Engineering efficiencies in vertical farming: a whole-systems approach

IGS technology ensures customers get the most out of every facet in a cost-effective manner, covering everything from energy and fertigation, to spacing and operational use.

This article was guest-written by Dave Scott, Chief Technology Officer and co-founder of IGS. Dave has been at the heart of our product since its inception, bringing a background in industrial automation and electrical control systems to embed and drive efficient practices.

Vertical farming as a concept is built on efficiency. It’s about making more efficient use of land, whether that’s through repurposing brownfield or derelict land, or maximising the growing area of a comparatively small footprint. In designing our technology, we’ve been able to ensure that efficiency is embedded across every facet.  

You can see this across many different areas, from energy usage and how we control the growing environment, through to the way in which the hardware and software that make up our product work in tandem to repeatedly deliver high-quality crops. Best of all, we see it in how our customers put the tech to use in an operational setting, working to create a commercial-scale, profitable agricultural operation.  

Energy efficiency

Modulating airflow through filters and building design

Managing airflow is both one of the most important aspects for maintaining biosecurity in vertical farming, and also in how we manage operational cost efficiency. We do this through high-efficiency particulate air (HEPA) filtration systems and well-insulated modular construction which, when combined, reduce the need to constantly adjust the heating, ventilation and air conditioning (HVAC) to account for external environmental pressures. The construction of our farms bolsters this by ensuring that everything in the building around the towers is tightly sealed (similar in design to other areas you would want to keep as clean as possible, such as a surgical theatre). This makes for a cost-effective solution: the airlock works to maintain clean air, pushing a small volume out and minimising the risk of pests and disease, without putting unnecessary strain on the HVAC.

Optimising lighting

Lighting can account for a significant proportion of spend in vertical farming, so it’s vital we put in place cost-effective systems which maximise its potential. Photon-optimised LED lighting helps here by delivering the precise wavelengths plants require at certain stages of growth – and nothing more – reducing energy consumption. We’re working closely with our crop scientists to refine what that means for each crop at each stage of growth, while also looking at what the desired end result looks like, and how the approach differs based on this. There are so many variables at play here, and it’s an area we’re constantly looking at, but we’re confident that our technology can give the science the platform it needs to drive real efficiencies in crop growth and energy expenditure.

Three-phase power

When designing our vertical farming technology, we were aware of the challenges faced by many large-scale industries when it comes to power usage. All established industrial processes working at scale operate off a three-phase electrical supply – our product is no different. We use all three phases in unison, working to reduce stress on both the grid and the internal system. It natively balances energy across phases, minimising harmonic noise and power loss while maintaining a consistent energy supply. This allows the system to flex and adapt in an efficient manner, delivering the exact lighting that crops need to grow. It’s all about knowing the ins and outs of the problem you’re trying to solve – we've capitalised on this to help make IGS technology the perfect consumer of energy.

Water efficiency

Closed-loop fertigation systems

Electricity usage may be one of the biggest cost factors in vertical farming, but water usage is where some of the biggest gains can be realised. In our closed-loop system, plants receive only the water they need, with measures in place to ensure that any excess doesn’t go to waste. What the plants don’t absorb is collected, filtered, then reused.  

The issue with working with live crops is that you are often left with a slight build-up of salts (undesirable from a site maintenance and cleaning perspective). At our Crop Research Centre near Dundee, Scotland, we’ve put in place a rainwater harvesting system to help manage this. It works to dilute the salts with natural resources (e.g. rain), keeping the water cycle in balance and allowing us to create a circular way of working with nature. Because of this, we can recycle almost 100% of the wastewater from the plants and put it directly back into the system. We encourage customers to put in place similar measures, but where this isn’t possible, the HVAC can step in.

Working with the HVAC to recover moisture

Our technology is designed to extract water from the air through the HVAC and recycle it back into the system. Plants naturally release moisture as they breathe – in a sealed environment this would typically become waste. Our HVAC system captures excess water vapour (like commercial dehumidifiers). All the water we recover then goes back into the system, significantly lessening the overall amount required. When working with a nine-metre IGS Growth Tower, for instance, it can recycle roughly 400 litres every single day. Both of these aspects embed real efficiencies when it comes to water usage.

Space efficiency

We’ve already spoken about how our we space our Growth Trays with Lights to optimise space and the role that our HVAC plays here. This comes back to knowing what the problem is ahead of coming up with a solution – in this instance, the way that heat naturally rises (something that could cause a serious issue when growing vertically). Our HVAC counterbalances this, controlling air pressure across each tray and minimising rise. This works to create consistent microclimates across the towers, maximising the potential of the available growing area.

Another way we optimise space can be seen when looking at the proximity of LED lights to crops. Vertical farming works best when crops are given uniform light distribution from LEDs – this ensures the plant receives the full spectrum needed for optimal growth. The challenge lies in ensuring that plants continue to get a uniform spread of light as they grow closer to the LEDs. Our system is engineered so that it delivers uniform photon delivery, even at close range. It allows crops to grow close to the lights without sacrificing quality, making for more efficient use of space and increasing the growable surface area per square metre of floor space.

Operational efficiency

Low-energy lifts

I'd say that one of the best examples of efficiency in our technology is the lifts that move crops and are used to monitor them. When using lift-mounted cameras to monitor different Growth Trays, the lift uses virtually no energy to move. When descending with a full tray of crops, it actually recaptures energy. This allows our customers to realise cost savings while carrying out important tasks in everyday operations (moving crops and keeping tabs on their growth). They can take this a step further by integrating smart scheduling, maximising efficiency by taking images of crops during watering cycles, for example, reinforcing the lift as a low-impact, yet high-value tool when it comes to operational efficiency.

Integrating AI and ML

I’ve previously spoken about how we use AI and ML in our technology. At the moment, we can use these tools to ensure crops reach optimal height and maintain uniform growth patterns. In time, though, we’d like to see them become more predictive – suggesting changes to lighting, fertigation, or nutritional doses to reach optimal outcomes. There is perhaps even a future where this predictive development becomes autonomous, using closed-loop feedback to evolve recipes in real-time. This would reduce the human interaction required, making use of AI-enabled data modelling to deliver optimal crops.

Whole-farm integration

We’ve always used readily available, commercial off-the-shelf parts when designing our tech solutions. This means that our vertical farms can integrate seamlessly into a wider operation, using existing automation and infrastructure alongside forward-thinking vertical farming technology. As well as the obvious benefits for both supply chain and maintenance, it also creates further operational efficiencies. Growers can integrate vertical farming into their business without experiencing any real pain points, reaping the benefits of known technologies and long-standing supplier relationships.

Efficiency across multiple levels

Efficiency and IGS systems go hand in hand. It's embedded in in the way we power our technology, flexing different phases, maximising the lift to generate new energy, and working in tandem with renewables to make life easier for growers and the hardware they rely on. It’s also rooted in other areas of the product, from complex agronomical areas such as fertigation, through to aspects more clear-cut, such as how it physically manifests and makes use of space. We’re always working closely across IGS to refine this aspect – real efficiencies need to be constantly revised in an ever-changing agricultural landscape. This is what helps to keep our technology ahead of the curve, combining efficient practices with real-world expertise for growers across the world.

Go into more detail on a number of topics within vertical farming and agritech – look at our free-to-download resources.