides the financial cost that this incurs, the various forms of lighting, humidity control and automated systems are deeply entrenched in the overall vertical farming system. A power outage lasting a day could therefore significantly impact the profitability of a vertical farm.
Vertical farming is also highly energy dependent as the more efficient and advanced vertical farming systems utilise automation to a high degree. If the vertical farm in question is not powered with some form of renewable energy resource then it can have a significant impact on the environment through the burning of fossil fuels.
We are currently in the age of technologically driven industrial disruption. New technologies are allowing for improvements to be made to many industries, delivering better quality outputs in a more efficient manner. Vertical farming allows for food to be produced faster and to ultimately be both healthier and better tasting. Drawbacks in terms of energy requirements and cost hinder the prospect of scalability but as the technology continues to develop and as more people become aware of the benefits of vertical farming, it could become a highly competitive and viable alternative to traditional growing methods in the years to come.