With human populations increasing rapidly (the UN projects an increase of 50% to a peak of 9.22 billion by 2075), the crisis of sufficient resources of potable water will be exacerbated. Humans have used various technologies throughout their history to mimic the natural distillation carried out in the water cycle in converting salty ocean water to freshwater. The technology is highly advanced in regions (mostly populated islands and deserts) where there is not enough freshwater to meet the needs of the population. In addition, over 50 percent of the current U.S. population lives in coastal communities near to the unlimited salt water resources of the oceans; on a global basis, over two thirds of the world’s people live within 400 km of those oceans.
Unfortunately, the high costs of desalination technologies have limited their widespread usage. It seems like a logical goal for human societies to move strongly into the development of cost-effective desalination technologies. By doing so, we should be able to move toward the goal of making sufficient water available for all human populations, even if we have to pipe the freshwater long distances inland to reach landlocked population centers.
In addition, the rising costs and dwindling availability of fossil-fuel-driven energy sources will encourage the use of solar energy capture and other alternative energy sources. In the long run, we might even achieve the ideal synergy of using solar energy to desalinate ocean water – just like the natural water cycle.