Abstract

Rapid urbanization, climate variability, and the progressive reduction of arable land are placing increasing pressure on conventional soil-based agriculture. Controlled Environment Agriculture (CEA), particularly hydroponic cultivation systems, has emerged as a promising alternative due to its capacity for precise environmental control, higher land productivity, and improved water-use efficiency. This paper presents a comparative literature review of hydroponic and conventional agricultural systems with a specific focus on land, water, and energy performance metrics. In addition, the role of automation, intelligent control systems, and advanced lighting technologies in enhancing system stability and resource optimization is critically examined. The synthesis of empirical and analytical studies indicates that hydroponic systems consistently outperform conventional farming in terms of land use efficiency and water conservation, particularly in urban and water-scarce regions. However, these advantages are accompanied by significantly higher energy requirements, primarily driven by artificial lighting, climate control, and infrastructure demands. The findings suggest that the sustainability of hydroponic agriculture is highly conditional and dependent on system-level optimization and integration with low-carbon energy sources.

Introduction

Rapid population growth, urbanization, and climate change are placing severe pressure on global food systems. With the global population projected to reach 9.5–10 billion by 2050, food demand is increasing while:

• Arable land is declining

• Rural populations are migrating to cities

• Climate-related disasters (e.g., floods) disrupt agriculture

Conventional soil-based farming depends heavily on land availability, favorable weather, and soil quality, making it increasingly unsustainable in urban and semi-urban regions.

Although alternatives like permaculture and agroforestry promote ecological balance, they require significant land and time, limiting their feasibility in dense cities.

2. Hydroponics as an Alternative

Controlled Environment Agriculture (CEA), particularly hydroponics, has emerged as a promising solution.

Hydroponics:

• Grows plants without soil

• Supplies nutrients directly through water

• Enables precise environmental control

• Reduces resource wastage

• Increases yield per unit area

When integrated with automation technologies (IoT, sensors, AI), hydroponic systems can continuously monitor and regulate:

• pH

• Electrical conductivity (EC)

• Temperature

• Humidity

• Light intensity

• Nutrient concentration

This study provides a theoretical review of automated hydroponic systems and evaluates their sustainability and performance compared to conventional agriculture.

3. Literature Review Insights (2000–2025)

The reviewed research highlights:

• Vertical farming can significantly increase yield per unit area.

• Hydroponics improves water use efficiency (WUE) and reduces land use.

• Energy consumption remains the primary environmental limitation.

• Automation, IoT, AI, and LED technologies improve precision and scalability.

• Sustainability depends strongly on access to low-carbon energy.

4. Overview of Hydroponic Systems

Hydroponic systems grow plants using nutrient-rich water instead of soil. Common types include:

• Nutrient Film Technique (NFT)

• Deep Water Culture (DWC)

• Aeroponics

A typical setup includes:

• Nutrient reservoir

• Water pumps

• Growing channels

• Artificial lighting

• Sensors and control units

Plants rely entirely on controlled parameters such as temperature, humidity, EC, and pH.

5. Comparative Performance Analysis

A. Land Use Efficiency

Hydroponics—especially vertical systems—achieve dramatically higher yields per square meter.

• Yield increases of 150–200% compared to soil-based systems.

• Vertical stacking can increase productivity more than tenfold.

• Enables “zero-acreage farming” (rooftops, building interiors).

However, infrastructure materials and energy inputs may offset land benefits when evaluated through Life Cycle Assessment (LCA).

B. Water Use Efficiency

Hydroponics significantly reduces water consumption through recirculation.

• 70–90% water savings compared to conventional irrigation.

• Tomato production water use can drop from over 100 L/kg to as low as 4 L/kg.

• Average cross-crop water reduction ≈ 85%.

This makes hydroponics particularly suitable for water-scarce regions.

Yet, water savings alone do not guarantee overall environmental superiority.

C. Energy Consumption – The Major Trade-off

Energy demand is the central sustainability challenge.

• Hydroponic lettuce production can require up to 80 times more energy than conventional systems.

• Energy is used for:

  • Artificial lighting

  • Heating and cooling

  • Environmental control

  • Automation

Even urban systems with reduced transport emissions may produce higher greenhouse gas emissions if powered by fossil fuels.

Thus, sustainability depends heavily on:

• Renewable energy integration

• Energy-efficient LEDs

• Optimized climate control systems

6. Role of Automation in Hydroponics

Automation enhances reliability, precision, and scalability.

Automated hydroponic systems use:

Sensors

• pH

• EC

• Temperature

• Humidity

• Light intensity

• Dissolved oxygen

Controllers

• Microcontrollers

• Programmable Logic Controllers (PLC)

• Fuzzy logic systems

• Neural network prediction models

Actuators

• Dosing pumps

• Solenoid valves

• Circulation pumps

• LED grow lights

• Ventilation systems

Closed-loop control systems:

• Continuously monitor conditions

• Automatically adjust parameters

• Reduce human error

• Improve yield consistency

• Enable remote monitoring

Automation is critical for reducing labor and improving system stability.

7. Advantages of Hydroponics

Hydroponics generally outperforms conventional agriculture in:

• Land efficiency

• Water efficiency

• Urban adaptability

• Year-round production

• High-value crop cultivation

It is most suitable in:

• Water-scarce regions

• High land-value urban environments

• Renewable-energy-powered facilities

• High-value horticulture production

8. Challenges and Future Scope

Key Challenges

• High energy consumption

• Infrastructure costs

• Technological complexity

• Economic sensitivity to electricity prices

Research Gaps

• Fragmented studies focusing on isolated components

• Limited long-term operational assessments

• Insufficient integrated life cycle analyses

• Lack of standardized comparison metrics

Future Research Priorities

• Integrated system-level modelling

• Renewable energy integration

• Long-term durability studies

• Economic viability under energy volatility

• Hybrid systems (aquaponics, bioponics)

• Circular nutrient recovery systems

Conclusion

The reviewed literature demonstrates that hydroponic and controlled environment agriculture systems provide substantial improvements in land and water efficiency compared to conventional soil-based farming. However, these gains are offset by increased energy requirements, making sustainability highly dependent on technological optimization and low-carbon energy integration. Hydroponics should thus be framed not as an inherently sustainable agricultural revolution, but as a conditional and context-dependent strategy whose environmental viability emerges only under carefully designed operational and energy frameworks. By solving issues with land scarcity, water use, and climate variability, automated hydroponic systems offer a viable strategy for sustainable urban agriculture. Automation improves system scalability, uniformity, and efficiency, making hydroponics appropriate for both urban and individual food production.

References

[1] Article on “Flood wipe out 30L acres of Hry Crops”. Available: https://timesofindia.indiatimes.com/city/chandigarh/floods-wipe-out-30l-acres-of-hry-crops/articleshow/123929481.cms [2] Land stats: https://fao.org [3] Al-Kodmany, K. (2018). The vertical farm: A review of developments and implications for the vertical city. Buildings, 8(2), 24. https://doi.org/10.3390/buildings8020024 [4] Touliatos, D., Dodd, I. C., & McAinsh, M. (2016). Vertical farming increases lettuce yield per unit area compared to conventional horizontal hydroponics. Food and Energy Security, 5(3), 184–191. https://doi.org/10.1002/fes3.83 [5] Barbosa, G. L., Gadelha, F. D. A., Kublik, N., Proctor, A., Reichelm, L., Weissinger, E., Wohlleb, G. M., & Halden, R. U. (2015). Comparison of land, water, and energy requirements of lettuce grown using hydroponic vs. conventional agricultural methods. International Journal of Environmental Research and Public Health, 12(6), 6879–6891. https://doi.org/10.3390/ijerph120606879 [6] Gruda, N. (2015). Soilless culture system to support water use efficiency and product quality: A review. Agriculture and Agricultural Science Procedia, 3, 283–288. https://doi.org/10.1016/j.aaspro.2015.01.054 [7] Graamans, L., Baeza, E., van den Dobbelsteen, A., Tsafaras, I., & Stanghellini, C. (2017). Can soilless crop production be a sustainable option for soil conservation and future agriculture? Land Use Policy, 69, 102–105. https://doi.org/10.1016/j.landusepol.2017.09.014 [8] Nederhoff, E., & Stanghellini, C. (2010). Water use efficiency of tomatoes in greenhouses and hydroponics. Practical Hydroponics & Greenhouses, November/December, 52–59. [9] Sanyé-Mengual, E., Cerón-Palma, I., Oliver-Solà, J., Rieradevall, J., & Montero, J. I. (2018). Environmental impacts of urban hydroponics in Europe: A case study in Lyon. Procedia CIRP, 69, 540–545. https://doi.org/10.1016/j.procir.2017.11.048 [10] de Sousa, R., et al. (2024). Challenges and solutions for sustainable food systems: The potential of home hydroponics. Sustainability, 16, 817. https://doi.org/10.3390/su16020817 [11] Shamshiri, R. R., Jones, J. W., Thorp, K. R., Ahmad, D., Man, H. C., & Taheri, S. (2018). Advances in greenhouse automation and controlled environment agriculture: A transition to plant factories and urban agriculture. International Journal of Agricultural and Biological Engineering, 11(1), 1–22. https://doi.org/10.25165/j.ijabe.20181101.3210 [12] Gómez, C., & Izzo, L. G. (2018). Increasing efficiency of crop production with LEDs. AIMS Agriculture and Food, 3(2), 135–153. https://doi.org/10.3934/agrfood.2018.2.135 [13] Tatas, K., et al. (2022). Reliable IoT-based monitoring and control of hydroponic systems. Technologies, 10(1), 26. https://doi.org/10.3390/technologies10010026 [14] Luna Maldonado, A. I., et al. (2019). Automation and robotics used in hydroponic system. In Urban Horticulture – Necessity of the Future. IntechOpen. https://doi.org/10.5772/intechopen.90438 [15] van Wee, B., & Banister, D. (2016). How to write a literature review paper? Transport Reviews, 36(2), 278–288. https://doi.org/10.1080/01441647.2015.1065456

Copyright

Copyright © 2026 Dr. Padmini Kaushik, Vedant Ragenwar, Raksha Rathod, Harsha Dongre, Rutika Tikhe, Harsh Nimkar, Lenit Shende, Devang Thakare. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.