How Does Vertical Farming Work?

Vertical farms get their name from the fact that plants are grown on multi-level racks, allowing far greater production per square meter of space. The racks are similar to warehouse shelving units, bearing trays in which the plants are grown. Plants grow either in soil or another medium, or the roots are submerged in water in the case of hydroponics systems.

Modern vertical farms provide light energy for plants using LED lighting. These highly efficient and reliable light sources are installed above the plants, often attached to the underside of the rack above. The light control unit simulates day and night cycles for plants. The most common cycle length is like a nice summer day: 14−16 hours of light and 8−10 hours of darkness. Darkness is crucial, since cellular respiration occurs and other important processes take place at night.

With these lamps the power usage from LEDs accounts for 50 to 65% of the electricity bill. The exact amount depends on several factors: The relative efficiency of the LEDs used, compared with the efficiency of other systems in the farm (such as climate control), as well as the light requirements of each individual crop.

For example, the total electricity required for growing light-loving strawberries in an iFarm, for example, is about 124 kWh per month for each square meter of growing space, while arugula needs only about 76 kWh. There are several ways to reduce energy consumption at vertical farms, learn about in the article "How Much Electricity Does a Vertical Farm Use?"

With it, lighting affects plants' health and weight greatly, and intense light brought plants 23 to 124% more weight compared to basic lighting.

When plants breathe, they turn CO2 into oxygen. Since they can consume much more CO2 than is normally present in air, it’s an engineering challenge to maintain the optimal balance. That’s why vertical farms use a closed-loop ventilation system that includes heating and cooling units, a humidifier and dehumidifier, as well as a CO2 enrichment unit to intensify plant growth. 

High-tech vertical farm equipment providers like iFarm have created innovative solutions to perfect the climate control system. This includes using multiple air conditioning units to circulate the air evenly, and a dehumidification system that recycles excess water from the air for use in watering plants.

Vertical farms use tubes to carry water to the plants automatically, and the water also contains plant nutrition. Nutrient liquids are blended in a precisely-calibrated mixing unit. It’s not enough to get the nutrient mix just right for a given plant. To make sure the plants are "eating well" at all times, the mix is adjusted dynamically using information from sensors. iFarm’s technology calibrates the mix perfectly for each plant at each stage in the growth cycle, delivering it to the correct rack.

In addition to nutrient supply, the water and nutrition system includes storage tanks, pumps, a water quality control unit, and an osmosis filter for removing contaminants, such as minerals, heavy metals, bacteria and viruses. Water is recycled within the system, and comes out of the filtration unit virtually pure.

The nutrition mix in the water isn’t the only aspect of a vertical farm that needs to be continuously monitored and adjusted. In fact, a large vertical farm may be equipped with hundreds of individual sensors, all linked in IoT fashion to a cloud server. The heart of the system is a data processing and control unit, which takes in data from cameras and sensors -- including ones mounted on flying drones!

Plants are very sensitive to their environment, so effective monitoring is key to an efficient vertical farm. Sophisticated systems like iFarm include sensors for EC, CO2, temperature, humidity, web cameras, and others. Even a one-degree deviation from the usual temperature can cause problems and require notification. If the climatic or biochemical limits set by the algorithm are exceeded, technicians are alerted immediately. If they are working remotely, the alerts can be sent through a mobile app.

Of course, the array of sensors and control units need sophisticated software to help them run effectively. Today’s software platforms for vertical farms, such as iFarm’s Growtune, have taken it a step further by using big data to perfect the process. On one hand, the software can analyze what’s happening with the plants in a given farm in real-time, such as their reaction to nutrition. On the other hand, a big set of data from other farms and past harvests is used to perfect the "recipes" or plant-growth algorithms.

Then there’s the business aspect: Growtune software includes managing employee tasks, planning shipments, and calculating expenses and income. This makes a fully enabled vertical farm both efficient in production and cost-effective as a venture.

While employees are still needed, today’s most advanced vertical farms can replace most of the manual labor with automation mechanisms. These include robotic racks that move trays around throughout the growth cycle, such as iFarm StackGrow system, and conveyor systems that can take care of things like seeding, packaging, and cleaning empty trays.

An employee at a high-tech vertical farm is responsible for basic upkeep and maintenance, like replenishing nutrient supplies and replacing worn-out parts. They also need to keep an eye on all the systems listed above, making sure that all the parameters are working as needed. For an idea of how many work hours it takes to run a vertical farm, check out this article.

Luckily, with technology providers like iFarm on the scene, there are experienced tech support experts that can be contacted to help in any situation. And with the ever-growing wealth of data, expertise, and new R&D out there, running these complex systems in your vertical farm is easier than ever. iFarm provides entrepreneurs with ready-to-use farms, with all the hardware and a unique software platform, as well as full service.

21.11.2022