Expect vertical farming to continue to gain credibility as a reliable food source

Dr. Murat Kacira, director of the Controlled Environment Agriculture Center at the University of Arizona, said the ultimate goal in any type of controlled environment production, including vertical farming, is resource-use efficiency. Photo by Rosemary Brandt, College of Agricultural Life Sciences, Univ. of Ariz.

Vertical farm advancements in technology and plant genetics will lead to resource-use savings and increased profitability.

As more retailers like Kroger, Albertsons and Walmart purchase produce grown by vertical farm operations, this segment of the agriculture industry will continue to gain market share. Walmart has taken its commitment to supporting vertical farming a step further by investing in vertical farming company Plenty Unlimited.

Charles Redfield, chief merchandising officer at Walmart, said his company is focused on investing in innovative food solutions in order to deliver its customers affordable, high-quality, fresh food.

“We believe Plenty is a proven leader in a new era of agriculture, one that offers pesticide-free, peak-flavor produce to shoppers every day of the year,” Redfield said. “This partnership not only accelerates agricultural innovation, but reinforces our commitment to sustainability, by delivering a new category of fresh that is good for people and the planet.”

Some retailers are taking their commitment in vertical farming a step further by investing in the production of fresh produce. Publix Super Markets’ GreenWise market in Lakeland, Fla., has installed a 40-foot container hydroponic farm in its parking lot. The store will produce over 700 heads of lettuce weekly which are sold in the store.

Kroger has installed modular vertical farms manufactured by Infarm in two of its Seattle stores. The systems start with seedlings germinated at Infarm’s nursery and then are transplanted into the stores’ production systems to finish and harvest the crops.

Maintaining consistent growing conditions

One of the biggest advantages of vertical farming over other forms of crop production is a consistent finished product. 

“There is consistency for produce yield and quality with vertical farms because it enables complete control of optimal conditions for crops independent of outdoor climatic conditions,” said Murat Kacira, director of the Controlled Environment Agriculture Center and professor in the Biosystems Engineering Department at the University of Arizona. “Delivering a system that can maintain desired conditions also brings the need for resources including the energy to run the grow lights, HVAC systems or other hardware components to deliver those desired growing conditions. 

“The consistent vertical farm environment delivers consistent yield and quality independent of the outdoor environment. When you transplant something in a vertical farm, you know at the end of a given time period what you are going to get in terms of the yield and quality of that product.”

Murat said greenhouses also provide a controlled environment, but the consistency of that environment is still dependent on outdoor climate conditions.

“There is a certain level of independency from the outdoor that can be achieved in a greenhouse, but there is still the dynamics of the inconsistent outdoor environment. This inconsistency also brings the need for energy and resources to maintain desired optimal indoor growing conditions and to minimize crop seasonality effects for crop yield and quality attributes.”

Maximizing resource-use efficiency

Murat said the ultimate goal in any type of controlled environment production is resource-use efficiency. This can apply to the amount of kilowatt hours of electricity used in production, the amount of water, fertilizer, carbon dioxide and labor needed to achieve a specific crop yield and quality attributes outcome.

“There is a resource demand that must be met,” he said. “For any type of agricultural production system, at the end of the day the comparison will be based on yield and quality attributes vs. what goes into the production. This will be factored into the profitability.”

One of the biggest obstacles or opportunities, depending on how you look at it, is the lack of standardization in the systems being used by vertical farms. 

“There are differences in terms of the technologies used and in the systems that are constructed and being operated,” Murat said. “Hopefully some level of standardization will be incorporated. This will take into consideration commercially-available proven products and best practices in the design of production systems that are suited for unique requirements of the systems and crops. Research and development outcomes will further support the advancement of vertical farming systems contributing to enhanced resource-use efficiency and profitability.”

An example is increasing the fraction of the light that is intercepted by the plants can enhance resource-use efficiency.

“This means delivering the light to the plants in very effective, efficient and economic ways so that the light is not lost to other structural elements including walls, aisles and floors,” Murat said. “Considering how plants grow and changes in the plant architecture may require dynamic rather than fixed light controls. There is an opportunity to manipulate the light to achieve substantial savings as much as 20-50 percent from the current levels of electrical energy being used. This may be accomplished through innovative system designs and enhanced environmental controls.”

Murat said there are several areas where grow light enhancements will be combined with lighting techniques to improve energy-use efficiency.

“There will continue to be improvements in LED efficiency and efficacy, but there will be limits as well,” he said. “These improvements can be combined with system designs including light uniformity, light exposure and penetration to the plant canopy, and potential dynamic controls during the production phase. Also, consider the pricing for the electricity, including off-peak hours, pulsing or modulating the light, alternative energy systems and pricing, along with implementing strategic environmental controls to reduce energy use and costs associated with energy inputs.”

While many of the vertical farm advancements may come in technology, Murat said there is also an opportunity for changes in plant genetics.

“Looking at the genetics may lead to breeding new varieties that are better suited for vertical farm environments,” he said. “We can only do so much with engineering and the physical space. Combining the technology advancements with new genetics will help to capture the optimization leading to resource savings and to ultimately increased profitability.’

Integrating automation and robotics

Murat said automation and robotics will play an increasing integral role in vertical farm operations.

“We are already seeing different levels of automation and robotic applications implemented in vertical farms,” he said. “Automation and robotics will be key with vertical farms in regards to labor requirements. The labor input for vertical farms is in the 20-30 percent range of production costs. These costs can be minimized with automation and robotics integration.

“Robotics are able to do many of the repeated processes performed by human operators from seeding to harvesting to packaging. Robotics can also be implemented for scouting and monitoring the crops. This would include making sure the plants in each vertical farm tier are growing properly. The quality attributes that are observed or accounted for by human labor are going to be robotized in future vertical farm systems.”

Murat also expects to see increased implementation of automation for enhanced resource–conserving environmental control strategies related to cooling, dehumidification and fertigation.

“We are going to see more innovation and implementation around how data is related to the crop to further enhance quality attributes and yield and for resource savings,” he said. “For example, this could relate to how light is delivered to enhance quality attributes. Rather than delivering a specific spectrum all the way from transplant to harvest, there might be specific time intervals or times when it makes more sense to provide a unique wavelength to enhance a quality attribute. There will also be increased applications of artificial intelligence, modeling and sensing towards conserving resources and smarter environmental control applications.” 

Murat said the demand for controlled environment educated and experienced graduates remains high.

“Educational programs will continue to produce the next generation workforce with the skill sets most critical to support that need and help grow the CEA industry,” he said. “We will look at what is practical, what is economical, what really makes sense. How technology integration improves the profitability may be the decision-making point.”

For more: Murat Kacira, University of Arizona, Biosystems Engineering Department; mkacira@ arizona.edu; http://ceac.arizona.edu/.

This article is property of Urban Ag News and was written by David Kuack, a freelance technical writer in Fort Worth, Texas.