By Brent Heard, BS candidate in Economics and Environmental Policy at Carnegie Mellon University and a consultant for the National Academy of Sciences
This post originally appeared on Sense & Sustainability.
As the world population continues to grow, a potential crises is brewing. Food provision has become what more and more people consider an impending crises. The Research Program on Climate Change, Agriculture and Food Security documents that we must feed 230,000 additional people every day in the midst of a changing climate that threatens agricultural productivity. In an article in Time Magazine, Tara Kelly quoted Julian Cribb’s book on the subject, The Coming Famine: The Global Food Crisis and What We Can Do to Avoid It (2011), where Cribb noted, “the world has ignored the ominous constellation of factors that now make feeding humanity sustainably our most pressing task – even in times of economic and climatic crisis.” The need to adapt and improve our agricultural system is evident, and the use of new technologies such as vertical farming may be one part of an effective solution.
As Columbia University professor Dickson D. Despommier identified in a New York Times editorial, climate-change induced floods and droughts are creating disruptions in agricultural practices, resulting in millions of dollars in lost crops. This phenomenon coupled with population increases, the limited nature of land, the water-intensity of farming, and environmental factors such as agricultural runoff creates the need for vertical farms. Despommier’s book, The Vertical Farm (2011), dates the idea of vertical farming back to the hanging gardens of Babylon. Despommier believes that updating this ancient technique with the use of soil-free hydroponic and aeroponic technologies could generate the food crops we need with significantly lower resource consumption.
It has been claimed that vertical farming can be used to grow crops including maize, wheat, and rice in skyscraper-like buildings which can use hydroponic or aeroponic systems to provide a nutrient-containing solution for growth which can be automated for agricultural production. With 80% of the population anticipated to be living in urban areas by 2050, vertical farms provide the advantage of being closer to consumers, as they are likely to be constructed in urban areas, significantly decreasing the transportation required to deliver food from farms to supermarkets. Additionally, these vertical agricultural skyscrapers would operate as a closed system, with crops sheltered from outside diseases or parasites.
The main limiting factor facing vertical farming is the energy required by plants for photosynthesis. The high efficiency and decreasing costs of LED lighting, however, provides potential for vertical farming operations to expand and thrive. As a result, vertical farming companies are beginning to pop up in buildings ranging from industrial warehouses to high-rises everywhere from Pennsylvania to Singapore.
One of Chicago’s start-up vertical farms is taking advantage of LEDs and other technology to improve the cost of producing food and even create jobs in their communities. Green Sense Farms operates by using large stacks of hydroponics systems and combining them with LED growth lighting for plant growth, allowing them to harvest 26 times a year. The Plant, an aquaponic indoor farm, works on a closed-loop system where nearly 27 tons of food waste are consumed by a digester each day, and captures methane and excess heat for farming use as well. These vertical farm start-ups also promise to provide a positive economic impact for the surrounding community, with The Plant alone anticipated to create 125 new jobs when it becomes fully operational.
Sky Greens, a Singapore vertical farming company, employs a novel growing system where plants are rotated on recycled water-powered aluminum frames where plants are exposed to water every eight hours. For dense places like Singapore, vertical farming shows great potential, as real estate is limited and land value is extremely high.
The environmental benefits of vertical farming practices are enormous. The Association for Vertical Farming claims that crops will require an average of 98% less water and 70% less fertilizer, which would significantly decrease the carbon footprint of the food produced. However, vertical farming is not without its share of challenges. Maintenance costs for vertical farms are higher, hydroponic systems require replenishment of nutrients, not all plants can be grown in hydroponic systems, and pollination of crops must be done by hand. Overcoming these challenges will be necessary if vertical farming is to be adapted on a larger scale.
The impending food crisis is serious and it is unlikely that there is a single solution to such a complicated problem. However, vertical farming has the potential to create a large positive impact by providing agricultural crops with fewer environmental costs.