The number of people on earth is rapidly expanding. It’s been estimated that by 2050, the world’s population will rise to about 10 billion people, of which 80 per cent will live in cities. According to industry experts, based on existing farming practices feeding all these people will require about 20 per cent more land than the country of Brazil. The problem is, over 80 per cent of land suitable for raising crops have already been used up.
Current farming practices do not optimise the use of land or water. Commercial farming also requires extensive use of pesticides. The deficiencies of traditional farming require us to re-examine how food can be better produced for the future. Vertical farming may be a solution.
VERTICAL FARMING
Vertical farming, as its name implies, involves producing food on vertical surfaces instead of one a single level, such as a field or even a greenhouse. The purpose of growing plants vertically instead of horizontally, is to produce more food per square metre.
Since these plants are grown indoors, you cannot rely on natural sunlight for their photosynthesis. Instead, artificial lights are used. In many ways this is better as red and blue LED lights can create the ideal wavelengths for photosynthesis to happen.
There are different mediums used to grow plants in vertical farms but soil is not one of them. Most of the vertical farm concepts out there call for the use of hydroponics although other non-soil mediums like peat moss and coconut husks can be used too. Hydroponics allows for a higher yield as these plants do not need big or long roots to dig deep into the soil to find water and nutrients.
BENEFITS
About 0.4ha of vertical farming is able to produce as much crops as 1.6ha to 2.4ha of conventional farming. Being able to generate higher output from a relative smaller area is the key advantage of vertical farming. However there are many other peripheral plus points as well:
i) Organic produce
Because the plants are grown indoors, within a closed environment, there’s shelter from pests and insects. As such, pesticides and herbicides are not necessary. Vertically-farmed produce are, by their very nature, organic produce.
ii) Less water
In conventional farming, much of the water used is lost in the soil. In vertical farming, much less water is used. It’s been estimated that you can save between 75 per cent and 95 per cent compared to conventional farms because much of the water can be recycled in the system.
iii) Year-round crops
Some produce are seasonal but with vertical farming, which is done in an controlled environment, it’s possible to have year-round crop-production.
iv) Unaffected by weather
Not only does vertical farming negate the effects of seasons, it’s also unaffected by weather conditions outside, whether it’s flash floods or droughts.
LIMITATIONS
The main limitation of vertical farming is that it’s not suitable for every crop that’s grown traditionally. It’s best used for farming leafy green vegetables and herbs. Staple crops like rice, wheat and potatoes are difficult to grow indoors as are tree-based fruits. Still, even with such limitations a lot of produce can be grown to feed the world.
AeroFarms, for example, grows more than 250 types of greens and herbs at its 6,503 sq metres facility in New Jersey. But AeroFarms is unique as it’s really the only major vertical farming facility in the US.
So why hasn’t vertical farming taken off? The main factor is cost. It’s expensive to set up a vertical farm. Constructing a building for vertical farming in an urban setting is costly. Extensive use of technology and sophisticated lighting systems will also use up a lot electricity. The cost of building a 60 hectare vertical farm in a typical American city is estimated at between US$80 to US$100 million (RM320 to RM401 million). This figure would naturally increase if it’s in a big city.
Cost is probably why vertical farming has yet to take off in a big way. A new start-up called Plenty wants to change all that though. It has grand ambitions for vertical farming and is in the process of building a 9,290 square metres vertical farming facility in Washington.
Plenty grows its plants on 6m vertical towers instead of horizontal shelves. These towers are so close together that they look like a wall of plants. Water and nutrients flow down from the top relying on gravity rather than pumps and water is recycled.
Its facilities are very high tech. The plants do not rely on sunlight. Rather LED lamps provide the light they need for photosynthesis. Infrared cameras and sensors are everywhere, collecting data on everything from temperature to moisture to plant growth so that productivity can be optimised.
Plenty plans to build vertical farming facilities and distribution centres near major cities (with more than one million residents) around the world. By having the farming and distribution units close together, just outside the city, they’ll be able to get the produce out to consumers much faster than with conventional farming.
Going by Plenty’s definition of major cities, it’s looking at around 500 of them globally. So far it has raised S$200 million in funding, which isn’t enough, of course, for it to achieve its global ambitions. To do that, it needs to raise more funding and ensure that its crops are commercially viable. If Plenty manages to achieve its ambitious goals, it will go long way towards ensuring that the people of the world decades from now will not go hungry due to the lack of food available to them.
Oon Yeoh is a consultant with experiences in print, online and mobile media. Reach him at oonyeoh@gmail.com