Desalination and Energy: Geospatial approach to energy footprint

Desalination is becoming an increasingly important solution for meeting domestic and irrigation water needs in regions with limited water resources. However, its implementation is associated with increased energy demands. This thesis examines the energy footprint of seawater desalination through reverse osmosis (SWRO) in Greece, focusing on the country’s eight most populous regional urban centers, in order to highlight the variations arising from the geographical and morphological characteristics of each area. The methodology is based on GIS spatial analysis and the use of a Digital Elevation Model (DEM) to generate hydrological derivatives (flow direction and upstream flow length), with the aim of approximating, as realistically as possible, the water conveyance routes (pipelines) from desalination sites to points of demand. The spatial representation of demand is based on WorldPop population data, through which population distribution is estimated at high spatial resolution. At the same time, energy needs are calculated for three key stages: water production through SWRO, pumping to lift water to higher elevations, and energy losses caused by friction during transfer through pipelines. The results indicate that the overall energy burden exhibits significant spatial variations, influenced by transport distances, elevation differences, and daily water demand in each region. The study provides an approximate framework for assessing the energy footprint of desalination, which can serve as a useful tool for the preliminary comparative evaluation of different areas.