ORIGINAL RESEARCH article
Front. Environ. Sci.
Sec. Environmental Systems Engineering
This article is part of the Research TopicUrban Hydrology and Hydraulics: Nature-Based Solutions for Pollution and Water ManagementView all articles
Decentralized Rooftop and Container Agriculture Using Greywater and Fog Harvesting: A Feasible Strategy for Water–Food–Energy Security in Mediterranean Urban Environments
Provisionally accepted- Universita della Calabria, Arcavacata di Rende, Italy
Select one of your emails
You have multiple emails registered with Frontiers:
Notify me on publication
Please enter your email address:
If you already have an account, please login
You don't have a Frontiers account ? You can register here
Achieving the Sustainable Development Goals in urban environments, such as zero hunger and agriculture and food security, requires strategies that increase food and biofuel production without adding extra pressure on urban freshwater resources. This study aims to evaluate the feasibility of rooftop and container agriculture in Mediterranean urban environments using two alternative water sources, including domestic greywater and atmospheric fog harvesting. Maize and sunflower are studied as strategic multipurpose crops due to their suitability for selected systems, adaptability to urban microclimates, and double applications in food and biofuel production. The analysis includes an assessment of urban cultivation areas, fog harvesting potential, greywater quality, and selected crop water requirements, besides the importance of simultaneous consideration of food and energy security. Moreover, the detection methods for suitable areas, the potential rooftop and garden agriculture in some case studies, and the feasibility analysis of urban farming in rooftop and container agriculture using fog and greywater has been explored. Results indicate that domestic greywater, produced continuously within households, can satisfy the full irrigation demand for both crops across the entire growing season, while fog harvesting can supply a maximum value of 28% for sunflowers and 34% for maize water requirements. Moreover, the analysis determined that fog water is suitable for direct irrigation, whereas greywater may be used directly for biofuel-oriented agriculture or applied to food crops following a pre-treatment. In conclusion, the investigation demonstrates that combining fog harvesting with greywater reuse provides a practical and decentralized approach to support urban agriculture for multipurpose crops, enhance local food and energy resilience, and reduce dependence on potable-water networks.
Keywords: Biofuels, Climate Change, Energy Security, Fog harvesting, Food security, grain
Received: 14 Oct 2025; Accepted: 23 Jan 2026.
Copyright: © 2026 Pirouz, Anna Palermo, Javadi Nejad, Piro and Turco. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Behrouz Pirouz
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.