Agriculture faces the difficult challenge of feeding our ever-growing population, which is predicted to grow to 9.7 billion people by 2050. Yet, land use intensification has led to poorer quality soils that require greater input every year. Meanwhile, sprawling urban areas and industrial developments creep further into rural territory. In fact, it was reported in 2015 that a third of all arable land on Earth has been lost in the past 50 years.
Decades ago, the response may have been to use more fertiliser, pesticides or herbicides to achieve a greater yield. Now, the industry is looking to a more innovative and sustainable solution: vertical farming.
As the need emerges to grow more food in less space, growers are looking upwards. Vertical farming is much more clinical in nature than the name gives away. Facilities are situated indoors, sometimes in heavily populated urban areas, and staffed by scientists wearing lab coats.
It is a much more precise practice than traditional growing methods – all variables are calculated, controlled, and monitored. Temperature, light, humidity, air content, nutrient content and numerous other factors are artificially set to the optimal levels that the plant requires. Plants are grown in layers, that are then stacked on top of each other to make best use of the space.
Soil is a thing of the past, but different companies favour alternative mediums. AeroFarms, in New Jersey, USA, uses a recycled plastic microfleece to deliver nutrients to plants instead of soil. LettUs Grow, based in Bristol, UK, utilises aeroponics, where plant roots are suspended in air that has a constant flow of nutrient-dense mist. Crop One, which started in California, USA, opts for hydroponics, growing crops in a nutrient-dense solution.
The available growing surface in a 1 acre indoor vertical farm can be 4 to 6 times greater than outdoors. Simply put, that means that you can produce more crops in the same physical footprint. Even better, it doesn’t require moving into new arable land, and so preserves biodiversity. Vertical farms can, and have, been set up almost anywhere. Disused office space, abandoned mineshafts, old shipping containers and an underground World War 2 bunker are just some of the unusual locations that vertical farms occupy. This versatility is a great benefit of vertical farming.
Being able to set up shop anywhere is a bonus, but how do the farms perform? Well, vertical farms have been shown to be up to 350 times more productive than their horizontal counterparts. There are various factors that feed into this staggering statistic.
Vertical farming is driven by data. Data is constantly collected on all aspects of the plants’ wellbeing, and scientists use insights to provide the plant with the optimal growing conditions. Some farms even use artificial intelligence and machine learning to predict what the plants need. When everything is so meticulously controlled, the plants have everything they need to grow as quickly as possible, so growers don’t need to rely on chemical fertiliser. This is also the reason that vertical farming uses 70% to 99% less water than traditional agriculture.
Climate change has been of growing concern to farmers who have seen unfavourable weather devastate yields. Vertical farms do not rely on the correct conditions (e.g. temperature, rainfall) to facilitate growth, and crops won’t be affected by adverse weather events like droughts or floods. Being sheltered inside also means that pests are of no concern, so there is no need to use pesticides. These factors lead to an overall greater level of consistency, which means growers can establish long-term supply contracts with retailers without fearing a sudden loss of crops.
Also, vertical farming could reduce reliance on importing foods, reducing emissions from transportation, lowering costs, and providing countries with greater food security. The flexibility to dictate the environment of an indoor farm means that theoretically any crop could be grown anywhere in the world by emulating the conditions of its natural habitat.
Vertical farming seems like it has plenty of benefits to warrant it use, but it comes at a price. 3 to 5 times the price of traditional farming, in fact. One study looked at the viability of growing wheat in vertical structures and found that the yield was several hundred times higher under optimal conditions. However, it was deemed too costly to be economically competitive at this time.
High operational costs are largely down to the high energy consumption, driven by the need for lots of artificial lighting, 24-hour monitoring, and logistics mechanisms such as rotating beds. Initial construction and installation costs are also over twice as expensive as a typical greenhouse. Labour costs are through the roof, as vertical farming requires many highly skilled workers to carry out the delicate work. These workers also must conduct pollination in the absence of natural pollinators, which is a very labour-intensive – and therefore costly – process.
At present, the technology is only suitable for a small range of crops, and most facilities are focusing their efforts on leafy greens. Some experts also worry that plants grown in such artificial conditions will suffer from having poorer nutrient density than those grown in a natural way. However, the technology is still in its infancy, so the industry is sure to address these issues as time goes on.
Vertical farming at this stage in its life cycle appears more like a proof of concept. The yields achieved are undeniably impressive, and this method of growing could greatly lessen our impact on the environment while still being able to feed the world. Certain companies have found massive success in this area, but the scope of what they can grow is still relatively limited. In the future, however, the sky is the limit.
Increased use of robotics and automation could lower running costs of the farms by shrinking the human workforce. There is already some amazing technology on the horizon that allows ‘ag-robots’ to detect flaws in plants, analyse growth rates, as well as handling delicate harvesting tasks. If the industry can overcome some of its early challenges, vertical farming may just be the technological revolution that agriculture has been waiting for.