Living walls have transformed the way we interact with nature indoors, offering a captivating blend of aesthetics and environmental benefits. But with two main approaches – hydroponic and geoponic – the question arises: which method reigns supreme in terms of resource efficiency? This article delves into the resource needs of both systems, focusing on their water consumption, energy efficiency, and maintenance requirements, to guide you toward the most sustainable choice for your design project.
Hydroponic and Geoponic Living Wall Systems
Hydroponic living wall systems embrace a futuristic approach, eliminating soil entirely. Plants are suspended in a unique growing medium with their roots directly exposed to a nutrient-rich water solution.
Geoponic living wall systems, the more traditional approach to living walls, rely on soil as the growing medium.
Water Conservation
Water scarcity is a growing concern globally. Traditional geoponic living walls do not need to constantly circulate water since their soil base allows them to hold onto moisture longer. However, the water in the soil is more prone to evaporation which translates to more significant water usage in order to keep up healthy moisture levels for plants, especially in arid climates.
Conversely, hydroponic systems typically operate on a closed-loop system. Water infused with essential nutrients circulates through the system, reaching plant roots directly. This minimizes water loss through evaporation from the soil surface, leading to dramatic reductions in water consumption. Studies estimate that hydroponics can use up to 90% less water compared to geoponic systems, translating to a significant environmental benefit.
Energy Consumption
While hydroponic living wall systems boast impressive water conservation, questions about their energy consumption often emerge. Unlike geoponic systems, hydroponic living walls rely on pumps to continually circulate water and nutrients, which can increase the energy requirements of the wall. However, a closer look reveals a more nuanced picture. Hydroponic living wall systems, when paired with integrated fans to help circulate the air, can efficiently and effectively improve indoor air quality through a process known as biofiltration. This type of hydroponic system is known as a biofilter living wall. Biofilter living wall systems allow buildings to rely less on constantly bringing in and conditioning outdoor air which translates into lower energy consumption for heating, cooling, and ventilation systems.
All that being said, the data shows that in the long run, a biofilter living wall will actually reduce building ventilation requirements and provide a financial return on the original investment.
Maintenance Matters
Maintenance also plays a significant role in resource efficiency. Geoponic living walls require routine tasks like soil testing, monitoring for nutrient deficiencies, and potential pest control. These tasks tend to be more labour-intensive, requiring frequent visits from service personnel, leading to increased transportation emissions. Conversely, hydroponic systems demand less frequent maintenance due to the more controlled growing environment. Nutrient levels are readily monitored and adjusted, and the risk of pests and diseases is significantly reduced due to the absence of soil. This translates to a smaller environmental footprint associated with maintenance activities.
The Bottom Line
While both hydroponic and geoponic living wall systems offer aesthetic benefits, the evidence leans towards hydroponics when considering resource efficiency. The reduction in water consumption, coupled with the long-term benefits of reduced energy consumption and fewer maintenance visits, creates a compelling case for hydroponics.