Conventional agriculture is one of the largest greenhouse gas emissions sources, accounting for 25% of the total man-made greenhouse gas emissions. Vertical farming is a breath of fresh air for this vital sector, as it can produce a wide variety of crops without having a huge impact on the environment.
Vertical farming can play an essential role in reducing the environmental impact of agriculture. It reduces the amount of water and land required to produce the same or higher amount of food. It also removes the need for long transportation and the use of chemicals and pesticides.
But, despite its positive role in mitigating the devastating effects of agriculture on biodiversity and ecosystems, vertical farming has a dark side as well. Let’s take a closer look at the positive and negative impacts of vertical farming on the environment.
Vertical Farming Factors With Positive Impact on the Environment
Vertical farming has been successful in achieving high production rates while reducing the use of natural resources.
Requires Less Water
Agriculture is the world’s largest freshwater consumer, accounting for 70% to 80% of global freshwater withdrawals. With more than 2 billion people globally affected by water stress, it is more important than ever for agriculture to reduce its water consumption. Vertical farming has managed to reduce water consumption by 95% and, in some cases, by 99%. To put this into context, the production of one kilogram of tomatoes in the fields of Southern Europe requires from 60 to 200 liters of water. To produce the same amount of tomatoes in a vertical farm requires only 2 to 4 liters of water.
So why are vertical farms so efficient in reducing their water usage?
Because vertical farms implement hydroponic and aquaponic systems, the water flows in a closed-loop, so it doesn’t run off from the plants like in the field, and plants can use 100% of it.
Moreover, vertical farms have incorporated dehumidifiers in their systems which collect, purify, and reuse excess water released by plants during the transpiration process.
Requires Less Land
On vertical farms, crops are planted vertically and piled on top of one another, reducing land use, maximizing space, and increasing productivity per unit area.
Because of that, vertical farms have the potential to deal with some of the most pressing challenges posed by conventional agriculture:
- biodiversity loss.
It is estimated that almost 80% of global deforestation is caused by agricultural production, which is also the leading cause of habitat loss. By increasing the number of vertical farms, lands that were once used for farming can regenerate and return to their natural state. Moreover, in the absence of destructive farming techniques, ecosystems and biodiversity will start to flourish again.
Removes the Need For Long Transportation of Produce
Urbanization has increased the demand for food in many urban areas. Nowadays, food travels thousands of kilometers before arriving on store shelves.
In the US, lettuce travels 2,055 miles (3,307 km) to get from farm to fork. When transported over such great distances, foodstuffs use large quantities of fossil fuels and release substantial amounts of carbon dioxide into the atmosphere.
In contrast, vertical farms are typically constructed in abandoned factories or warehouses near urban areas. Vegetables and herbs grown on these farms can reach customers in a couple of hours. Short distances between vertical farms and markets/stores also reduce food loss caused by produce mishandling and spoilage.
For instance, Volcano Veggies, a vertical farm based in the US, says it only takes an hour after harvest for their fresh produce to hit store shelves. Not only does this reduce CO2 emissions from transportation, but it also provides consumers with more nutritious and fresh vegetables.
Don’t Use Pesticides and Preservatives in the Supply Food Chain
In vertical farms, plants are grown in a controlled, closed environment. Because of that, there are not pests; thus, the need for pesticide use is eliminated.
Perishable foods are frequently treated with preservatives and other chemicals before transportation to prevent spoilage. With vertical products, the need for conservation agents is eliminated as these crops are not shipped over long distances and reach the stores within a couple of days.
Eutrophication is a process of enriching the water with minerals such as nitrogen and phosphorous above normal levels. This is partly a natural process, but it is much faster as the fertilizers used by farmers runoff into rivers, lakes, and seas. The derived nitrates and phosphates cause excessive growth of algae, which consume oxygen, so much so that anaerobic zones are formed in the water, in which other species of plants and animals die.
In vertical farming, the risk of eutrophication is virtually non-existent. Plants are grown in a closed system, which doesn’t allow nutrient-rich water to run off into lakes, rivers, and seas.
Vertical Farming Factors With Negative Impact on the Environment
Unfortunately, as with any other agricultural practice, vertical farming also has some adverse environmental effects, which have to be addressed in the future.
Requires a Lot of Equipment
Setting up a well-functioning vertical farm is undoubtedly the most challenging part of the process for many entrepreneurs and farmers. Typically, vertical farms require a lot of equipment to function properly. Some of the most important ones include
- LED lights,
- air humidifiers,
- air dryers,
- air conditioning,
- water purification systems,
- automation systems,
As most of this equipment can only be produced in certain parts of the world, shipping is the only way to access them. During the manufacturing and long-distance transport of these devices, substantial amounts of CO2 and other greenhouse gases are emitted into the atmosphere.
Also, of the equipment mentioned above, only a handful of them (LED lights, sensors, and electronics) can be recycled or reused after the end of their lifecycle. Equipment that breaks down or stops working will likely end up in landfills, contributing to soil and water contamination.
Requires a Lot of Energy
One of the most remarkable differences between traditional and vertical farming is the source of energy. Conventional agriculture utilizes natural energy from the sun to carry out the process of photosynthesis. In contrast, indoor agriculture relies solely on artificial lighting.
It is estimated that a vertical farm of 30 stories requires 10-40 watts of light per square foot on every floor. But the exact amount of energy consumed in a vertical farm depends on the type of cultivated crop.
Vertical farming is also a much more energy-intensive practice when comparing it to greenhouse growing. It is estimated that it takes about 3500 kWh per year for every square meter of growing area to produce lettuce in vertical systems, and only 250 kWh when grown in the greenhouse. About 98% of this energy is used to monitor climate and lighting.
The burning of fossil fuels such as coal, oil, and natural gas to generate electricity is the single largest source of CO2 and other greenhouse gas emissions in the world. As of 2010, they accounted for 25% of the total global emissions. These substantially large amounts of energy required by vertical farming have a huge carbon footprint.
How Can the Negative Impact of Vertical Farming On the Environment Be Eliminated?
Reducing energy consumption is the primary concern of any vertical farm that seeks to mitigate its environmental impact and cut back on its production costs.
Renewable energy provides a long-term and affordable solution to this problem. Solar, wind, and hydropower are excellent sources of clean energy that can help vertical farming reduce its carbon footprint. Renewable energy systems do not produce greenhouse gases, nor do they significantly impact the environment beyond their manufacturing process.
Vertical farms can access renewable energy either directly from their local energy suppliers or by installing solar panels on their rooftops to produce their own clean energy.
More countries are now increasing their renewable energy production, making it easier for vertical farms to switch to clean energy. For instance, Nordic Harvest, a Danish company, joined forces with YesHealth Group from Taiwan to build massive vertical farms powered entirely by wind energy.
Another major concern for vertical farming is the proper disposal of faulty or broken farming equipment. Currently, out-of-service equipment typically ends up in landfill sites, where it poses a serious threat of soil and water contamination. However, introducing a circular economy system between equipment manufacturer companies and vertical farming could solve this problem.
The idea is that manufacturers would lease their equipment to vertical farmers instead of selling it. This way, when a piece of equipment is broken, instead of dumping it in landfills, vertical farms could return it to the manufacturers. Then manufacturers could dismantle and reuse the parts of the returned piece in other production projects.
This circular economy system extends equipment’s life and reduces negative impacts from the deterioration of electronic devices. For this sustainable system to function properly, manufacturers and vertical farms must build a symbiotic and trustworthy relationship.
A similar approach was adopted by Schiphol Airport and its two partners: Phillips and Cofely. Schiphol Airport pays for the light produced as a service, while Phillips and Cofely remain owners of the lamps and their accessories. This symbiotic relationship between Schiphol Airport and its partners Phillips and Cofley ensures that the lamps and their fittings are not thrown away immediately after the first usage.
Only a small number of innovations can transform the global food systems to make them sustainable, and vertical farming is surely one of them. By reducing water and land use and food loss along the supply chain, vertical agriculture promises to play an essential role in helping traditional agriculture reduce its devastating environmental impact.