Sustainable freshwater from the tropical oceans

The northeast region of Brazil has gone through severe droughts for many decades, which tend to get worse due to the climate change scenarios in the twenty-first century. The population has been migrating southbound, which has brought about serious social imbalances. For the tropical surface ocean waters being the largest thermal solar collectors and reservoirs in the planet, a solution is proposed for inexhaustible supply of freshwater by combining two renewable energy routes through a hybrid offshore energy farm, ocean thermal energy conversion, and offshore wind power. Preliminary feasibility studies are carried out for such an energy farm to deliver freshwater, and to be deployed along the coastline of the northeast region of Brazil. It is calculated 0.43 USD/m 3 as a minimum levelized cost of freshwater, for which the total investments, excluded the desalination units, the freshwater pipelines and the electrical cables, amount to USD 28 billion. Other less capital intensive scenarios are shown, with USD 16 billion investment for 0.57 USD/m 3 levelized cost of freshwater.