Spatial Analysis of Desalination Energy Demand in Greece: Feasibility Zones from the Coastline for Water-Energy Planning

Greece, as a predominantly coastal country, faces increasing pressure on freshwater resources due to climate variability, population distribution, tourism, and agricultural demands. Desalination represents a viable adaptation strategy, yet its energy intensity—particularly for reverse osmosis and water conveyance—varies significantly with distance from the coastline. This study employs a GIS-based feasibility zone analysis around the Greek coastline at incremental distances (10 m, 50 m, 100 m, 1 km, 10 km, 50 km, and 100 km) to spatially quantify the daily energy requirements for desalination and conveyance, aggregated by population and land use zones. Calculations are based on representative specific energy consumption values for desalination (typically 3–5 kWh/m³) and conveyance (increasing with elevation and distance), combined with population distribution data. Results reveal a strong concentration of energy demand near the coast: within 10 km, approximately 60.21% of total national desalination energy demand is covered, corresponding to 66.25% of the population (≈7.24 million people). By 50 km, this rises to 89.50% of energy demand and 93.00% of the population. Beyond 100 km, only 1.27% of the total energy requirement remains, yet with disproportionately higher per-cubic-meter costs due to conveyance challenges. To contextualize feasibility, daily household and services electricity consumption  is allocated proportionally to population per zone. Desalination energy as a percentage of zonal electricity demand remains moderate near the coast but increases inland, highlighting the trade-offs for full national coverage. These findings support that desalination is energetically and technically most viable within 50 km of the coastline, covering the vast majority of the population with relatively low conveyance losses. Inland regions would benefit more from alternative strategies (e.g., rainwater harvesting, wastewater reuse, or inter-basin transfers). The approach provides a first-order metric for prioritizing desalination infrastructure and informs integrated water-energy nexus planning in Mediterranean coastal countries.