Vertical farming breakthrough could save industry from failure

The modern concept of vertical farming was established by Professor Dickson Despommier of Columbia University, in 1999. Since then, it has proven to be deeply polarising, with advocates celebrating its promise of food security, and critics decrying its high energy usage and running costs.

But scientists from the Wageningen University in the Netherlands believe they might just have found the solution.

Could science solve the biggest problem with vertical farming?​

While there are multiple benefits to vertical farming, and we’ll get to those later, there is one major issue, which has plagued it since its inception - high energy usage and, by extension, high costs.

The controlled nature of vertical farming means that the technology it relies upon, providing heat, light and irrigation, must work perfectly for the crops to survive. Natural environmental sources, such as rainwater and sunlight, are not available. This heavy reliance upon technology leaves the industry vulnerable to rising energy costs.

However new research, published in Frontiers in Science, is exploring how dynamic environmental control in indoor farms could help ensure the success of vertical farm crops, while also keeping energy usage and costs to a minimum.

“The biggest benefit of vertical farming systems is that healthy food can be grown much more closely to consumers, in places where this is impossible otherwise - in mega-cities, in deserts, and in places that are cold and dark during large parts of the year,” said Dr Elias Kaiser, first author of the study. “The biggest challenge is the costs associated with electricity use.”

"The biggest benefit of vertical farming systems is that healthy food can be grown much more closely to consumers in places where this is impossible otherwise... The biggest challenge is the costs associated with electricity use.”

Most vertical farm systems are run using constant environmental conditions, which require high levels of energy to maintain. But the scientists’ analysis shows that these demanding conditions are unnecessary.

“We were motivated by the rhythms that plants show on diurnal, as well as on developmental, timescales, which require their growing environment to be adjusted regularly in order to steer their growth perfectly,” said senior author of the study, Professor Leo Marcelis of Wageningen University. “We outline a strategy that makes use of plant physiology knowledge, novel sensing and modelling techniques, and novel varieties specifically bred for vertical farming systems.”

Because plants’ biological functions are heavily influenced by environmental conditions like temperature changes, light wavelengths, and the amount of CO₂ in the atmosphere, manipulating the environment allows a vertical farming system to manipulate plant development. It also allows the farmers to choose when to use higher levels of energy, depending on the time of day and energy price at that time.

“Fluctuations in electricity prices can be used to the advantage of vertical farming systems, by using more electricity when it is cheaper,” explained Professor Marcelis.

The authors created a model for testing smart lighting that aims to keep plants’ ability to photosynthesise steady over the course of a day, while still lowering electricity costs. They found that an optimisation algorithm could cut electricity costs by 12% without compromising a plants’ carbon fixation, just by varying the intensity of the light.

What are the benefits of vertical farming​

Amongst the many benefits of vertical farming, it allows for the optimisation of growth as plants are provided with the ideal amount of water, air, light, soil nutrients and warmth. As well as maximising the chance of crop success, this method offers further benefits, including and utilisation of soilless farming techniques, such as hydroponics​, aquaponics and aeroponics.

“At its simplest, vertical farming means you can grow crops on a smaller footprint, and that’s going to be more important in a world where arable land is increasingly under more pressure. We’re seeing more and more global incidents of extreme weather each year, with crops damaged or destroyed by drought, flooding, unseasonal cold snaps or wildfires​,” said Andrew Lloyd, CEO of vertical farm technology provider, Intelligent Growth Solutions (IGS).

Further benefits include the opportunity to maximise resources, recycling up to 95% of water and operating on a closed-loop system to ensure no surface run off, through its production process. The scope for crop variety is also a huge benefit of vertical farming with over 250 crops currently grown within an IGS vertical farm.

Modular vertical farms can be built up to 12 metres high, while occupying a footprint of just 41m²​​. In contrast to traditional horizontal farming methods, vertical farms do not require high-quality arable land to thrive, and so can be built in urban or brownfield environments, allowing produce to be grown closer to consumers. In addition to maximising land use, this helps to minimise the food miles and carbon footprint of the crops grown and reducing food waste.

Source: Vertical farming goes dynamic: optimizing resource use efficiency, product quality, and energy costs
Published online: 24 September 2024
DOI: 10.3389/fsci.2024.1411259
Authors: Elias Kaiser, Paul Kusuma, Silvere Vialet-Chabrand