Future-proofing hydroponics leveraging the circular economy advantage

As people consider how food security factors into a sustainable future, there is a growing focus on methods of stimulating the circular economy. This economic model centers on keeping products and resources usable for longer through sustainable actions, like recycling or repair. These efforts can strengthen supply chains by allowing manufacturers, consumers and others to become less reliant on newly produced goods. 

Figure 1: Hydroponics is growing, yet sustainability and circularity still needs to be addressed. Source: Unsplash

What is hydroponics?

Hydroponics is a growing method that uses a water-based nutrient solution rather than soil. Although some parts of this technique are resource-intensive, it involves a closed-loop system that allows people to reuse some resources and support the circular economy. Additionally, hydroponics farming occurs in controlled environments, reducing or eliminating the use of conventional pesticides. 

Although many methods exist, some reuse the liquid by recirculating it through pipe-based systems. This approach allows people to minimize their water usage, making it particularly appealing in areas that frequently experience droughts. 

Launching a hydroponic agriculture project at school

One of the most appealing advantages of hydroponic growing is that people can do it without needing the expansive fields typically used in conventional agriculture. To exemplify this benefit, sixth-grade students at an Indiana elementary school are growing food to combat scarcity risk. 

Project participants use a vertical system that holds seeds in trays that then go into a growing tower. The seeds began to germinate in as few as two days, keeping students motivated and excited about hydroponics’ potential. These growing efforts may also reduce the school cafeteria’s consumables cost since the vertical garden’s produce can be used in meals. 

This method supports the circular economy by reducing the amount of transported products needed to meet dining needs. The teacher overseeing the project teaches students how to tell when to harvest the crops, check that the plants receive enough water and ensure proper pH balance. The class adjusts those parameters after each growing cycle. Focusing on continuous improvement should help them find what works best and stick to it more quickly, minimizing waste. 

Since this type of hydroponic agriculture does not require large spaces or an extensive setup, it is also an excellent candidate for urban gardening. People who grow in a space as small as their apartment can strengthen food access through self-sufficiency and shrink their carbon footprint. 

Powering hydroponic agriculture with solar energy

Figure 2: Solar power is being used to help sustain farming practices. Source: Unsplash

Solar panels have substantially contributed to a gradual green energy transition, with most systems at least offering an energy efficiency rating between 11 and 15 percent. The efficiency climbs with each solar technological innovation. However, some solar panels are difficult to recycle, and refurbishment efforts are still relatively rare. These realities mean that most end-of-life solar panels end up in landfills. Fortunately, committed groups and companies are working on potential solutions that align with the circular economy. 

While that progress continues, others are interested in combining hydroponics with solar panels. Colombian researchers capitalized on agrivoltaics, which uses solar panels and agricultural processes on the same land to generate both food and energy. This approach protects the plants from intense sun and shields them from wind, creating more consistent growing conditions. 

The research team went further by combining agrivoltaics with hydroponics, incorporating growing towers into solar panel bases. This approach collects rainwater, reducing the need for externally sourced liquid. Estimates suggest this method could grow eight times more plants per square meter than traditional processes. 

Although those involved primarily designed the system to grow vegetables, they also envision other agricultural applications, such as installing it at a dairy farm to give the facility clean energy. However, the next step is to see how well the prototype withstands the local weather, including heavy rains and high winds. Overall adoption rates should improve if the method can last through several growing seasons, potentially prompting efforts to make the innovation commercially available. 

Repurposing spaces to pursue greener ideals 

Figure 3: Indoor farming and automation transform the agricultural sector. Source: Unsplash

Ongoing progress in agriculture means those working in the industry no longer need to endure its most costly or labor-intensive aspects. For example, some farmers use technologies that provide up to 1-centimeter accuracy for automated equipment positioning. They can also let machines do some of the most strenuous and potentially dangerous tasks. Innovative approaches — such as using drones to apply pesticides only where necessary — often preserve more resources, reducing waste and contamination. 

Industries improve when people apply problem-solving mindsets to common challenges. Many agricultural professionals now realize automation can help them do more with less, increasing their competitiveness. 

Automation has also improved hydroponics, especially in indoor vertical farms with tightly controlled conditions and robotic equipment. Keeping assets usable for longer is a foundational characteristic of the circular economy. German researchers have suggested turning disused buildings into vertical farms, which achieves multiple aims. 

First, it prevents people from spending money to build structures from scratch. Secondly, it presents opportunities to bring hydroponically grown produce closer to those who will consume it. Finally, building owners could generate income from new business models once former ones become less effective. 

The research team’s work centered on Wuppertal, Germany, which has many former department stores. They chose one built in 1912 that authorities hoped to repurpose. The researchers created a 3D model that showed how turning the building into a vertical farm was a viable example of minimally invasive adaptive reuse. This creative application of circular economy principles reinforces the value of future-ready hydroponics. 

Enhancing hydroponics farming methods

Hydroponics can align with the circular economy and reduce unnecessary resource use. Since this growing method offers more flexibility than conventional agricultural models, it allows people to explore the potential of producing food in apartments or buildings that would otherwise get demolished. Many examples show that anyone with enough dedication can create a suitable setup or assist with running an existing one to positively impact their community and the planet. 

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