Green Sea Project: An End-to-End Concept Design of an Islanded Solar Desalination Plant and Coastal Reforestation on the North-Western Egyptian Mediterranean Coast

Concept study (white paper, Rev. 00) of an islanded, solar-powered seawater desalination plant on the north-western Egyptian Mediterranean coast (Marsa Matruh – Sidi Barrani), coupled with a monitored coastal green belt. The reference design combines four reverse-osmosis trains of 5,000 m³/d, a 12 MWp tracked bifacial PV field and an 8 MWh battery, delivering on average 10,000 m³/d of fresh water to about 830 ha of planted coast, with no grid connection. The study covers site selection, layout, design basis, beach-well intake, pre-treatment, reverse osmosis, post-treatment, brine fractionation and valorisation, photovoltaics and electrical systems, irrigation hydraulics, nursery and planting, digital twin and control, procurement, construction, quality and standards, commissioning, operations, schedule, budget and risks. It includes 40 plates, a standards register of 130 entries, 13 inspection and test plans, a Class 5 cost estimate and a 15-item risk register. Among the findings of the screening analysis: three trains with an 8 MWh battery fall short of the target; boron tolerance of the planted species drives the sizing of the second RO pass; night-time irrigation pumping costs more energy than it saves; and a 72-hour continuous acceptance test does not suit an islanded plant. Eight innovation modules (brine valorisation, per-plant irrigation, soil chemistry, grafting, flexible desalination, agrivoltaics, carbon accounting, data) are formulated as hypotheses to be tested by pilots, with failures to be recorded in an open register. Limitations: all values are assumptions or screening results. No site survey, vendor data or licensed-engineer calculation has been used, and most standard editions are quoted without verification. The document must not be used for procurement or construction.