Geospatial Analysis of Energy Requirements for Supplying Desalinated Seawater to the Greek Territory

Abstract

Greece confronts intensifying water scarcity driven by population growth, urbanization, tourism, and climate variability, despite its extensive coastline. Traditional sources are strained, with agriculture consuming ~80% of withdrawals (surface water ~38%, groundwater ~62%). Desalination, predominantly reverse osmosis (RO), offers a mature solution, already meeting 30-95% of domestic needs in Aegean islands, but its energy intensity challenge sustainability within the water-energy-food nexus. This study presents a geospatial framework to assess energy requirements for a hypothetical scenario in which seawater desalination fully supplies domestic water demand in Greece. High-resolution GIS data, WorldPop population grids, and hydrological networks enable estimation of daily demand (173 L/capita/day) and energy decomposition: desalination (SEC = 5 kWh/m³ SWRO), elevation pumping plus residual pressure (15 m head), and frictional losses. The hypothetical pipelines follow reverse natural drainage paths for realistic routing. Results highlight substantial spatial disparities: inland cities face significantly higher and more uniform energy costs (Ioannina: mean dynamic head 8.3 kWh/m³, ~43% higher than the coastal reference of Athens at 5.8 kWh/m³), driven by elevation and distance; coastal centres show lower means but greater variability (Athens: highest total ~3.35 GWh/day). In summary, fully supplying domestic water demand via desalination would necessitate an additional ~8% of the country’s total electricity consumption. Findings affirm desalination’s potential for coastal/island supply while revealing energy barriers inland.

Keywords

Water-energy nexus / Water scarcity / Desalination / Growth / Human progress

Statement of the Use of Generative AI and AI-Assisted Technologies in the Writing Process

The authors declare that Generative AI tools as Grok and ChatGPT were used for helping the translation of the manuscript and the optimization of syntax from the original text.

Author Contributions

Conceptualization, G.-F.S.; Methodology, G.-F.S.; Software, G.-F.S. and I.A.; Validation, G.-F.S., I.A. and M.-A.A.; Formal Analysis, I.A. and M.-A.A.; Investigation, G.-F.S., I.A. and M.-A.A.; Resources, G.-F.S., I.A. and M.-A.A.; Data Curation, I.A. and M.-A.A.; Writing-Original Draft Preparation, G.-F.S., I.A. and M.-A.A.; Writing-Review & Editing, G.-F.S., I.A. and M.-A.A.; Visualization, I.A. and M.-A.A.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The databases utilized are thoroughly outlined and referenced in the citation provided within the text, and they are publicly available.

Funding

This research has received funding from the European Union’s Horizon Europe research and innovation programme under grant agreement No. 101181779 (WATERSENS—Development of Innovative Decentralized Technologies and New Co-Created Governance Models for Water Sensitive Communities). Views and opinions expressed are however those of the author only and do not necessarily reflect those of the European Union. Neither the European Union nor the granting authority can be held responsible for them.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper

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