In a world increasingly threatened by climate change and environmental stressors, the pursuit of sustainable agricultural solutions has never been more urgent. Vertical farming has emerged as a compelling innovation, promising to revolutionize food production by cultivating crops in stacked, controlled environments that dramatically increase yield and reduce water consumption. However, recent research led by the University of Surrey brings a nuanced perspective to this burgeoning field, uncovering critical challenges that must be addressed before vertical farming can be heralded as a truly sustainable alternative to traditional field-grown crops.
The study, published in the journal Food and Energy Security, offers the first comprehensive lifecycle assessment (LCA) comparing commercially grown vertical farm lettuce in the UK against lettuce cultivated in conventional field farms. Distinctly, this research incorporates soil emissions—an often-overlooked factor in agricultural sustainability assessments—providing a cradle-to-store analysis that spans two UK farms situated on mineral and peat-based soils, and a Spanish farm, which collectively contribute significantly to the UK’s lettuce supply. The study’s meticulous approach offers industry and policymakers a grounded appraisal of vertical farming’s environmental implications and its future potential.
One of the most striking findings of the study is the stark difference in productivity levels between vertical and traditional field farming methods. Vertical farms demonstrated a yield exceeding 20 times that of their field counterparts, producing approximately 97 kilograms of lettuce per square meter compared to the modest 3.3 kilograms per square meter typical of field farms. This leap in productivity is largely attributable to the controlled data-driven environment of vertical farming, where factors such as light, humidity, temperature, and nutrients can be optimized with precision, decoupling crop growth from the vagaries of weather and seasonal cycles.
Equally significant is the drastic reduction in water usage observed in vertical farming systems. Data shows water consumption is nearly eight times lower than that of traditional Spanish farms, which experience considerable irrigation demands due to their hotter and drier climates. Vertical farms utilize only 0.9 cubic meters of water per kilogram of lettuce, compared to a staggering 7.3 cubic meters per kilogram in Spanish land farms. This water efficiency positions vertical farming as a powerful contender in the fight against global water scarcity, especially in regions where agricultural water demand clashes with limited freshwater availability.
Despite these advancements, the study reveals a critical caveat: vertical farming currently incurs a higher carbon footprint than traditional field farming. Even when powered by renewable electricity sources, the greenhouse gas emissions associated with vertically farmed lettuce reach approximately 0.93 kilograms of CO₂-equivalent per kilogram of produce, significantly exceeding the 0.57 kilograms per kilogram associated with typical UK field-grown lettuce. This elevated carbon intensity primarily stems from the substantial energy demands of vertical farming systems, which rely heavily on artificial lighting, climate control, and other mechanical inputs necessary to maintain their controlled environments.
The research team underscores that the predominant contributor to this energy burden lies in the need to simulate optimal growing conditions year-round, requiring consistent electricity consumption for LED lighting arrays and HVAC (heating, ventilation, and air conditioning) infrastructure. These systems are essential to compensate for the limited natural light and to maintain ideal temperatures and humidity levels critical for maximizing plant growth and yield. As such, the environmental cost of electricity production—even when partially sourced from renewables—remains an obstacle to the carbon neutrality aspirations of vertical farming technology.
In addition to energy consumption, the materials used within vertical farms also impact their sustainability profile. The study highlights the role of jute fiber plugs, which serve as soil substitutes to anchor and support plants. Jute is renewable but entails carbon emissions due to its agricultural and processing requirements. Researchers point to promising alternatives, such as coconut coir, a byproduct of coconut processing that offers a similar functional role with significantly lower environmental impact. Transitioning to such materials could slash the land-use footprint of vertical farms by over 95%, illustrating clear pathways toward sustainability optimization in the sector.
Michael Gargaro, the study’s lead author and a postgraduate researcher at the University of Surrey’s Centre for Environment and Sustainability, emphasizes both the promise and current limitations of vertical farming. He states, “Our research shows that while vertical farming technology is capable of boosting productivity and water efficiency dramatically, it still carries a higher carbon cost that must be addressed. The future of sustainable vertical farming hinges on improving energy efficiency and integrating renewables more deeply into these systems so they can truly serve as a climate-resilient food solution.”
Dr. Zoe M Harris, Director of the Centre for Environment and Sustainability and co-author of this important study, reflects on the broader implications for UK food security. The UK currently imports approximately 95% of its lettuce during winter months from Spain, a practice vulnerable to climate-induced droughts and geopolitical disruptions. Vertical farming’s potential to secure a year-round domestic supply not only reduces reliance on imports but also opens opportunities to repurpose agricultural land for restoration projects, such as peatland and woodland conservation, which are critical carbon sinks. However, Dr. Harris stresses that competitiveness requires vertical farms to substantially cut their energy use and reconsider the sustainability of their growth media.
The study’s multi-regional approach adds robustness to the findings, capturing the contrasting environmental contexts of UK mineral soils, carbon-rich peatlands, and Mediterranean agricultural zones. This holistic perspective enables stakeholders to understand not just the technical advantages but also the environmental trade-offs inherent in shifting from field to vertical farming at scale. It highlights the complexity of balancing intensification, resource use, and carbon emissions—a balancing act that will shape the future agricultural landscape in the face of global change.
Importantly, the research extends beyond environmental metrics to touch upon socio-economic considerations. Vertical farming’s ability to provide fresh produce in urban centers while minimizing transportation emissions and spoilage offers a compelling model for resilient, localized food systems. Yet, the higher operational costs linked to energy and infrastructure currently pose challenges for economic scalability, necessitating innovations in technology, policy incentives, and energy sourcing to bridge the gap.
Looking ahead, the study underscores a clear research and development roadmap to make vertical farming a cornerstone of sustainable agriculture. Priorities include enhancing the energy efficiency of lighting and climate control systems through advances in LED technology and smarter automation, increasing reliance on carbon-neutral or carbon-negative energy grids, and innovating in plant growth substrates and packaging materials to reduce environmental footprints comprehensively.
This body of work arrives at a pivotal moment when the global community grapples with interconnected crises of food insecurity, climate change, and dwindling natural resources. Vertical farming represents a tantalizing glimpse into a future where food production transcends traditional land constraints, leveraging technology to feed growing populations sustainably. Yet, as the University of Surrey’s findings make clear, the path to this future demands rigorous scrutiny and sustained innovation to reconcile environmental impact with the urgent need for climate-resilient agriculture.
Ultimately, this study offers a vital reality check: vertical farming can significantly elevate productivity and conserve water but must overcome its carbon challenge to serve as a truly sustainable agricultural paradigm. The UK’s experience may well serve as a blueprint, illuminating both the promise and pitfalls of this breakthrough technology and informing global efforts to forge resilient, sustainable food systems in an era of unprecedented environmental change.
Subject of Research: Lifecycle assessment of vertical farming versus traditional field farming for lettuce production
Article Title: A Comparative LCA of Field Grown Lettuce Versus Vertically Farmed Lettuce
News Publication Date: 21-Aug-2025
Web References:
https://onlinelibrary.wiley.com/doi/epdf/10.1002/fes3.70117
References:
University of Surrey, Food and Energy Security, 2025
Keywords: Sustainable agriculture, vertical farming, food security, greenhouse gas emissions, water efficiency, energy consumption, lifecycle assessment, crop production, environmental policy, climate change, agriculture, resource management
